A great book for experiments, Ενα όμορφο βιβλίο για πειράματα

The Book of Experiments - Leonard de Vries


Το Βιβλίο των Πειραμάτων - Λέοναρ Ντε Βρις

Τρία πανέμορφα παραμύθια

Ο Μικρός Πρίγκιπας - Εξυπερυ


Το Ασχημο Παπάκι - Άντερσεν


Ο Γλάρος Ιωναθαν Λιβινκστον - Μπαχ

Three great fairy tales

The Little Prince - Exupery


The Ugly Ducking - Andersen


Jonathan Livingston Seagull - Bach

It takes time, patience and faith

Reference:


Making Records - Phil Ramone - 1st edition - page 69

Αισθανόμουν μόνος επειδη δεν υπήρχε ένας άνθρωπος να τον θαυμάζω;

Είσαι μια πεταλούδα

Αυτο που κρατάει σε απόσταση ειναι αυτο που φέρνει κοντα

Songs don't always come easy

As smooth as they seem when you hear them in record, great songs don't always come easy. Behind many three or four minute masterpieces are days, months, or years of effort.


Phil Ramone


Reference:


Making Records, the scenes behind the music - Phil Ramone - 1st edition - page 57

Οταν γελάς αστράφτει ο ουρανός

Paul Simon on how he writes songs

"I write from instinct, from an inexplicable sparkle. I don't know why I'm writing what I'm writing. Usually I sit and let my hands wander on my guitar. I sing anything [and I] play anything. When I come across a surprising accident I start to develop it. Once you take a piece of musical information, there are certain implications that it automatically contains: the implication of that phrase elongated, contracted, inverted, or in other time signatures. You start with an impulse and go with what your ear likes."


Reference:


Making Records, Phil Ramone, 1st edition, page 59

Ο σωστός τρόπος να ερωτευτεί κανεις ειναι οπως τα παιδιά

Το γέλιο σου η Ανατολή

Κάθε Συνάντηση Αίνιγμα

Helping people who are aggressive be relieved?

At your own risk.


A good psychotherapist can help get anger away.


In the meantime would giving people the opportunity to destroy something help them be relieved?


For example, sledge hammer, protective helmet, glasses, earplugs and destroying a concrete structure all by oneself. A brick wall?

First a Dream and then it Happens, Πρώτα ενα Ονειρο και μετά η Πραγματικότητα

Valentine - Pink Panther
https://m.youtube.com/watch?v=TfPODQDmsX8

How to reduce ambient noise using omnidirectional mics

The mics must be similar and one is connected out of phase.


We sing to one of them.


An easy way to implement the connection is to connect the mics in series, like Christmas tree bulbs or like resistors, or batteries. But he connection is not (+ -) to (+ -), it is (+ - ) to (- +). So we take XLR  pin 3 of one mic and connect to XLR pin 3 of the other. Then pin 2 of one mic is connected to a new XLR at pin 2. And pin 2 of the other mic is connected to the new XLR at pin 3.


Reference:


Microphones: Design and Application - Lou Burroughs

Electro Voice RE15 and Beyer M55

The RE15 was used with its low cut on. This is an inductor in parallel with the voice coil output, a Pleiades filter.


It sounded amazing at a few inch with a very strong signal output.


Then a Pleiades filter of 160mH, ie 200Hz, was added in line between the mic body XLR out and the female cable XLR.


Now the mic could be used at 1-2in for the same timbre and full spectrum on voice. Of course the signal was even stronger as the mic is much nearer to the source. The signal to noise ratio is phenomenal as all ambience was low cut and only a slight hiss left.


Then the Beyer M55 was connected without any Pleiades filter and used at 0-1in.


The sound was phenomenal and there is something even more dynamic about it. Perhaps more fullness of sound, dynamic and great smooth treble detail. Some ambience could be heard but it sounded nice as it had a natural frequency spectrum. This should not cause a problem as at 0-1in the voice signal is phenomenally strong.


On very noisy situations one can use Lou Burroughs (co-founder of Electro-Voice) trick of
connecting another same omni mic out of phase and singing to one of the mics. It is described in his book Microphones, design and application. An easy way to connect both mics together in series like batteries (a mic is a generator of voltage) is described in the next euroelectron post.


In those tests it must be remembered that the input transformer used has a primary inductance of 400mH which is another Pleiades filter giving a low cut of 70Hz. To find the total cutoff that must be used for correct frequency responce from vocal chords to listener's brain one needs to add all those cut off frequencies to find the resultant cutoff needed.


Then a Pleiades filter or a Pleiades input transformer can be made with the corresponding calculated primary inductance. 200Ω divided by 2 divided by 3.14 divided by the cutoff frequency needed and that equals the inductance needed to be connected across the mic output. The primary turns wanted will turn out to be few. And if a transformer is made it may be of a high step up ratio.


One must also take into account that the particular Beyer used is 500Ω. The RE15 is 200Ω so it can be used with a higher step up transformer ratio to give an even louder signal.


Signal path, setup:


Moving coil directional or omni mic - Pleiades filter (in case of the RE15 in addition to its low cut on) - Canford input transformer with primary inductance of 400mH - Pleiades V4, EF183 operated with 3.4volts - Realistic disco mixer at mic mono input - HD580


(The M55 was connected straight to the Canford input transformer)

Is it possible to make a moving coil microphone with just a few turns of wire

The impedance would be very low and it may be stepped up with a toroidal transformer as on most ribbon microphones.


Would it be then possibly to have a pressure microphone with an extremely thin diaphragm? How is Acoustalloy developed by Electro-Voice made? Can it be read on the Electro-Voice patents.


Pressure moving coil microphones have the reasonant frequency at mid band so that they produce a flat frequency responce by damping it. This seems compatible with a light diaphragm. (Ribbons and directional moving coils need to have the reasonance at low frequency, and condenser at high frequency).


The Magnetec Nanoperm Nanocrystalinne metal glass amorphous tape wound ring cores may do the trick beautifully.


This material is made by almost instantaneously cooling the molten glass. This is done by letting it drop on a large metal rotating barrel. Its large mass opposes changes in temperature and of course it is a very lower temperature compared to the molten glass. So the almost instantaneous cooling creates this unique extreme inductance index property when the material is used as a tape wound core.


One can possibly find a video on Magnetec's website showing how Nanoperm is made.

The best microphone book on the planet?

Microphones: Design and Application - LOU BURROUGHS


Lou Burroughs is the co-founder of Electro-Voice. Awarded 27 electroacoustic patents.


He also wrote the Electro-Voice "Microphone Facts" newsletter.


An example newsletter comparing moving coil microphones to condenser and ribbon ones is:
http://www.electrovoice.com/downloadfile.php?i=971807


An interesting one page account of his life written by John Woram:
http://www.aes.org/aeshc/docs/jaes.obit/JAES_V34_3_PG222.pdf


Some quotes from the first few paragraphs of the book:


The audio engineer and his microphone may be compared to the artist and his paint brush.


Microphone technique is an art and the ear of the listener is the critic.


Lou Burroughs

RCF MD 2702 directional moving coil microphone

There is something nice and easy about the sound of this mic.


It sounds quite loud and there are no s sibilant problems.


The reasonant frequency seems to be higher than other mics and this correctly compensates for the proximity effect for a distance of a few inch.


For very close distance the sound was bassy. A Pleiades filter of 100Hz did not sound quite right (perhaps thin) so one may need to use a Pleiades filter is series with resistance or variable resistor as on MD421?. Is this how the proximity effect is compensated on the MD421? Or a Pleiades filter using a wire that has resistance.


The foam may be disintegrated. The mic can be opened by carefully removing the sticker around. Then 4 metal pins have to be pushed in, in a similar way to MD21 or Beyer M 55.


It can then be opened, the foam removed and the grill washed.


Signal path, setup:


RCF MD 2702 - Canford input transformer (400mH primary inductance) - Pleiades V4 preamplifier, 3.4V battery - Realistic Disco Mixer - HD580

On connecting many Beyer M55 microphones together

An M55 sounds great without the need of EQ or Pleiades filters.


They can be connected to a 3 pole female DIN connector so that no connector modification is needed and the mic stays original.


The fit is quiet tight so that the mics may be (with minimal risk) hung from the ceiling.


The mic length is 2 meters which should be fine for bringing each mic close to the musician.


A vague knot can be made around the mic so that the center of gravity shifts and the hung mic is facing the performer.


The microphone axis can be adjusted by changing the point of contact of the vague knot and the mic body shifting the center of gravity.


So no tripods or stands are needed, and diffraction obstacle effects are minimized.


The mics are virtual shock immune and this applies to their cable too which is now their support.


Slight swinging of the mics is beneficial as it creates a subtle Doppler effect that keeps the brain interested while caressing the basilar membrane by subtle swing of the frequency domain micro variation.


The M55 is balanced.


Each 3 pin female can be soldered to the thin balanced cable that is found inside snake multi cables.


Four of these cables can fit simultaneously inside a Neutrik male XLR.


So 4 microphones can be connected together and have 1 output making a 4 in 1 out without the need of an adding (mixing) console desk.


Inside the Neutrik male XLR the mics can be connected in series for example.


If two 500Ω and two 200Ω Beyer M55 are connected is series the resultant impedance is 1400Ω which seems very suitable to be connected to modern equipment.


Signal will be loud.


Without noise as these mics can be used even at 0in without any change in their pristine sound quality.


The louder instruments can use the 200Ω mics to aid the balancing of sound.


Another four M55 may be connected to a Male Neutrik XLR.


So effectively we now have 8 in to 2 out direct to stereo.


4 mics feed the left Channel and 4 the right channel.


By suitable positioning of mics, panning may be created.


The vocalist can sing in front of 2 mics for being located in the center of the sound image.


