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

Imagination Produces Reality

Microphone Array Recording

MAR.


Many microphones connected together in a similar way to many speakers forming an array. Each microphone may be near one source or different sources of sound. No adding (mixing) console is needed.


Explained in the next euroelectron posts.

Sewer Pipes greatly improve the reverb quality of echo chambers

Drain or sewer pipes seem to be used to diffuse sound in echo chambers. They may absorb low frequencies too as they can sympathetically vibrate and dissipate the incident acoustical energy.


They can be seen at Number two echo chamber at Abbey Road studios. They are thick and from floor to ceiling.


They can also be seen at echo chambers used by the BBC's north region.





References:


Abbey Road - Brian Southall - Patrik Stevens Ltd - copyright EMI records Ltd 1982 - page 193


Audio and Acoustics - G.A. Briggs - Wharfedale Wireless Works Ltd - First edition 1963 - page 65

Removing low frequency rumble with omnidirectional microphones

This happened by accident.


2 Beyer M55 were connected in series before feeding the preamplifier input.


They happened to be out of phase.


This canceled low frequencies from far sources. Explanation seems to be the large wavelength of low frequencies.


Also most of the ugly bass reverberation of a room disappeared.


Note:(Is it correct assuming that outdoor sounds from very far would be almost completely canceled as the arrive practically at the same time to both mics. So when recording direct to mono or stereo with microphone arrays a good trick may be to arrange some of the mics to be out of phase. It should be easily done while physically connecting the cable outputs of microphones together in parallel series combinations as described on the following euroelectron posts).


And while close micing with them each source had full natural body.


This trick may prove useful in direct recording to mono or stereo using many microphones, their outputs connected in series-parallel combinations.


Signal path:


M55 in series with (-M55) - Canford input step up transformer - Pleiades V4, 3.4V battery - Realistic disco mixer at mono mic in - Sennheiser HD580


More on this Pleiades connection on the following euroelectron posts.

Recording superbly direct to mono or stereo

Some of the best recordings in our planet were done directly to mono or stereo.


Years ago I thought this only meant one microphone or 2 microphones only.


Not nessasarily so.


While Blumlein pairs or binaural pairs can be superb, on pop music and not only it is best to have the mic as close as 3-4in to the source. It can be less it can be more but not 3ft. As Frank Laico says you can't get a bass sound that way.


So every instrument is near its microphone. An obvious example is Take Five - Dave Brubeck recorded at CBS 30th street church in New York.


It is possible to combine the signal from more than one microphone without the need of a mixing (adding is the correct word in electronic engineering) console or desk.


Many microphones can be directly connected to each other in series or parallel combinations. And the sound can be superb as it is possibly the most simple signal path on earth.


He would a full orchestra sound recorded this way. The signal from many microphones connected together can be so strong that a preamplifier may not be needed. Each musician does not need to play loud as there is a microphone next to him-her.


It is simple inexpensive as only microphones are needed. And a parallel series combination of many microphones can make again a resultant equivalent mic of 200ohms or 600ohms or anything desired to even connect directly to a analog to digital converted or a analog tape recorder.


More on examples of connections on the following euroelectron post.


Reference:


Anatomy of a session - Frank Laico - AES


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

Connecting 2 or more Beyer M55 microphones

At your own risk.


2 equal resistors in series make a resultant resistor of double resistance.


2 equal resistors in parallel make a resultant resistor of half resistance.


The same applies to loads like loudspeakers and to generators like microphones!!!


A Beyer M55 (500Ω) was connected by accident in series with an AKG M 201 -100 (800Ω unbalanced). The sound of both mics was superb. Many microphones can be used for just one voice making effectively a mic of very large diaphragm with the transient responce of a small diaphragm. Same idea as on Pleiades speakers. This may be called the Pleiades microphone. Of coerce many instruments can be recorded, one with its mic, mics, without the need of an adding (mixing) console. No power consumption, economy, and possibly the simplest signal path.


Setup:


M55 in series with M201 - Canford stepup input transformer - Pleiades V4, Vb=3.4V - Realistic disco mixer mono mic input - Sennheiser HD580


Then 2 Beyer M55 were connected in series one of them was unbalanced.


The sound was superb and of course one can sing in front of both mics for double voltage output. Does this mean 4x power?, as the input impedance of a preamplifier is usually high. This means the voltage will be doubled with no voltage drop. And from basic physics P=V*V/R where P is power, V is voltage and R can be considered further to be the load at the output of the preamplifier. Double voltage at same feeding preamp load impedance is 4x of power.


2 microphones can be connected as follows. They do not nessasarily need to be balanced but on the following balanced microphones are assumed.


Each mic has its XLR out. Pin 2 of course is live and pin 3 is return.


On the above example alligator short cables were connected from pin 2 of one mic to pin 3 of the other mic. The pins 2 and 3 left out is the new resultant output.


4 Beyer M55 or other microphones can be connected in series parallel combination to get back to, an impedance that is same as of a single mic. But this mic has now 4 feeds.


Assuming each mic is 500Ω. Two mics make a 1KΩ combination. The other 2 a 1ΚΩ combination. And the 2 combinations connected in parallel takes us back to 500Ω.


Same reasoning applies to 200Ω microphones or microphones of any impedance.


Any combination is possible.


If one needs less sensitive and at the same time some more sensitive mics... Then one can find that the 200Ω mics would sound less than if they were 600 Ω. So any impedance combinations desired can be connected together.


Many microphones can be connected in series to give a very large voltage output that can then feed if needed the grid of an electron tube or gate of a JFET just as is done inside a Neumann U47, preamplifier using a VF14 underheated tube.


How would a full orchestra sound recorded this way?


Is this the simplest possible signal path to record many instruments with each mic close to the instrument?


Each musician would not need to play loud so the sound should be superb.


Each mic can be hang from ceiling or from trees if outdoor acoustics with full absorption is needed.