Is Varispeed used on song Don't Speak - No Doubt

At your risk. By listening to the CD single, the famous track sounds on C minor. Then track 2, the simple kind of demo version sounds on B minor. On Bminor the voice is more like the voice of a normal human being, and it sounds a bit out of tune, ie a bit lower in pitch than needed. So a special Tascam bass player practice CD player was used to Change the not so nice B minor track to C minor and it immediately sounded more ethereal , the singer younger due to time antiexpansion, plus the voice more in tune. Simmilarly the good Cminor master was changed to B minor and it sounded much inferior. Same experiment was done with radiohead, for example Creep. if playback is reduced by 1 semitone the excellent singer sounds still excellent but more like a normal human being. Do these experiments sugest that in some cases when the singer is to sing, the pitch of the backing track is reduced by 1 semitone, then at playback back to normal so effectively only the vocal is increased by 1 semitone with corresponding change in timbre. Listen also to To France, Moonlight Shadow - Mike Oldfield, Christophe, Demis Rousos, Sleeping Satelite - Tasmine Archer, ABBA. So far i have found bibliographic evidence only for ABBA, the book Good Vibrations-Mark Cunningham.

Listenung to some Hellenic song productions by Minos EMI

Had the chance today to listen to a compilation Cd called Ta Soukse Tis Nuxtas (the hits of the night). The sound quality was very nice, sparkling voices, and voices not out of tube, ie nice intonation. Not much bass heaviness to voices. Pehaps the low end of the recording was a bit exagerated. (Immediately afterwards Creep by radiohead was listed too. The voice is amazingly recorded but the low end of the instruments still sounded a bit heavy.) Well done to Mr Makis Matsas and his team.

Bingo! An electron tube microphone booster preamplifier operating with a AA 1.2V and a 9V battery

AT your risk. After countless experiments spanning almost 45 years assuming i started at around 7 years old... i used an electron tube for audio no one in their right mind would choose to use... A pentagrid ie heptode electron tube usually used for frequency convertion at rf receivers. Wanting very low energy consumption the D series of battery tubes was chosen. So there it is DK91 found waiting at Pleiades lab. Pentagrid tubes have 5 (pente in Hellenic) grids. So the 1st should be very near the cathode, and the second too. Using Wago connectors 1.25V was supplied at pin 1 and 7, ie the direct heaters or cathode. Then 9V was connected to grid 2 which is also internaly connected to grid 4. The current meter immediatly measured about 30 microamperes which is amazing at such low Vb and grid 1 at space potential (ie connected to nothing). With Vb=18V Ig2 increased to 500 microamperes which is aaamaaazzzinggg! Greatly incouraged, today, a Sowter special quality octal base 1:5 input transformer was connected to grid 1 trough a 0.010 microfatad capacitor. 9 volts through an output transformer. A 8.2 Megohm resistor connected to grid 1 for biasing (unconnected means grid at space potential, then if needed it can be connected to the negative terminal of the 1.2V battery or the positive terminal for even more anode (g2) in this case current. Connecting this resistor to the anode was found to be unecessary. The output transformer was connected to the mic input of Sony TC-D5 PRO. It worked nicely! The sensitivity was such that even touching the mic cable produced whistling sound, before connecting the SM58 mic. Mic was used at very soft voice 24in from mouth which is a nice distance for good quality sound, 30 degrees above head. WIth grid at space potential sound was about right with much high frequency detail. With resistor connected to Vf minus there was more bass heaviness as the output current increases and the tube plate resistance decreases, and with R connected to Vf positive side, even more bass for the same reason. (This effect naturaly comes from interaction of the output impedance of the electron tube with the input inductance of the output transformer dictating the low frequency cutoff. As frequency is decreased said inuctance becomes more of a short circuit so bass is reduced the higher the output impedance of the driving electron tube) Yesterday the same electron tube was used to directly drive the Sennheser Hd580 headphones through said output transformer, electron tube driven by the usual Sony CD walkman kine out. The headphones could be driven even with Vb 9V, more with 18V but the sound was very nice at 9V with R connected to the negative terminal of the 1.2V battery. Song used was To France - Mike Oldfield But back to today's mic expewriment. After disconnecting mic a 0 ohms specialy made male Neutrik XLR was connected. hiss droped to almost zero. Same withy a 200ohms XLR. Difference cannot be heard yet as there was a lot of hum picked up by the non mumetal protected output transformer. It would be nice to have such a pre preamp in a nice box with octal bvases for shielded input and output transformers. Powere consumption is only 1.2V at 50mA, ie the heater power supply plus 9V at say 50 or more microamperes ie the anode power supply. So little more than 60 milliwatts! If more such electron tubes are used in order to be able to drive say HD580 headphones then more power would naturaly be needed as the output electron tube may need more anode current or anode voltage, please protect very carefully your precious ears from high sound presure levels.