The performers will be in a relaxed atmosphere sitting on chairs or standing .


Fairly close together so that they can hear themselves well without the need of headphones.


Each XLR out can be connected to a Pleiades V series one electron tube battery operated pre preamplifier for extremely low noise. This step may not even be needed as the signal is expected loud
and could drive the input stage of a Sony TCD5 pro II tape recorder for example without hiss.


Example signal path:


4 M55 in series -

                           - Sony TCD5 PROII - Sennheiser HD580

4 M55 in series -


This may be possibly the simplest signal path on the planet for recording closed miked sources direct to stereo.


How would it sound like?

3 Great Books, 3 Φανταστικά βιβλία

How to win friends and influence you environment - Dale Carnegie - free PDF
How to stop worrying and start Living - Dale Carnegie - free PDF
Πως ν αποκτάς φίλους και να Επηρεάζετε το περιβάλλον σας - Καρνεγκι
Έξω η Λύπη - Καρνεγκι


Enchiridion - Epictetous
Εγχειριδίον - Επίκτητος


Tao Te Ching - Lao Tsu - PDF
Ταο Τέ Κινγκ - Λαό Τσε

Έχετε τόση λάμψη όση ειναι η λάμψη της ψυχής σας

Η ψυχή σας εχει κατι το αγγελικό

Δεν θαυμάζω μόνο το φυσικό σας ανάστημα αλλα και το ανάστημα της ψυχής σας

Is Joy the prevention for any decease? Ειναι η Χαρά πρόληψη για καθε ασθένεια;

The quality of food, water, air is very important too.


If joy is so important...


Then we must laugh. As it works the other way round too laughter creates joy and happiness.


Another way to be happy is exposing our body to the first and last rays of the sun (taking case not to look at the sun of course). At these parts of the day each photon (packet or quantum of energy) coming from the sun has so much energy that it can penetrate into our body. For some reason this gives happiness too.


Another way is doing what we enjoy.

Ιςως το πιο σημαντικο, The most important?

Ιςως το πιο σημαντικο ειναι αυτο που εμφανίζεται "τυχαία" διπλα μας. οταν δεν έχουμε αλλάξει την πορεία μας για τίποτα.


Που μας δίνει αμέσως χαρά. Μας κανει να γελάμε.


Πρεπει να ειμαςτε ήδη χαρούμενοι για να το δούμε.


Να έχουμε δώσει απλόχερα οτι μπορούμε, γνώση κτλ για να ειμαςτε ανάλαφροι.


Να ειμαςτε ά-φοβοι.


Να μην ζητηθεί τίποτα.


Possibly the most important is what appears by "chance" near us, when we have not changed our course for anything.


That gives us immediate joy. Making us laugh.


We must: already be happy in order to see it.


Have freely given what we can, knowledge etc so that we feel light.


Be fearless (α-φοβοι, a-phob...).


Not ask anything.

One can be very rich with very little money

Μπορεί κανεις να ειναι πολυ πλούσιος με πολυ λίγα χρήματα.

On Saying to a Woman how Beautiful she is

It may have amazing impact if a man tells a woman she is beautiful if this is what he feels.


Εχει πιθανότατα απίστευτη ανταπόκριση οταν ένας άντρας πει σε μια γυναίκα οτι ειναι ομορφη οταν το αισθάνεται.


Μη ζητώντας τίποτα.


Without asking anything.

4 levels we can achieve, 4 επίπεδα που μπορούμε να αποκτήσουμε

These are:


Αντίληψη , Perception


Κατανόηση , Understanding


Αποδοχή , Acceptance
(Reconciliation of facts and reality)


Συνειδητότητα , Consciousness
(Management of previous data)


Example:


You perceive far away someone speaking.


Then you understand he speaks German.


Then you accept the fact that you do not speak German.


Then you try to solve the communication problem.





By Michalis

Copying Helps Learning?

For example copying to a page or computer a part of a classic fairytale by Hans Christian Andersen may do the trick in teaching fairy tale writing.


Same with music, copying for example a score page to blank scoring paper.


J. S. Bach was doing a lot of this. Photocoping machines and scanners were not available at that time.

First Follower Welcome!

Many thanks to all those readers making more than 20 thousand views so far.


Joy comes back.

Total euroelectron views so far is 23753

Canelina the cat, the little electron and photon fairytale

This is a fairytale on how electrons and photos make photovoltaic solar panels operate.


It is written in new Hellenic language on the following euroelectron post.

Η Κανελινα, ο Ηλεκρονιουλης και ο Φωτονιουλης

Η Κανελινα δεν ειναι γάτα σαν τις άλλες.


Τις αρέσει να παιζει με σωλήνες ηλεκτρονίων με τη φίλη της την υπομονετική χελώνα.


Διαισθητικά καταλαβαίνει οτι την ενέργεια για να κινεί τα ηλεκτρόνια την παίρνει απο τον ήλιο αφού φορτίζουν τις μπαταρίες τους με μικρά φωτοβολταϊκά τσέπης.


Δεν καταλαβαίνει όμως πως γινεται και οι άλλες γάτες την κοροϊδεύουν, μην καταλαβαίνοντας και αυτες.


Η Κανελινα δεν το βάζει κατω, βάζει όμως τα κλάματα και σημερα δεν μπορεί να κοιμηθεί πολυ καλα.


Ετςι βραδιάτικα κατεβαίνει στην παραλία στους σοφούς γλάρους να τις εξηγήσουν.


Οι σοφοί γλάροι αποφασίσουν να τις πουν ενα παραμύθι για το πως λειτουργούν τα φωτοβολταϊκά, να της εξηγήσουν και να την νανουρισουν...


Ο Μικρός Ηλεκτρονιουλης


Μια φορά και έναν καιρό ήταν ο Ηλεκτρονιουλης.


Ήταν τοςο μικρός που μπορουςε να βρίσκεται παντού. Μεςα σ' ενα κινητό, στο νερό να κανει με αλλα δισεκατομμύρια δισεκατομμύρια δισεκατομμύρια Ηλεκρονιουλια ενα πλοίο να επιπλέει. Μπορουςε να ειναι στο μυαλό η στο σώμα ενός ανθρώπου. Μπορουςε να ειναι στο μοτέρ ενός ασανσέρ η του τραμ, στα καλώδια του τρόλεϊ, σ' έναν υπολογιστή η ακομα και στο τζαμι ενός αυτοκινήτου.


Η λίστα ήταν ατελείωτη, οι γλάροι συνέχιζαν,..., στα φύλλα των δέντρων, μεςα σ ενα κύτταρο...


Την Κανελινα σχεδόν την είχε πάρει ο ύπνος και ετςι σε τοςο ξεκούραστη διαύγεια μισό ονειρευόταν η μισό άκουγε το παραμύθι...


Ο Ηλεκρονιουλης ήταν απο καλη οικογένεια. Ο παππούς Ηλεκρονιουλης είχε συμμετάσχει στην πρωτη ασύρματη μεταφορά μηνύματος με τηλεγράφημα το 1901, απο Αμερική σε Ευρωπη. Ζούσε στην κεραία απο τη μερια της Ευρώπης. Ήταν ριψοκίνδυνος ο παππούς. Δέχτηκε η κεραία αυτη να κρεμαστεί απο ενα χαρταετό για να φτάσει ψηλά. Ετςι ήθελε ο ηλεκρονικος μηχανικός Γουλιέλμος Μαρκόνι που έκανε το πείραμα αγνοώντας όλους όσους τον κορόιδευαν οτι δεν γινεται. Και ολα αυτα 100 έτη πριν απο την εποχή του internet. Η γιαγιά του Ηλεκτρονιουλη ήταν έξυπνη, ομορφη και γελαςτη Ελληνίδα ποζιτρονιουλα. Ετςι η οικογένεια μετά απο καιρό βρέθηκε στην Αθήνα.


Ειναι νύχτα...


Ειναι τυχερός ο Ηλεκτρονιουλης. Εκεί που βρίσκεται με τα αλλα δισεκατομμύρια, δισεκατομμύρια, δισεκατομμύρια αδέλφια του μπορεί να κοιμάται.


Που κοματια όμως; Αυτο ειναι μυστικό που οι περισσότεροι συνάδελφοι του δεν το γνωρίζουν.


Τα ξαδέρφια του ζούσαν στο μοτέρ του τραμ. Τόσα πολλά μεςα σ ενα τυλιγμένο πηνιο απο μονωμενο σύρμα. Ολα μαζι παρείχαν την δύναμη για να προχωράει το τραμ απο τη Βούλα στο Σύνταγμα. Ειχαν δύσκολη διαδρομή, άσε που το καλοκαιρι ειχαν και ολονύχτιες βάρδιες.


Ποσο τυχερό είμαι, μπορω και κοιμάμαι!


Ξαφνικά βλέπει κατι τόςο μικρο οςο ο ίδιος, που ποτε όμως δεν το εχει ξαναδεί στη γη. Φοράει ενα t-shirt που γράφει photon και εχει ζωγραφισμένο τον ήλιο.


- Μη με πλησιάζεις, ποιο είσαι, απο που έρχεσαι;


- Απο τον ήλιο.


- Πως σε λένε;


- Είμαι ο Φωτονιουλης.


- Εμένα με λένε Ηλεκτρονιουλη. Ειναι μακρυα ο Ήλιος;


- Άστο καλύτερα...


- Ποσο χρόνο κανει να έρθει κάποιος δηλαδή;


- Εξαρτάται απο ποσο γρήγορα τρέχει κανεις. Εγώ είμαι το πιο γρήγορο μάλλον στο σύμπαν!. Κανω 1000 γύρους της γης ώσπου να πεις "φως". Είμαι 1000 εκατομυρια φορες πιο γρήγορο απο μια Ferrari!! Εσυ δεν τρέχεις γρήγορα; Σε βλέπω να στέκεσαι περίπου στο ίδιο σημείο.


