Sharing LR Bypass Gain Capacitor possible? (CE Amplifier)

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abbey road d enfer

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, the full diagram of each amp goes attached here and you are welcome to comment on it.
This schemo does not make much sense.
The potentiometer swings from an in-phase signal to an out-of-phase signal.

I wonder how you came to this gain structure.
What overall gain are you targetting? Including the elusive headphone amp's gain?
What acoustic level? what capsule sensitivity?
Anyway, your global gain switching doesn't work; you need a 3PDT switch.
 

domingo

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This schemo does not make much sense.
The potentiometer swings from an in-phase signal to an out-of-phase signal.

I wonder how you came to this gain structure.
What overall gain are you targetting? Including the elusive headphone amp's gain?
What acoustic level? what capsule sensitivity?
Anyway, your global gain switching doesn't work; you need a 3PDT switch.

I have to be honest on that I'm only doing my best here, despite my ignorance and respect to those who have real knowledge.

The idea of the (volume) potentiometer is to cancel the signal rather than dropping it to ground. It was an experiment based on the idea of negative feedback... and in practice it worked, compared to a normal volume configuration the signal swamps down very silently. It also had the advantage of leaving the first amplification stage untouched by any pot. Might be that I'm doing something horrendous here anyways and I'm not certain of how it actually works.

My target is an ADC (SGTL5000, 29K input impedance) and a parallel CMoy HP opamp (AD8620 based).

Capsule sensitivity is -24dB (AOM-5024L-HD-R).
 

Bo Deadly

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Capsule sensitivity is -24dB (AOM-5024L-HD-R).

That's an impressive device. I would try one of these in a studio environment.

This makes an SM57 look like a child's toy. What's the max SPL of an SM57?

There's probably a clever circuit that could use two to make a decent non-onmi mic.

Definitely gonna need a bass-cut right at the front door though.
 

abbey road d enfer

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The idea of the (volume) potentiometer is to cancel the signal rather than dropping it to ground. It was an experiment based on the idea of negative feedback... and in practice it worked, compared to a normal volume configuration the signal swamps down very silently.
I don't understand that. A volume potentiometer also drops the volume silently (for what it means...).
It also had the advantage of leaving the first amplification stage untouched by any pot.
Really? As far as I can see, the pot "touches" both the first and second stage.
Might be that I'm doing something horrendous here anyways and I'm not certain of how it actually works.
It's not horrendous. It just does not make sense.
My target is an ADC (SGTL5000, 29K input impedance) and a parallel CMoy HP opamp (AD8620 based).
What is the sensitivity of the ADC and gain of the HP amp?
Capsule sensitivity is -24dB (AOM-5024L-HD-R).
OK, what spl are you trying to record/listen to?
 

DKatz

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In the attachment goes what I have in mind... I interpret from the answers that this would add crosstalk, but why would that be the case? If the 0V to all PAs is common in any case...

PD: A SPDT is drawn because LibrePCB comes without SPST switches.

PD2: Should the ground of the "Gain Cap" better go to the emitter resistor 0V or the electret GND?
Each 2 channels becomes a differential amp.
Cap to electret GND.
 

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