The most offen used electronics book at Pleiades lab

At your risk. It is the french Radio Tubes - Aisberg E., Gaudillat L, Deschepper R A schematic of usual application for any electron tube!

The best amplifier is no amplifier

At your risk. Sennheiser HD580 300Ohms headphones can be connected to line out through any good quality say 10KOhms to 300Ohms transformers. If signal is too high please protect your precious ears by using an attenuatos. (in fact on this experiment there is of cource the DAC output amplifier). But what if at the current output pins we connect the headphones directly through only 2 output transformers? This is what we were discussing recently with Panos.

Measuring from 20Hz up to say many MHz with any digital multimeter

At your risk. DMM are nice small, consume little energy but most ofter fail to measure above 3KHz. So here is what to do, the idea and schematic came from a vilntage transistor Philips micrvoltmeter able to measure up to many hundreds of MHz with its simple RF probe. The probe converts AC to DC. What can we use to do this up to a very high frequency? A Germanium diode! Here is the description of the schematic. Signal to be measured passes through a small high voltage capacitor. Then a Germanium diode is connected shunt to ground. Then on top a series resistor of 100Kohms buffers and its other side is connected to the high impedance DC voltage meter! So frequency responce tests can be done easily and lightweightly.

The directional microphone proximity effect does not noly exagerate bass, but mid bass, mid frequencies too

At your risk. Is this why many Hellenic vocal song recordings, both male and female sound so differnt from those made abroad? Are the mics here used too close and uncorrected for bass, mid emphasis? This again became very apparent while listening very early morning, LOVE FM radio station in Athens which plays both types of songs. the difference became very apparent on the Sony ICF-7600A radio with the tiny mid, treble speaker. Curves for bass, mid proximity emphasis can be seen on the Neumann, Microphones book by Bore, Peus. Please see link delow: https://www.indigo-music.com.ua PDF by G Boré · Cited by 15 — Gerhart Borй studied electrical engineering in Munich and Aachen, and specialized in microphone development at Georg Neumann GmbH from ... Peus and 0. Kern ... 79 pages

The Pleiades 2 K117 microphone preamp withh tiny input and output transformers did not record nice

At your risk. Possible reason is thye tiny transformers used which gave a frequency response resembling old telephone speech. This became very apparent after listening to a recording on the Pleiades 2N3053 power amplifier driving the Celestion Ditton 150 speakers. But the 2 JFETs class A preamp concept powered by a 9V battery and using input, output transformers and no negative feedback is promising as it can directly drive the Sennheiser hD-580 reference headphones to a good level direcly from a mic whispering signal. obvious remedy is to use larger studio quality input, output transformers, such as Jensen, Sowter, Aletc, etc. So some thought is given on how to fit all these on a small beautiful looking beige and brown colored Retex cosole box.

χαβουζα + αντιχαβουζα = 0

At your risk. This refers to adding 2 similar mics, one deliberately out of phase. Bass, mid heaviness is canceled. So is part of bad acoustics, noise. See previous posts. (For example 2 Shure SM59 microphones). What is best, this technique or using a Pleiades (175mH:175mH) bass correcting inline transformer followed by a Pleiades (130ohm,29Mh) mid correctking inline filter? Mics were used at 24in, about 30 degrees above head. Difficult to answer at this stage. Both tecniques sounded good and promising. The noise cancelling mic tecnique gave perhaps a more pro result as early reflections seem to be diminised. The mic filters gave nice timbre devoid of bass, mid heaviness ie a nice bright detailed sound too. A usefull experiment to decide would be perhaps better, ie studio acoustics or outdoors.