- Μπορω να τρέξω πολυ αν θελω. Αλλα κυρίως μ'αρεσει να πηγαινοέρχομαι πχ 1000 εκατομυρια φορες πιο γρήγορα απο ενα παιδάκι σε μια κούνια.


-Αααααααα, εντυπωσιακό, ναι αλλα τι ειναι παιδάκι;


- Καλα πρωτη φορά ερχεται στη γη;


- Θες να πεις οτι μόνο στη γη υπάρχουν παιδιά;


- Μάλλον. (Οι συνάδελφοι του θα έχουν παει σ άλλους πλανήτες που δεν θα εχει εκεί, σκέφτηκε ο Ηλεκτρονιουλης...)


- Άρα είμαι τυχερό.


- Μαλλον. Καμια φορά τα παιδιά ειναι πιο σκανταλιάρικα κι απο μένα.


- Πως μοιάζουν;


- Μοιάζουν λιγο σαν και εμένα. Κανεις δεν ξέρει ακριβως που βρίσκονται. Οι γονεις τους συνέχεια τα ψάχνουν, στο σπίτι, στην πλατεία, οταν παίζουν...Μια μεγάλη διαφορα όμως ειναι οτι εμείς μπορούμε να τα δούμε, αυτα όμως οχι.


- Τι άλλο κοινό έχετε;


- Ζηλεύω οπως κσι αυτα.


- Αλήθεια, ζηλεύεις πολυ;


- Να, βλέπεις αυτη τη κεραία στο βουνό. Ειναι η κεραία ενός ραδιοφωνικού σταθμού. Μεςα της χορεύουν με το ρυθμό της μουσικής τα αδέρφια μου που ξενυχτάνε. Ετςι ζηλεύω και αρχίζω να κουνιέται με τον ίδιο τροπο. Αν τώρα ζούσα σε μια κεραία ραδιοφώνου, χάριν σε εκείνα και σε εμάς τα αλλα ηλεκτρόνια της κεραίας λήψεως θα ερχόταν, η μουσική στο ραδιόφωνο, κάνοντας μικρούς και μεγάλους να διασκεδάζουν χορεύοντας...


Μ'αρεσει οπως μιλάς. Θελεις να γίνουμε φίλοι;


Ναι και θελω να σου ζητήσω μια χαρη.


Τι χαρη; Ακομα δεν γνωριστήκαμε, για πες;


Οι άνθρωποι φτιάχνουν επιτέλους φωτοβολταϊκά σε πιο ευρεία κλίμακα. Βλέπεις θέλουν όλο κσι πιο πολυ ενέργεια. Άσε που μάλλον τελειώνει το πετρέλαιο. Εγώ είμαι μεςα σ'ενα φωτοβολταϊκό με πάμπολλους ακομα ηλεκτρονιουληδες. Οταν βλέπουμε τους συναδέλφους ηλεκτρονιουληδες στον ήλιο να παλλονται απίστευτα γρήγορα, ζηλεύουμε φυσικά και αρχίζουμε να κινούμαστε ετςι και εμείς. Θα προτιμούσα όμως να μην ζηλεύω και απλά να έρχεσαι εσυ να με ξυπνάς μ' ενα απλό σκούντημα. Εχω βαρεθεί να ζηλεύω.


Μα τι έπαθες ονειρεύεσαι; Αυτο το κανουμε ήδη εδώ κσι εκατομυρια έτη! Μήπως οοονειρεύεσαι;


Δεν πρόλαβε να τελειώσει τη φράση του και ο Ηλεκτρονιουλης είχε ήδη ξυπνήσει. Κοιμόταν μεςα σ' ενα φωτοβολταϊκό πανέλο και αισθάνθηκε ενα σκούντημα απο τον Φωτονιουλη να τον ξυπνάει. Είχε ξημερώσει. Και ο φίλος του ο Φωτονιουλης μόλις έφτασε απο τον ήλιο.


- Ξυπνά φίλε μου. Έχεις να προχωρήσεις ανέμελα μεςα σε χάλκινα καλώδια και να πας σε διάφορες ηλεκτρονικές συσκευές που σε περιμένουν για να λειτουργήσουν. Η ν' αποθηκευτεις μαζι με τους άλλους σ' ενα συσσωρευτη (μπαταρία). Θα είσαι εκεί μαζι με δισεκατομμύρια δισεκατομμύρια Ηλεκτρονιουλια έτοιμο να πεταχτεις σαν ελατήριο μόλις κάποιος πατήσει το κουμπί κσι ενωθεί το κύκλωμα.


Ο Ηλεκτρονιουλης σηκώθηκε. Μόλις πρόλαβε να πιει λιγο χυμό κσι να πλύνει με καθαρο θαλαςςινο αλατόνερο τα δόντια του. Ντύθηκε γρήγορα κσι έτοιμος ξεκίνησε το μαγικο ταξίδι του. Και το βράδυ ιςως γίνει χορός!


Η Κανελινα ήδη είχε κοιμηθεί. Ονειρευόταν χαρούμενη οτι όλοι μαζι αρχίζουν να χορευουν στην παραλια μαζι με τον γάτο με την πραςινη κορδελα. Πράγμα που θα συμβεί μόλις ξημερώσει και τα πρώτα υπερμωβ διυσδητικα φωτόνια του Ηλιου ξυπνήσουν τα ηλεκτρόνια της γης, και αυτα βαθειά μεςα στο σώμα και την ψυχή μας. Τα ηλεκτρόνια της χαράς. Και όλοι μαζι θα χορέψουν κατω απο το φως του Ηλιου που δεν αφηνει καμια σκια στην αλήθεια.


Αύριο ξημέρωμα θα έρθουν τα πρώτα φωτόνια πανω στη γη σε κάλεσμα γιορτής.


Πηγες:


Electrons go to Work - J. Gordon Cook


The Feynman Lectures in Physics - Feynman, Leighton, Sands


Το Βιβλιο των Τηλεπικοινωνιων - Λέοναρ Ντε Βρις - Εκδωσεις Λαμπάκη


Public Domain


Δημόσιο κτήμα οπως και οτιδήποτε στο euroelectron που δεν προσβάλει δικαίωμα άλλου.

PA Solutions Shop in Athens

A very nice shop where one can buy Neutrik connectors, pro video, audio cables, for example Sommer, Konig & Meyer stands etc.


Very friendly atmosphere.

Definition of Technology

Technology means doing more with less.


Michalis

Beyerdynamic M 55 LM or K Microphones

The newer black versions have been tested too. The LM is terminated with a 3 pin DIN and the K with a 1/4in. They are 500Ω too.


It is hard to believe how good all the Eugen Beyer M55 microphones (including the older ones) sound.


You would think that you are dreaming.


The M55 HN might have sounded less full and loud but this seems to be because they are 200Ω and they would sing with an input transformer of 1:20 or more rather than the 1:10 or more used on the 500Ω versions.


Setup, signal path:


Male singing at 1 in - Beyerdynamic M55 LM - Canford impedance converter XJ (input transformer with 400mH primary inductance) - Pleiades V4  (the EF183 electron tube 3.4V battery operated) - Realistic disco mixer mono mic in - Sennheiser HD580 precision

Με κανεις να φαίνομαι σχεδόν κανονικός άνθρωπος

Sennheiser MD 441 U3 and Pleiades Filters

This is the MD441 type without the low cut filter.


Various cut off frequencies of Pleiades filter were tried in an attempt to:


1. Use the mic at 0in.


2. Use it for singing a type of song such as the beautiful with beautiful vocal: Going to a Town - George Michael:
https://m.youtube.com/watch?v=8DZJQjn3jV8


Phil Ramone can be seen producing.


(Is the microphone used on this song the SKM 5200 with the Neumann KK 104 condenser capsule?)


Firstly (while singing this song for this experiment) a Beyer M 55 was tried without any Pleiades filter. It sounded very nice but bass heavy. It seems singing voice needs less bandwidth than speech to sound correct to our brain.


Then the MD441 U3 was connected directly and as expected at 0in the sound was eeeeexxxxxxxtremely bass heavy due to the proximity effect. This is good news as when the right Pleiades filter is applied, making the voice sound correct, all background far off noise and ambience will be out. This is a very effective noise canceling principle invented so many years ago.


The 0-1in distance capability is very useful too as you can see George Micahel performing live while recording at the Air Studios Lyndhurst (church) near the full orchestra without wearing headphones, if the master take happened this way.


The cutoff 6dB per octave frequency in the setup used is already 70Hz because of the parallel inductance of the Canford input transformer which has a primary inductance of 400mH.


Then a Pleiades inline XLR filter of 600Hz was connected after a 375Hz ie 975Hz. The sound was almost there close to the timbre.


Then a Pleiades filter of 1.27KHz (25mH) was connected, it sounded fantastic but perhaps a bit thin
as expected.


So a 100Hz Pleiades filter was connected to the previous setup making a cutoff frequency of 70Hz + 975Hz + 100Hz, roughly 1140Hz.


It sounded fantastic and almost right for this type of song and next to mic distance. At such small distance the output of the microphone is very high too making an added advantage.


The MD441 is a fantastic microphone. There wasn't the slightest "s" sibilant problem even at 0in while the voice of course was crystal bright and there was not the slightest background acoustic noise capture or any other noise like hiss. Pop was absent too due to,the excellent mic and the sampling of the voice coil at the low frequencies by the Pleiades filter.


Setup, signal path:


Male voice singing Going to a town at the original key - MD441 U3 at 0-1 inch - Pleiades 1070Hz - Canford 70Hz (400mH input transformer) - Pleiades V4, EF183 electron tube operating at 3.4 volts - Realistic disco mixer at mono mic in - Sennheiser HD580


The overall cutoff frequency indicates that the inductance needed to be connected to the mic is 27mH.


Why?


Because 200Ω divided by 2 divided by π=3.14 divided by 1140Hz makes 27mH.


It should be very easy to make such a Pleiades filter as the inductance needed is so low. With a Magnetec 073 core it should be just a few turns and everything can fit inside an XLR inline female to male adapter. The coil is connected to pins 2 and 3.


Or a Pleiades stepup transformer can be made with a few primary winding turns on such or bigger core. This makes easy to wind the secondary which can make a very high turn ratio in just 1-2 hours winding by hand.


The simplicity and quality becomes a joy.

Canelina the cat and the output impedance

One day Canelina found a little battery of 12V inside a garage door remote control.


She was very excited as now had the same voltage as the powerful battery of a car.


She thought she could power everything that operates with 12V. Her laptop, motors, fans, portable TV etc.


To her amazement she found it did not work.


Disappointed she bought with her friend the patient tortoise a voltmeter to check what happens.


Every time they connected almost anything, the terminals of her battery were reduced to very few if any volts at the speed of light.


Crying they went to the two wise seagulls on the beach who were standing carelessly on their favorite rock inside the sea.


They said it is the law of concervation of energy.


The voltage therefore drops inside the little battery.


The the world external to the battery it appears as if there is a resistor in series inside.


Every time we try to draw current there is voltage drop according to Ohm's law.


And what about the car battery?


It still has and internal resistance but it is much much smaller. So there is much less voltage drop when something is carefully and with all precautions connected to it and it works.


Microphones have usually and output impedance of 200 ohms.


Canelina jumped up with joy.


And they all started dancing on the beach while singing under the rays of sun that do not leave any shadow to truth.


Reference:


Electronics - Neil Storey

Possibly the most important video

The human race has problem in intuitively understanding the exponential function.


This vintage lecture by prof. Bartlett at Colorado university explains why crises of any kind happen before we take notice unless we know!

The most important video you will ever see - Bartlett
https://m.youtube.com/watch?v=DZCm2QQZVYk


Reference:


Conceptual Physics - Hewitt - appendix

How do resistors, capacitors, inductors work

Resistors convert electrical energy to heat.


Inside them flowing electrons collide with the larger molecules, give up some of the energy to them. Do the molecules vibrate more wildly and this means the temperature is now by definition higher.


Resistors are useful because they convert current to voltage if we think of the Ohm's law and look at it the other way.


So the varying output current of a device that amplifies a music signal for example can be converted to a voltage varying music output signal.


Capacitors store energy in the form of electric field.


Inductors store energy in the form of magnetic field.


When a voltage is applied to a capacitor through a resistor electrons start moving by repulsion from the negative terminal of the battery to one of the plates of the capacitor. The ones that have arrived there as they are negative repel following ones arriving too. The more they arrive the more difficult it is for new ones to come. Much like as soon as a room starts getting full.


This increasingly difficult situation is an non linear effect and the equations that describe voltage, current as a function of time are exponential.


Capacitors try to keep the voltage across them constant.


Inductors try to keep the current through them constant.


An inductor of large inductance is much like a train that it is hard to start moving and hard to stop, it reacts. This is why coils, inductors, and capacitors are described as having the property of reactance. Capacitors react to a change of voltage across their terminals.


References:


Conceptual Physics - Hewitt


The Feynsmn Lectures in Physics


Electronics - Neil Storey / later editions


Introduction to System Dynamics - Shearer, Murphy, Richardson - Addison Wesley

What is Temperature

Temperature is the manifestation of the kinetic energy of molecules, electrons etc.


When something is heated up molecules vibrate at larger amplitudes.


We get our energy from the sun. And it is the photos that collide with the earth, transfer their energy and heat us up. Otherwise the temperature would have been close to -273 degrees Celcius.


A nonlinear effect makes the equilibrium point to shift very little. But this shift of all molecules macroscopic all is perceived as expansion of the material. So we have the liquid inside the thermometer rising high.


Similar non linear effects demodulates the radio waves on AM so that the radio can extract the music content.


Similar non linear effects may take place in our basil membrane so that louder intensity of the same sound or tone appear lower in pitch to our brain.


References:


Conceptual Physics - Hewitt


The Feynman Lectures in Physics


Foundations of Wireless - Scroggie

On teaching yourself to distiguish (harmonics) overtones

Harmonics is an unfortunate term as almost nothing in nature is exact multiples of integer numbers.


The correct term is overtones.


Exact overtones of x2, x3, x4 in frequency may be heard by listening to 80s video game sound content.


Real good acoustic instruments and synthesizers depart from the exact multiples a little. This little makes all the difference.


To repeat. Real good instruments have an overtone producing structure slightly expanded in frequency and thus makes a tremendous difference to our brain perception.


For example, for correct octaves to our brain, the higher frequency must be a little more than double. For example if  an A of 440Hz has been played then 880Hz sounds a dramatically bad octave.  It may be for example that 882Hz sounds correct.


It also depends on intensity, ie how must acoustic energy is put out by the source of sound. Higher intensities give a flatter impression to our brain, ie lower pitch.


How can I prove all these to myself?


It is very easy, you can use any online signal generator, input the numbers and let your brain hear and decide.


And now to the topic.


The teacher for distiguishing overtones is the acoustic piano itself.


We play for example middle C, C4. We keep pressing the key even after the sound has completely decayed.


While still holding we play C5 ie one octave above for say 1 second only.


Although the higher note is released we keep hearing it on a well tuned piano.


What we hear in fact is the second overtone (mode of vibration) of the lower sting still held undamped. We can easily prove this be releasing now the middle C key and witness the C one octave above sound to stop!


We can repeat this experiment keeping again C4 held and then playing G5. This is the third overtone.


Then C6.


Then E6.


Then G6.


Then C7 etc.


The interesting fact is that now that we can hear the overtones of C4 individually, it becomes much more easy to distiguish them when the C4 note is being played alone.


All these notes on the overtone (harmonic) series of a correctly stretched sting at high tension is the basis of C D E F G A B , Do re mi fa sol la si or the C major scale from where most of our music springs.


References:


Discussions with piano tuner Albert Ketenzian


Musical Acoustics - Donald Hall


Waves - Berkley Physics Course


Lectures of Leonard Benstein on Youtube


Other euroelectron posts


Piano, Servicing Tuning and Rebuilding - Reblitz

Online sinewave or tone generator

Our ears, our brain


Sound and Hearing - Time Life Encyclopedia - Stevens


Hearing - Stevens and Davis


Octave Stretch - Ernst Terhardt - Euroelectron

On teaching your ear to recognize notes

This is possibly done by teaching yourself to play on the piano by ear.


Staring at a very young age, eg 5 years old helps a lot. This does not mean that it is not possible at other ages.


It is also the flight hours that count. At the beginning notes cannot be distinguished with their names, it is frustrating, but at some point everything falls into place.


It is important that the piano is tuned at the high correct pitch.


Playing together with recorded music is very important.


Perfect pitch may be an unfortunate term.


Distinguishing notes means that one can immediately identify that when for example 440Hz, 444Hz, 435Hz is being played that it is the note A or LA. Same with other notes.


It is very helpful as by more flight hours one can identify the harmony of a symphony or of a pop song by hearing the notes of the different parts simultaneously.


Music then can then teach itself even when one is outdoors and there's music being heard from somewhere.


Another fun exercise is trying to play a known piece of music or song by ear. One learns immediately by the mistakes. Melody can be tried first, then the bass using the left hand.  Then the chords or harmony. Harmony springs from the bass but is not nessasarily at distances of 3 or 5 as for example C bass, harmony C, E, G. In works of great ingenuity it has this but it also departs to any conceivable code. For example 6 (the 3rd is taken too), 7 prepared and the 3rd taken too, 9th prepared the 3rd is taken too. Example for 9th: An F sharp has already been heard, while this F sharp exists the bass becomes E and another part plays G or G sharp depending on which key we are. Example of unprepared 9ths is Hey You - Pink Floyd. Right from the beginning it alternates between E minor 9th and D minor ninth.

If one is stuck then the score can be read and this is the magic moment when we learn what we did not know and could not recognize by listening. Next time we can recognize.


A quick way to understand most of the already beautiful harmony on our planet is the C major prelude by J. S. Bach in the well tempered clavier. The composer takes us by the hand and explains how the game is played. A variation of this piece using the first few bars of harmony is Don't Cry for me Argentina. It is usually transposed to B or C sharp and a nice version is by Madonna.


On  distiguishing the (harmonics) overtones themselves on the next euroelectron post.

On teaching your ear to hear harmonics

This is described on the next after the next post.

Hit Song Ingredient: Harmonic Chain, example

This is a nice example of Harmonic Chain:


Going to a Town - George Mochael
https://m.youtube.com/watch?v=8DZJQjn3jV8


Harmonic Chain means the bass increases by 4 scale steps many consecutive times.


The sevenths are prepared and the third is added every time.


Harmonic chain can be seen in the transcription of The Oboe Concerto in D minor , 2nd movement - Marcello by J.S. Bach.


Reference :


Instructions for Playing Figured Bass - J. S. Bach (can be found at the appendix of the Bach's biography by Spitta). (Also called Percepts and Principles...or The Art of Music - J.S. Bach)

Phil Ramone, George Michael at Air Studios

Another great church studio.


Phil Ramone can be seen producing the song Going to a Town - George Michael:


https://m.youtube.com/watch?v=lhJ51Rz5t34


https://m.youtube.com/watch?v=8DZJQjn3jV8

Phil Ramone on recording The Girl from Ipanema

While Phil Ramine describes how he miked each instrument...