Michael Masser

A great man, songwriter and record producer. Interview on youtube: https://www.youtube.com/watch?v=E8HNg0Ex4rs

Bass correction filter is a better term to low cut filter for microphones. BCF, ΦΔΒ (φιλτρο διορθωσης βασης), φδβ

At your risk. This term was found in the book Microphones by BBC producer Alec Nisbet. In fact the proximity effect of directional microphones does not only emphasize bass but mid bass and mid frequencies too. This can be clearly seen on the Neumann Microphone manual by Bore, Peus. So it could even be caleed a bass, mid correction filter instead of a high pass filter. In fact the Pleiades gentle slope (130ohm,20mH) inline filter does this. It starts at a mid frequency dictated by an inductance of 20mH and gently deemphasizes as frequency is decreased, slope depending on the value of resistance R, for example 130 ohms. L is in series with R (in fact 2 R/2 on each side for balanced symmetry) and the total is connected across the output of the microphone ie in parallel. Yesterday Shure SM58 was recorded for a trial vocal. At 24in distance from head, above head say 30 degrees. Without any filter (due also too equal loudness curves, voice effort curves) sound appeared bass and mid heavy to listener's brain. (Monitoring is with celestion Ditton 150 driven by one transistor Pleiades 2N3053 power amplifier). Adding an inline Pleiades 175mH:175mH transformer decreased bass but mid still appearted emphasized. Adding one after the other the Pleiades (130ohm,20mH) removed mid heaviness but sound was lacking in body. Then leaving just the (130omh,20mH) bass, mid correction filter gave the best result. High frequencies would now come through in a sparkling way like Whitney Houston's 1st album on female and male voice which sounds fantastic, Is it recorded with Shure Sm7? Male voice on this experiment was singing one of the male voices on this album, recording to Sony TC-D5M which has a frequency respone up to 16KHz on type Ii cassette. Anyway, Shure SM59 sounds so far best with both filters cascaded. very nice treble definition, giving a smooth airy airy edge. But according to yesterday's experiments recording with the BeyerDynamic M260.80, at 24in, with both Pleiades filters gave the best result. Amazing detail smooth and sparkling edge to voice. Ribbon mics deserve this as the moving part is of so low mass, the ribbon itself which generates the EMF 9electromotive force), the voice voltage signal itself. From an extra thin conductive aluminum ribbon suspended inside a permenant magnetic field. As it vibrates by singing voice, electrons on it start vibrating too. As electrons now have velocity at every instant in time, each electron creates a magnetic field around it. Which varies at evey instant in time. This magnetic field interacts with the permenent magnetic field and each electron has a force and is pushed along the ribbon. This force varies at every instant in time. It is as if each electron is now dancing along with the acoustic music signal from the singer's voice. Electrons dancing up and down at the edges of the ribbon are the electric signal output which is sent to the voltage step up (impedance matching) transformer inside the mic. There must also be a damping effect on the electrons due to Lenz's law, so the so light electrons follow the singer's voice pretty accurately! Further reading: Feynmann Lectures in Physics Vol.2

Still don't know

On removing bass, mid frequency emphasis from microphones while recording a vocal part without using an external equalizer

At your risk. This could be on recording a sparkling vocal such as The Power of Love - Frankie Goes to Hollywood. Or pehaps lady lady - Georgio Morroder. A trick explained to me by Lefteris long time ago is to use a parametric EQ, increse dbs above 0, tune it to the voice fundamental or where the vocal sounds worse and then reduce a few dB from 0 until it sounds very nice. This may be mentioned in Wadhams book on recording, if memory is correct. But this post is about recording a nice voice without an EQ or even a Pleiades gentle slope low cut filter etc. The Lou Burroughs (ElectroVoice) trick described in his book microphones is used. 2 microphones, one deliberately out of phase, and singing to one of them. Their distance appart can be used as a parametric canceling EQ. It works on omnidirectional microphones, but will it work on cardiods for example too? Yes!, yesterday 2 shure SM59 (they have flat frequency responce) were tried. A special cable of 2 XLR inputs, 1 output (2 mics tonected therefore in parallel) but one of the female input XLRs is connected deliberatyely mistaken, out of phase. The sum was connected to Sony TC-D% PRO in mono mode used as a preamp. Monitoring in real time by Sennheiser HD-580 headphones. Mics were at about 24in, above head, pointing towards head while singing. If one mic is used we have the usual possibly proximity bass boost effect even at 24in, and the voice effort bass heaviness due to singing softly, (not loud), and the equal loudness bass boost effect from amplifying a voice. Plus room bass mode artifacts. If the second mic (the out of phase one) is connected, added) and the 2 mics are saqy 3 feet apart, some bass is reduced but there is still bass and mid exageration to listeners brain. If the distance of the 2 mics is reduced while singing at 24in on the 1st one, bass heaviness gradualy desapears, and then mid heaviness gradually desapears until at about 12in the vocal sound becomes crispy as on those classic recordings of amazing clear voice. There is no coincidence, 12in correspont to a certain wavelength which is turn corresponts to a certain cutoff frequency. You may experiment with mic to mic distance for a particular setup. It is like having a world class parametric EQ without the need of the equipment, just 2 mics and a special deliberatly wrongly made cable. Later addition, experiment retried. So far best sound is when 1 SM59 is pointing towards singer's head, 2nd SM59 pointing at some other direction, eg towards th piano. It is best to experiment.