"I simply got down on my knees, and when I heard the right sound I place the mic"


Reference:


Phil Ramone Interview part 3 - Marc Myers - JazzWax - JazzFM91
http://www.jazz.fm/index.php/music-a-video-mainmenu/jazzwax-mainmenu-153/3937-interview-phil-ramone-part-3

Why does the saxophone sound much above the speakers on The Girl from Ipanema?

Could this be because Phil Ramone used a U47 above the bell of the sax and a mic down low near the bottom of the horn?


Could the interference (added signal) of the two mics have extracted, conveyed the height information? A similar way to how holograms work?


Reference:


Interview Part 3 - Phil Ramone - Marc Myers - JazzWax - JazzFM91
http://www.jazz.fm/index.php/music-a-video-mainmenu/jazzwax-mainmenu-153/3937-interview-phil-ramone-part-3


Signal path:


Sophisticated Ladies LP - Linn K9 MM cartridge - Linn Basik tone arm - Linn Sondek LP12 - Naim Nait 2 - KEF CS5 constructor series

The song Eternal Flame - Bangles, photos of Ocean Way Studios

The song Eternal Flame - Bangles has fantastic sounding vocals.


The vocals by the way they sound and the fact that the live version is a semitone down may have been recorded with Varispeed.


A search on Wikipedia revealed these beautiful voices were recorded at Ocean Way Studios.


This is no coincidence as the rooms were designed by Bill Putnam.


Another sound that quickly comes to mind is California Dreaming - The Mamas and the Papas.


Searching Ocean Way studios and then clicking images on Google reveals the Beauty.


All those panels should be for absorbing low frequencies by converting them to heat as the panels sympathetically vibrate? Are they made from linoleum? roofing felt? as on BBC and EMI studios?


Papers on studio design can be found by Putnam.


Also the story of Ocean Way when Allen Sides renamed them from United Western Recorders:
http://www.uaudio.com/blog/ocean-way-history/


There is of course a whole chapter on the studios on the excellent book referenced.


Reference:


Temples of Sound - Cogan and Clark

Changing the polarity of a microphone did not produce a change in sound

On Sony TCD5 pro II balanced in there was not a change in sound.


Setup:


D130 - Sony TCD5 pro II


Details on the next after next post.

Sibilant problem cause

Description on the next post.

AKG D130 and Electro-Voice 635a revisited

They were connected to an inline transformer with an input inductance of 220mH.


This transformer comes inside an XLR adapter in 2 versions. XLR female to XLR male, or XLR female to 1/4in jack.


The box on the first version says: Audio GSM 1, e+p Elektrik, 559423 Unna, Germany
The other one was bought without a box.


They both have a switch to choose from either 500Ω : 600Ω or 500Ω : 50KΩ.


The nearly 1 : (1 plus something) setting is very interesting too as effectively one has a Pleiades filter and at the same time a transformer isolating the mic while also stepping up the signal a little.


The Pleiades filter is made by the relatively low inductance itself and compensates for perceived increase in bass making the mic sound flat from vocal chords of singer to brain of listener.


The stepup option is very nice too.


Setup:


D130 or 635a - German transformer 1:16? - Pleiades V4, 3.4volts - Realistic Disco Mixer - HD580


With the 635a there were no s problems while with the D130 there were sibilant problems.


Then for another reason the mics were connected directly to Sony TCD5 pro II, (to check if phase makes a difference in sound on the Sony, and also whether the phase difference is due to interference from the direct acoustic wave and the wave coming from the headphones.


The Sony sounded the same on either phase connection.


Setup :


D130 - Sony TCD5 Pro II.Or
D130 - GSM 1 transformer at 500:600 - Sony TCD5 Pro II


The sound was very nice with the GSM trasformer on line for the reason explained above.


An interesting observation was that with the Sony recorder amplifier the D130 did not show any s problem.


The s problem happened only when playing back the cassette recording.


So it seems the s problem on the Pleiades setup comes either from V4 (not likely as it is the first stage) or the Realistic mixer overloading.


On the 635a there are no such problems on either setup. The D130 used has only its excellent metal mesh and nothing between it and the capsule. Is this how this microphone was originally made?


It seems the sibilant problem is an additive effect of mic and preamp combination. If for example a mic creates high spiky peaks, the problem is revealed in an amplifier with smaller transient overload headroom. More investigation is needed.

Variable Pleiades Filter

This is described in the following euroelectron post.

Autotransformer for adjustable microphone proximity effect filter

This may be considered a variable Pleiades filter with input transformer gain.


The variable autotransformer (variac?) is connected in reverse. The low inductance variable side becomes the input for connecting the microphone. The normal input to the autotransformer becomes the output.


It should be possible to adjust for any directional microphone, any microphone distance for natural auditory perception.


It may be thought as the analog to the focusing adjustment of cameras according to the subject distance or the macro adjustment for a close up distance.


Added advantage is the automatic stepping up voltage as the primary inductance is decreased.



This is why:


As a singer gets closer to the microphone more bass reduction is needed to compensate for the proximity effect.


Therefore less primary inductance is needed.


Therefore less primary turns are selected by the rotary knob.


Therefore higher turns ratio takes place as the secondary is fixed.


Therefore we have a stronger signal.


In fact there are two effects added while voice is made to sound natural.


The signal is stronger as the singer is closer x the high step up ratio (which further multiplies the signal).


This should give a very strong signal ready to feed an ultra low noise, (one electron tube) preamplifier such as the Pleiades V4 for unheard sentitivity, loudness and low noise. Microphones in general can sound much more full in sound when there is an active stage of just one electronic device as inside the Neumann U47 for example.


Setup, signal path:


Moving coil mic - autotransformer - Pleiades V4, Vb=3.4V - realistic disco mixer mono mic input - Sennheiser HD580


Balanced signal output should be preserved as the output of the autotransformer is a coil.


The reduced high frequency responce at very high turn ratios may be beneficial too as it would compensate for increased high frequency perception due to Flether-Munson and voice effort (curves) psychoacoustic effects.


So we have an adjustable way to create a flat frequency responce not from microphone to loudspeaker but from the vocal chords of actor or singer to the brain of the listener at any distance.


Small distance has the advantage of hiding most acoustic problems, including noise.

Polarity can make a change on balanced microphones too

Before dismissing a microphone as bad sounding it may beneficial...


To use a simple XLR female to male adapter that changes polarity or phase. This means 2 is connected to 3 and 3 to 2.


The effect seems to take place when feeding an external bs,an editor to unbalanced transformer.


In some cases the change is sound is so dramatic one is in for surprise. The difference can be described as from having a bad cold to super clean voice.


The effect is not very well understood.


Some new ideas may be here needed.


Setup, signal path:


200 or 500Ω balanced Mic - Canford, Sowter or other external input transformer, balanced to unbalanced connection - 1/4in jack - Pleiades V4, Vb=3.4V - Realistic disco mixer - Sennheiser HD 580

Making a healthy ice cream with Avogado, Φτιάχνοντας υγιεινό παγωτό με Αβογκαντο

At your own risk.


The idea is to make a mousse with Avogado, cocoa power, βασιλικούς χουρμάδες etc.


Something liquid, coconut milk?, coconut water? etc.


After blending it can go to the freezer.


Hint or idea by Angeliki at Juicitto fresh juice bar.

The most healthy ice cream ever made? το πιο υγιεινό παγωτό που έγινε ποτε;

At your own risk.


Bananas in the freezer.


Then in the blender with a few drops of coconut milk.




Hint given by Angeliki at Juicitto fresh fruit juice bar.


Another hint given by a friend of Angeliki is adding instead a bit of tahini or honey.

How to always be healthy and beautiful, handsome, Πως να είστε παντα νέοι νέες και όμορφοι όμορφες

At your own risk.


Με δίκη σας ευθύνη,.


This is elements of knowledge.


The best way is finding out yourselves.


A good rule of thumb is observing around you...


Observing, reading or asking those who have lived for many years and are still alive, beautiful, heathy looking.


You may find then:


They are up early in the morning letting the first rays of sun caressing and penetrating gently their bodies. Same with the sun rays during sunset. Avoiding of course watching directly the sun.


They are very careful what they sign and have realised that the less they have signed the more they have kept of their freedom.


They exercise free will.


They walk quite a bit and they exercise lightly.


They do things at their own pace and they do things they love most.


They are feeding with possibly the best ingredients on the planet. Excellent examples are whole grain sesame, whole grain tahini, great quality honey, walnuts, raisins, almond etc.


They are laughing even when the going is tough.


They are reading ingredients list with a magnifying glass like Sherlock Holmes on any food packaging.


So, they do not eat palm oil, palm fat, margarine, vegetable oil, fats, which have a reputation of cloging arteries. And those everywhere on almost any pastry, ice cream, ice cones, chocolate, croissants, nut cream, donuts.


Of course all these can also be made with top quality and usually expensive. ingredients.


Companies are not to blame. They do write ingredients on any packaging. It is up to us to read and decide what to eat and what not.


There is free will.


Pastries for example can be made with virgin olive oil, so bread too...


Our body is a temple. And in temples we enter clean. So anything that gets in our body.


They are avoiding the white. Flour, sugar, salt.


Beverages are out.


If they even get ill, which is unlikely, they use vitamin C from fresh fruits to cure or prevent. An example is lemon in a glass of water etc.


They drink fresh fruit juice that has ginger.


They use σέλινο that has a reputation or expanding blood vessels and is an aphrodisiac too for both sexes.


They filter water.


They breath fresh air as much as they can.


There are early in bed.


They live without a hurry.



They do not hurry on anything.


They do not work for money. They let money work for them.


They have realised that happiness, time, energy therefore money comes from only one source and is free. Our Sun. In ancient Hellas it was called Apollo, the God of light.


They do not fear anything as fear dies not even exist.


They do everything transparently under the sun.


Without hiding knowledge. By giving hapiness to others they take back too from any conceivable source or way.


They use imagination.


They do not use toothpaste containing fluoride.


They enjoy their occupation, anything they like.


They do not rush for things or anything, anyone. They let things come to them.


They are eating salads as a self contained separate meal. Linseeds seem to go nice on top of tomatoes. (There are many omissions on this posts. As less processed olives seems to be great for health. It is best that anyone finds for him-herself according to what seems to work well for their body, mind, soul.)


Virgin or sesame oil uncooked.


Fresh vegetables too.

Fibers for cleaning the inside of their body. Great example is 100% barley rucks. This may be the secret of them keeping slim, in great shape with no illness.


They get calcium from sesame and tahini and not milk.


They rub their body with clean hands or a dry towel every morning or night to get rid a gone cells, ie dust.


They enjoy life without rush. And life enjoys them.


Anybody who sails slowly sails far.


By the way a good way to make a healthy ice cream seems to be frozing a few bananas and then in the blender together with a few drops of coconut milk.


They are close to nature...


Watching the beautiful night sky too. Pondering on the mystery of Beaty.


References:


Life around us


Enchiridion - Epictetous - free PDF


Fringe knowlecge for Beginers - Montalk - free PDF


Tao Te King - Lao Tseu


Preventive Medicine - Karavis - Publisher Πύρινος Κοσμος, Προληπτική Ιατρική - Γιάγκος Καραβης - Εκδόσεις Πύρινος Κοσμος

Pleiades modular microphone

It may be possible to have a self contained world class moving coil microphone with its tube preamplifier and battery inside the same mic housing structure. Advantages high output, unheard sensitivity and low noise, amazing sound quality.


The constituent elements would be as follows compared to a Neumann U47 for example:


Neumann U47 simplified:

Condencer capsule - High Megohm resistor - VF14 tube - output trasformer
External power supply


Pleiades microphone:

Moving coil capsule (removable) - step up transformer - capacitor coupling - EF183 tube with 4ΜΩ from plate to grid - 3.7 volt li ion battery - output transformer directly to anode (plate)


The 4MΩ resistor neutralises the self assumed negative grid voltage as explained in reference 3. This frees electrons from the cathode cloud and makes possible the operation of the electron tube at 3 volts. A typical value of input impedance is 100KΩ.


An advantage is extremely low noise.


Another advantage is that no high voltage is needed for magnetic moving coil capsules. The magnetic filed is supplied by the permanent magnet.


Therefore there is no need for a DC to DC oscillator for stepping up, or other source of high voltage.


The EF183 electron tube operates at a phenomenal signal to noise ratio using 3.7 volts (practically no secondary emission effects) as on the Pleiades V4 preamplifier.


The heaters are underheated as on the VF14 amplifier of the U47 to extract maximum information with least of noise. So they are supplied from the same 3.7 volts battery source.


Electronic cigarette type li-ion batteries of 5000mAh for example would give plenty of hours of operation.


Of course this amplifier could be used for any other dynamic microphone or capsule.


Moving coils mics are usually 200Ω or 500Ω so cables can be of any length unlike condencer capsules which have to be next to the electron tube of JFET.


A variation of the Pleiades microphone can be with a JFET amplifier such as the K117 as on the Pleiades K117 preamplifier.


The Pleiades microphone may have the posibility of interchangeable moving coil capsules.


A useful protocol may be that the female input on the microphone for any capsule being a standard XLR female connector.


The capsules would have a male termination as on talk back microphones.


So the Pleiades microphone system would be compatible to connecting any microphone even ribbon
ones to its input using a cable of any length or directly.


Other options include phantom powering. Or USB powering as the electron tube operates only with 3.7 volts at about 220mA.


There can be possibility of digital out, making it a digital microphone.


It may be advantageous to have everything in modules so any configuration may be possible. For example: Various moving coil capsules of any polar diagram - input transformer modules with Pleiades proximity degree of compensation for any distance - electron tube or JFET preamp module - analog go digital converter module - iPad lightning connector module etc.


Modules can be made inside Neutrik XLR modules or otherwise.


Suitable cores for the Pleiades transformers are the superb Magnetec Nanocrystalinne Nanoperm tape would cores of extreme inductance index requiring relatively very few turns.


The extreme high signal to noise ratio, the quietness of the battery and the dynamic and smooth sound of the electron tube will make the system suitable to be connected to any other microphone preamplifier as we would connect a Neumann U47 with its high voltage output, low noise and pristine sound quality.



The development of this and any Pleiades concept is open source, public domain, free.




References:


Neumann U47 schematic


Pleiades V4 schematic


On preserving transconductance of electron tubes at anode potential as low as 3 volts
http://euroelectron.blogspot.gr/2017/03/on-preserving-transconductance-of.html

A fundamental difference between moving coil and condencer microphones

For flat frequency responce moving coil microphones must have the diaphragm vibrating at constant velocity as frequency rises.


For flat frequency responce condencer, crystal and carbon microphones must have the amplitude of the diaphragm constant as frequency rises.


This is because moving coil microphones operate on the principle of magnetic induction, voltage is proportional to the rate of change of magnetic lines cut by a moving conductor.


Constant velocity means that as frequency rises the displacement of the diaphragm must be arranged to be progressively smaller.


So the reasonant frequency of the diaphragm on ribbon and cardioid moving coil microphones is placed at a low frequency. As we ride on the right of the curve of this reasonant frequency diaphragm excursion is reduced.


The reasonant frequency on pressure (omnidirectional) moving coil microphones is placed at mid band and it is damped.


The reasonant frequency on true directional condencer microphones is placed at mid band and it is
damped.


The reasonant frequency on pressure condencer and crystal microphones is placed at a high frequency.


Reference:


Microphones - Bore, Peus - Neumann - free PDF


Microphones - Borwick - Focal Press


Microphone Manual - Huber - Focal Press


Microphones - Lou Burroughs - Electro-Voice


Sound Recording Handbook - Woram - Sams.

How to find and read patents Πως βρίσκουμε για να διαβάσουμε πατέντες, ευρεσιτεχνίες

We just write on Google US followed by the number, USxxxxxxx if it is a U.S. Patent.


We can also search at the U.S. Patent office online or European, espacenet etc.


We can learn how almost everythingt around us operates and how it is made.


Γράφουμε απλά στο Google US και μετά τον αριθμό της πατέντας, πχ USxxxxxxx αν ειναι αμερικανική.


Μπορούμε επισεις να ψάξουμε στο US patent office μέσω Ίντερνετ η στο Ευρωπαϊκό, espacenet.


Μπορούμε να μάθουμε πως σχεδόν οτιδήποτε γύρω μας πως λειτουργεί και πως φτιάχνεται.

There is Hope

Why does the Beyer M55 microphone sound so natural?

So far it is tested mostly on male vocals at very close distance and it sounds amazing.


Why?


1. On pressure moving coil microphones the reasonant frequency is placed right at the mid band and is damped so that the microphone has flat frequency responce. Not at a low frequency as on cardioid moving coils, or ribbons. Or at high frequency as on omni condencer microphone capsules.


2. So the mic is inherently insensitive to blasts, pops and is smooth sounding at the high end too.


3. It does not seem to have the high frequency peak due to the pressure doubling effect of other omnis as it seems to be designed for flat free field (direct sound at 0 degrees) responce rather than flat diffuse field responce.


4. Diffuse field responce does not seem to matter much as the point here is getting as much clean sound electrical signal as close to the microphone. Same reasoning for outdoor or large studio recordings where the diffuse sound comes apparent at much larger distance (reverberation radius).


5 So as it behaves greatly at very small distance the signal is strong even at week voices and the signal to noise ratio is a joy to hear or rather not to hear.


6 Voltage output is large as it is 500Ω.


7 It does not need extra Pleiades filters to reduce increased bass perception due to Fletcher Munson and voice effort curves. It sings naturally with a typical inline input transformer of about 400 millHenries primary inductance.


8 Similar argument for its inherent high frequency roll off compensating for increased high frequency exaggeration due to Fletcher Munson and Voice effort curves. (These effect take place because on pop music the chosen reproduced acoustic level of voice is much louder than (reallity)). It therefore sounds flat not from microphone to loudspeaker but from vocal chords of singer to listener's brain.


9 It has due to its excellent design virualy no sibilant problems even at 0-1in from voice source.


10 It makes an extremely simple signal path. Example: Voice coil to input transformer to capacitor coupling to the grid of an electron tube preamp, such as the Pleiades V4 and it is fantastic.


There may be much more reasons, perhaps it is time to visit online the patent office and read some Beyer patents.


References:


Microphones - Bore, Peus - Neumann - free PDF
http://www.neumann.com/downloadmanager/d.php?sid=10ui5hmm8ktkfv3q1a59jhgt53&download=docu0002.PDF


Sound Picture Recording and Reproducing Characteristics - Loye, Morgan - Journal of Society of Motion Picture's Engineers - 1939 - Hollywood, California

What is inside the Neumann Dummy Head?

A very interesting paper by Stephen Peus explaining the improvements on the more recent Neumann dummy head:


Title: Natural listening with a dummy head


Translation by Stephen Temmer


Here is the link:


http://www.neumann.com/downloadmanager/d.php?sid=ivtl2hvet9fcekg29lapocmgi1&download=lect0025.PDF


Another interesting paper by Neumman is: The Dummy Head - Theory and Practice


It explains as well free field and diffuse field equalization


http://www.neumann.com/downloadmanager/d.php?sid=ivtl2hvet9fcekg29lapocmgi1&download=docu0009.PDF


And also:


 Microphones - Neumann by Bore and Peus


http://www.neumann.com/downloadmanager/d.php?sid=ivtl2hvet9fcekg29lapocmgi1&download=docu0009.PDF

Increase in very low frequency noise perception when one ear is closed

This was observed by chance.