A speaker secret possibly used on Amazon Alexa too

At your risk. A very helpful tip on building or making loudspeakers is that the box be much larger than the drive unit, or vice versa that the drive unit be much smallermuch than the box. This can give excellent no boomy and deep bass if the drive unit has a low reasonant frequency. For a closed box this reasonant frequency needs to be much lower than needed since when when the drive unit is mounted in the box the frequency will be raised by acoustic suspension. Anyway a 4.5in Fostex FE127E gives amazing bass on a bigger Pioneer box (see previous posts). And this Christmass present from my brother and his wife to our parents is an Alaxa, Amazon. Inside it is a tiny speaker. But the bass is surprisingly deep for Alexa's size. Do they also EQ?

Listening tests on a 1m by 1m 2 ply linoleum baffle.

At your risk. Baffle speaker is hung from ceiling from 2 poits using Picture Hanging Systems. A Grundig paper oval 5in by 10in, 5 ohms speaker is assymetrically mounted. It looks rather ugly. 2 ply linoleum glued by PVA is still soft, compliant. But this is peshaps why it absorbs vibration well. Sound is very clear, real and lively. It has this truthful quality of Hf heard near a record player stulys, although listening tests are done with CD. Speaker gives excess of mid and treble. So an inductor of say 0.7H is connected in series. A resistor (starting as a variable resistor) in parallel to inductor may be needed. Bass is nice. It could have been better as there seems to be a mid bass reasonance, (due to drive unit?). Would bass be more deep if more ply linoleum was used, but it would be very heavy. Perhaps using a say 50cm by 50cm would be more appropreate as on the Zeis Ikon baffle cabiet speaker. Barbara Streisand sounded very nice with speaker driven by the Pleiades single transistor 2N3053 power amplifier. Test is mono, actually only one cD channel is used. Since around New Year it had been desided to have only the Great Celestion Ditton 150 speakers in the small Pleiades control room. All other speaker tests are done on the much greater size living room. Still the Rola Celestion Ditton 150 speakers (in stereo) driven by 2 Pleiades 2N3053 power amplifiers in pure class A are prefared and this is the refference Pleiades reproducing setup. Aknowledgment to Mr. Yiannis for those beautiful souding speakers with so deep bass, fluid mid and extended balanced high frequency content. The amplifiers have small output transformers (see previous posts, after all power of amps is much less than 1 Watt. With the big Sowtewr SK05s output transformers although they are exxcellent and more efficient, bass on this particular setup may be much.

Brushing teeth with sea water

At your risk. This is not a medical advice. Just personal experience. Using now for a few years very good quality toothbrush Curaprox and Jordan. Firstly Curaprox is used, then Jordan which seems to be more helpful for inbetween teeth gaps. Using no toothpaste. Brushing after everymeal. Teeth are in quite good condition. When sea water was replaced by tap or filtered water, it was a disaster. Sea water seems to kill harmful microrganisms. This is possiblyt done by salt dyhydrating microbe cell membranes by ormosis. After brushing teeth, both toothbruses are rinsed in plenty of sea water. At your risk.

Happy New Year

Ευτυχισμενο Νεο Ετος