It started off as a test on how accurately two different microphones, each one in turn, would capture outdoor ambient full spectrum noise.


Each microphone was in turn placed near an open window.


Quality was judged by listening to headphones and comparing this to how the ambient noise sounds using our own ears, head close to the window.


At one point the right hand covered the right ear. Therefore only the left ear which was close to the window would hear the ambient noise.


A dramatic increase at very low frequency rumble was perceived. It disappeared when the right ear was uncovered.


This low frequency content seems to be in the region of 10-30Hz.


The experiment was repeatedly performed with the same results. The outcome was the same in various areas including indoors. At some point an earplug was placed on one ear to exclude the possibility of hand induced vibration.


So it appears that when both ears are on there is some cancelation mechanism of this disturbing noise.


Is this another reason why a single microphone when no bass filter is added captures so unnaturally and exagerated very low frequency content?


It seems it captures what is there.


But we humans have a mechanism of canceling this disturbing sound.


A low cut to perception when we use both ears?

Understanding by feeling inductance, impedance, resistance etc

Impedance is by definition the ratio of voltage across 2 points to the current that flows through them.


Voltage and current are vectors, so impedance is too.


How come and they are vectors?


When we talk AC, ie vibrations, or oscillations, they not only have magnitude but also phase.


They are complex numbers having a real and an imaginary part.


How come?


AC means sinusoidal oscillation.


Imagine holding in our hand a LED torch.


We then make a perfect circular motion with our hand but we always point the torch perpendicularly to the wall.


We see the light projection creating a perfect sinusoidal oscillating motion on the wall.


The radius of our hand is the amplitude of this motion.


The angular velocity is analogous, proportional to frequency. This is why the angular frequency equals to 2 times PI (3.14...) times frequency. Or ω=2πf.


And the angle our hand makes at any particular moment is the phase.


So, circular motion is a very convinient way to represent vibration, oscillation.


Our hand moves on a plane.


The torch in our hand is at any particular instant at a different 2 dimension point.


The x axis is the real axis. And the y axis is the imaginary axis.


This is why we need complex numbers, ie vectors or numbers of the type (a,b), or a+jb, or e to the power of jωt where t is time or rotating vectors or phasors. They are more or less the same thing.


Impedance also exists of course on mechanical systems, acoustical systems etc.


On mechanical systems it is defined as the ratio of force to velocity.


On acoustical systems as the ratio of pressure to air velocity.


Back to electrical...


Current and voltage may be not be in phase. This happens on capacitors and inductors.


The same on mechanical systems. This happens on masses. And springs. Mass is the analogue to inductance. And springiness is analogous to capacitance. A spring is the analog of a capacitor. The capacitor tries to keep the voltage constant, the scoring tries to keep the force constant.


They obey exactly the same equations.


It is expected since they behave in exactly the same way.


By Newtons 2nd law, mass tries to keep its velocity constant and opposes changes by creating force or vice versa. (It is not easy to accelerate or stop a car).


Same with inductance it tries to keep current through it constant and opposes changes by creating voltage.


This is why an inductor in series cuts treble or high frequencies and an inductor in parallel cuts bass as on Pleiades filters. It has a lower impedance the lower the frequency is and causes a greater voltage drop at the output of a microphone. This is because a microphone has a non zero output impedance usually 200 ohms. So there is an internal voltage drop at the mic due to ohm's law.


On resistance the voltage and current are in phase.


Same on mechanical resistance or friction.


If we oscillate our palm on the beach by rubbing sand we can feel that force and velocity are in phase.


We can also feel that impedance is independent of frequency.


The same with electrical resistance of resistors on an electrical or electronic circuit.


But not so for inductance or capacitance where the reactance, (the imaginary part of impedance depends on frequency).


Why imaginary part?


Because the cause and effect are 90 degrees out of phase.


We can feel this in a very easy way on mechanical systems.


On sand as we said we feel force and velocity in phase.


But not on mass which is the equivalent of inductance.


Try for example holding in your hand something that has mass.


If we oscillate our hand at a low frequency it is easy but it gets progressively difficult the higher the frequency we want to produce.


This is a high cut filter together with the driving output impedance of ourselves.


If we try to do the same to a door which has a much higher mass we further feel this. And we have a high cut -3 dB point (amplitude drop of door oscillation) which happens now at a lower frequency.


This is inductance in series.


Or rather mass.


And we can readily feel that the sinusoidal force we apply and the sinusoidal velocity are not in phase. it may not be 90 degrees as there is friction too or resistance and we have to add vectors!


Analogous things happen with capacitors and springs, and volumes of air of bottles. And necks of bottles.


And when capacitances and inductances are connected we have electrical oscillation. Electrons move back and forth.


Same as when mass and spring are joined where we have mechanical oscillation.


Same as on a bottle. The mass of air in the neck behaves as mass or inductance trying to keep flow constant. The volume of the bottle like a spring or capacitor.


And when we carefully place our ear at the neck of the bottle we can hear the resonant frequency and if we blow we can produce a sustained oscillation.



References:


Introduction to System Dynamics - Shearer, Murphy, Richardson - MIT - Addison Wesley


Music Physics and Engineering - Olson (Staff Vice President Acoustical and Electromechnical Research, RCA)


The Feynman Lectures on Physics - Feynman, Leighton, Sands - Caltec - Addison Wesley

3 very important principles in Nature

The conservation of energy.


The conservation of momentum.


The direction of entropy which is the arrow of time.


Reference:


The Feynam Lectures in Physics - Addison Wesley


Richard Feynam Lectures on YouTube

Grundig GDM311 part 2

What a great mic !


Another specimen was tested. There seems to be great sound variation from different specimens.


As natural sound as one could expect.


Some sibilant problems when used at very close distance.


If it sounds very bad it is likely there is something wrong or the polarity needs to be reversed.


With the correct polarity it sounds very clear, surprisingly so.


If it sounds thin on the 200Ω terminal, the cause is the following:


It already has an internal autotransformer of low primary inductance, ie a Pleiades filter. The low inductance together with the output impedance of the voice coil introduce a low cut so that the mic sounds correct to listener's brain.


When it is connected to an amplifier with an input trasformer of relatively low input inductance (ie 400mH) there are then two coils (inductances) in parallel. So inductance becomes even less and the the mic departs from natural and sounds thin to listener's brain.


If it is connected to a transformer of very high input inductance such as Sowter, Jensen etc (4H to 10H) the sound is great.


Alternatively one can use the high Z out of the internal autotransformer and connect to grid of electron tube (possibly through capacitor) or gate of JFET. The sound is then fantastic. The trasformer has an unusually high turns (step up) ratio. It may need termination for damping. The Pleiades V4 used does this automatically.


The sensitivity then is so high one can hear sounds from hundred of feet away.


And the mic still sounds full and natural when one speaks or sing at 1 inch distance.


Setup, signal path:


Grunding GDM311 - Sowter 3104x - Pleiades V4 at 3.4V - Realistic disco mixer mic mino input - HD580


Or


Grundig GDM 311 H connection - Pleiades V4, 3.4Volt - Realistic disco mixer at mono mic input - Sennheiser HD580


The capsule seems to be low impedance, 10-30Ω? .


It is stepped up by an autotransformer to 200Ω or 30KΩ.


The primary inductance of the autotransformer is very low, typicaly 10mH.


This is to remove the exagerated low frequency perception to listener's brain.


If more body is needed one could experiment and wind a Pleiades trasformer using a Magnetec Nanocrystalinne Nanoperm tape wound core. One could then increase the body of sound and tailor to what is needed at any impedance.


It seems to be The mic for ASMR as it sounds fantastic at 0in and 2 can make a great binaural pair if two are placed next to one' ears while recording.

Hit Song Ingredients Part 3 Code

Code is used at any genre of music on sophisticated examples.


It is when the distance of the upper parts from the bass note departs from the obvious 1 or 3 or 5, basic major or minor triad.


An obvious example is the 80's hit song:


Maria Magdalena - Sandra (in B Dorian scale (C,F,G are sharp))
https://m.youtube.com/watch?v=epHOF91ZUFk


Even the first note sung by Sandra departs from 1, 3, 5.


When she sings "You...", the note is A. At that moment the bass is B.


So the interval by counting the notes of the B Dorian scale: B C D E F G A is 7.


Having (first thing in a song) a 7th interval may be even more rare than classical music.


The next change in bass is F sharp. At that time Samdra says the first part of "Love" using G sharp resolved to F sharp. This is an interval of 9 found in the best examples of music on our planet as on J.S. Bach's music.


The song travels us to various code non obvious intervals like 6ths etc.


And it is nice and simple with simple instrumentation and few important voices like Vivaldi.


No wander it became a great hit in Europe in the 80s.


The song may also use the hit song ingredient Varispeed to further freshen up the timbre of the voice.


Bravo, thank you Sandra and Michael Cretu.


References:


The Art of Music, or Instructions for Playing Figured Bass or Percepts and Principles - J. S. Bach


Musical Acoustics - Donald Hall


Young People's Concerts on YouTube - Leonard Bernstein

Fourier Transform of EEG

For an attempt to explaining what the Fourier transform is or how something looks in the frequency domain rather than in time domain please refer to the following euroelectron post.


Has this been done on EEGs?


Would it be useful?


How would the signal of an EEG sound like if we speed it up in time domain so that we can hear the low REM frequencies? This may be done by recording and then increasing the playback sampling rate.


Reference:


Waves - Berkley Physics Course

Fourier transform for stock exchange price charts

Has anyone made a Fourier transform of a stock price graph?


Would it be useful?


What is Fourier transform?


It is a mathematical operation, now performed easily using a computer, FFT, that converts time domain to frequency domain.


Stock prices are in time domain, as the x axis is time. The Fourier transform of this is price with respect to (the x axis now being) frequency. Equivalent information.


Peaks at high frequency for example would mean that the particular stock has a tendency to vary very quickly.


A better way to understand is in music.



A music signal is vibrations. We can readily feel these if we touch our laryng while singing. Low notes have a low frequency. High notes have a high frequency. If we look at the vibration as amplitude displacement with respect to time it looks like any quickly varying graph.


The Fourier transform of this is what notes are being played. What we might see watching a spectrum analyzer while singing.


Like the keyboard of a piano, left notes are vibrating at lower frequency than the next note on the right.


This is frequency domain.


Reference:


Waves - Berkley Physics Course

How balanced signal transfer operates

It is two conductors that carry the signal.


Example:


The two conductors connected to the voice coil output of a microphone.


At any instant when electron move to one direction on one conductor, say towards the preamp the electrons on the other conductor move away.


We must not forget it is not electrons that move from microphone to preamp.


They just oscillate about a point with a motion mimicking the vibration of music. Like dancing. The electrons on the other conductor do exactly the opposite as a mirror.


It is the electromagnetic wave (the cause of movement) that moves from mic to preamp at the speed of light in the material of the wires.


Same as on the sea waves. The water oscillates back and forth. It is not water that travels, it is the wave, by definition the transfer of energy. The water is not transferred from sea to shore. It stays where it is.


Back to balanced...


Electrons repel each other. The ones vibrating repel the nearby ones to vibrate too at the signal of music. The next ones near by vibrate too and so on. Until the cause (the wave) arrives at the input of the microphone preamplifier.


Electrons arriving at the live pin (2) have a mirror motion from those arriving at pin (3) of the XLR connector. If the signal goes to an input transformer when electrons on one side of the primary winding go in, electrons from the other side exit. So it is like moving a towel back and forth with our hands while drying out hair. The balanced motion aids the action.


But if there is an external interference signal arriving somewhere along the cable, it will be pickup up equally by both conductors which are next to each other. Electrons will have almost exactly the same motion, so whatever motion they have at any instant they will collide when they enter the input transformer. In fact if you think about it is the cause or 2 waves that collide.


So interference is out while music is in.


For obvious reasons the two wires are twisted, so hugging each other they have the same experience of the environment.


The shield is an extra precaution. It hugs them both. Apparently it reflects electromagnetic waves arriving externally. In reality what happens is that somewhere near or far electrons may oscillate with an unwanted noise interference signal. Jealous electrons at the screen do the same. And the electromagnetic wave is reflected like a sliver coated mirror does. Whatever happens jealous electrons do not see what happens outside. So they are not inflicted by the interference. And concentrate romantically dancing in a balanced way to music.


Reference:


Feynman Lectures in Physics


BBC notes on how balanced twisted pair signal transmition operates (exact title not recalled, internal instructions)

A cartoon with super market bags ??

AKG MI 201-100 microphone

Another great sounding microphone


Omnidirectional.


Some s problems. Later addition. Not sure if they come from the mic or the following amplifiers.


The microphone has 800Ω output impedance. Layer addition. It was measured to be 667Ω. After a few day it was measured again 830Ω. Possible aging electrolytic capacitor effects on the Escort LCR digital meter.


On the following setup, sound quality was greatly changed by connecting in either polarity. It seems to be an electrical effect than acoustic phase effect that needs to be explained. Late addition. Possibly just phase with respect to the phase of the monitoring headphones when monitoring in real time. A phase inverting adaptor solves the problem.


The Sotwer transformer used synergies very well as it goes very low in frequency and the microphone does not. So together they give a flat frequency responce from singer's vocal chords to listener's brain.


Setup, signal path:


(1-3inch) - (AKG MI 201 - 100) - Sowter 3104x (1:10), input inductance 3.9H - Pleiades V4 at 3.4volts - Realistic Disco Mixer mic mono input - HD580


Great sound when the mic is used very close, full body and detail. It sounds so natural like an acoustic transmission line.


The Beyer M55, at close distance vocals needs an input transformer of only about 400mH input inductance to sound correct to listener's brain as the 400mH introduces the desired low cut together with the mics 500Ω output impedance. (Later addition, more than 400mH, ie of the order of 1.7H may be needed. The transformer measured exhibits a much higher inductance at low frequencies due to the magnetic material used, see other posts.) It then sounds amazing.  No sibilant problem. Many commercial inline low to hi Z transformers already have this order of inductance. A Pleiades transformer can be made using relatively few turns with a Magnetec Nanoperm Nanocrystalinne tape wound ring core.


The AKG MI sounded fantastic on piano.


Just by being placed on top of an upright piano with its tiny plastic support stand.


Setup:


L channel - Beyer M55 -

                                             - Sony TCD5 Pro II - HD580

R channel - AKG MI 201-100 -


The piano was played softly.


So expression was captured and the sustain and clarity of high notes was a joy to listen to.


Later addition 18101218


It sounds very natural just connected to the amazing Uher 4200 report portable reel to reel. See a forward in time euroelectron post.


It sounds great directly connected to Sony TC-D5 Pro, the Sony used in real time as a mic amp and headphone drive amp.

Proximity effect compensation or parametric EQing using 2 microphones

At your own risk.


Both mics can be literally connected in series and one mic is connected out of phase.


We sing to one of the mics and the distance of the other is varied.


It worked great on the following setup using the omnis MD21 HL. It may be possible with directional mics and by connecting to an adding (mixing) desk. On the omni mics although there is no proximity effect the bass was reduced to restore flat frequency responce from vocal chords of singer to brain of listener.


(The live output of one mic was connected to the live of the other, (for phase difference) the 2 remaining pins were the output of the combined mic and were connected to the live, return input of an XLR).


Setup:


+MD21 in series with (-MD21) - Canford input transformer - Pleiades V4, 3.4volt - Realistic Disco Mixer mic mono input - Sennheiser HD580


When two mics were connected in phase it is also very interesting as now the combination appears as a mic quite a few times as strong and noise quiet compared to a single mic and the impedance becomes 400Ω!


There must be comb filtering at play too and it can be used constructively to get the desired sound by varying the distance of the far from source mic.

How to balanced connect the MD421 HL HN MD21 HL HN M55 HL HN

All these microphones are balanced too.


They have an autotransformer to step up the impedance if needed but this does not change much.


If one looks at the schematic or measures the pins with an LCR impedance meter:


The voice coil (low impedance) is directly connected to 2 of the pins. So there are balanced as a voice coil is by definition balanced.


The high impedance part of the autotransformer (full coil) is also connected to 2 pins so it is balanced too as it is a coil too, (the only difference being it is a coil of more turns outside of the microphone voice coil).


In the above situations a pin is common to avoid the use of 4 pins. So everything is done on a Tuchel 3 pin or DIN 3 pin in the case of the M55. Same reasoning applies to the Grundig GDM311.


To summarize:


An autotransformer has 3 terminals.


The first two terminals are connected to the voice coil and the 2 output pins.


The end of the winding hi Z terminal is connected to the other pin.


It follows the other side of the auto winding is common. This is by manufacturer convention connected to the central pin of the output connector.


It follows the other pins are low Z and high Z.


The metal part of the microphone is not internally connected to any of these pins and this is good news for maintaining balanced output.


To summarize again:


There are 2 output options. The voice coil itself and the full autotransformer winding. Both are floating windings so they are balanced.


The fact that the voice coil is also connected in parallel with the low Z part of the autotransformer is not bad too as the latter acts as a Pleiades filter cutting some low end and making the microphone closer to flat (to listener's brain) frequency responce when singing is performed for example. It also electromagnetically damps the membrane making an effective pop filter.


From the above it follows:


To connect as low Z to XLR:


The central Tuchel pin is connected to either pin 2 or 3 of the XLR.


The other (low Z) terminal of the Tuchel connector is connected to either pin 3 or 2.


There is a fourth cable or connection. This is the metal part of the microphone and it is naturally connected to pin 1 of the XLR.


A very easy way to remember the XLR protocol is to remember 1,2,3 equals X,L,R, equals Xternal, Live, Return. So pin 1 is shield and the other pins are the signal pins, 2 being the live pin. When we design and make our own preamplifiers the chassis female XLR pin 1 must be connected to the 4th (nearest pin) which is the metal part of the chassis. In this way the microphone metal part is connected to the metal chassis through the cable shield. So everything is shielded and quiet. More information on the Jensen transformers website pin 1 literature. The chassis of equipment must be earthed for safety too.


You may experiment with swapping pins 2 and 3. It changes absolute phase but on some mics and preamp configurations it also may change the sound dramatically. A way to hear the difference is singing directly close to the microphone.

Electron's day, Photon's day, and Microphone's day

Is there an Electron's day?


They do so much for us.


They keep our body's shape, they make synapses in our brain work, they make us float when we swim. They make any chemical reaction happen. They make internet possible together with photos which supply the energy so that electrons can move and carry the information. They make wireless communication possible, satellite, mobile phone, radio, recording, storing and playing back music...


Is there a Photon's day?


They do so much for us.


Without them the temperature on the earth would be -273 centigrade? They bring the energy from the sun to us. They hit the leaves giving energy to the clorophyl molecule. It is big and when it collides (like a car having kinetic energy) with CO2 it separates C and O2. So we have Oxygen to live and love and love. Without them we would not have been able even to ask the question. Like electrons
they never go on strike serving mankind with love.


Is there a microphone's day?

They convert air molecule vibration to electron vibration. So voice, sound and music can be recorded, stored, transmitted. Without them we would have silent movies, and silent mobile phones. Silent CDs and we would not be able to listen to Silent Night on MP3.


Proposed Microphone's day the 1st of May.


References:


The Feynman Lectures on Physics - Addison Wesley


The Cell - Life Science Library


Sound and Hearing - Life Science Library