[Help!] 4-channel volume control?

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Hi, I'm currently designing a general-purpose 4-channel power amplifier for stereo bi-amp, stereo bridged-amp or quadraphonic home systems based on Cordell Audio's "The Super Gainclone" design with 40W output per channel.
My current solutions for controlling volume on the 4 channel simultaneously are:

1. a quad-potentiometer
Problem(s): I can't get one locally and don't have a bank account to buy online.

2. 4x Voltage-controlled Attenuators with a single CV
Problem(s): Haven't found a low distortion VCA circuit and don't know how to design one.

3. Digital stepped attenuators: digital pot. ICs, Multiplying DAC Attenuator, discrete ladder.
Problem(s): for digital pot. ICs: I don't like working with surface-mount packages, for Multiplying DAC: need to program a microcontroller for log response and rotary encoder, for discrete resistor ladder: too much work and still needs a micro controller.

I'm currently considering the VCA method, can anyone help me with the circuit?
Any other solutions?

Thanks.
 
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Hi, I'm currently designing a general-purpose 4-channel power amplifier for stereo bi-amp, stereo bridged-amp or quadraphonic home systems based on Cordell Audio's "The Super Gainclone" design with 40W output per channel.
My current solutions for controlling volume on the 4 channel simultaneously are:

1. a quad-potentiometer
Problem(s): I can't get one locally and don't have a bank account to buy online.
2. 4x Voltage-controlled Attenuators with a single CV
Problem(s): Haven't found a low distortion VCA circuit and don't know how to design one.

3. Digital stepped attenuators: digital pot. ICs, Multiplying DAC Attenuator, discrete ladder.
Problem(s): for digital pot. ICs: I don't like working with surface-mount packages, for Multiplying DAC: need to program a microcontroller for log response and rotary encoder, for discrete resistor ladder: too much work and still needs a micro controller.

I'm currently considering the VCA method, can anyone help me with the circuit?
Any other solutions?

Thanks.

Just pay in cash a friend or someone that you know and trust that has an account/credit card and He can order it for you.;)
 
Sorry for bad english
I will try to gather all in one post.
Adjusts the tone, volume,
Remote control of RC 5
two inputs
memory installed in the OFF position

.
 

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Using a rotary encoder (the CUI ACZ16 (about $3)), a quadrature decoder IC (LFLS7184 by LSI/CSI (same price)) and 4 digital pots (Xicor X9134 or similar in dual or quad ($?)) will get you there cheaply! E

PS: Prof: Love the design (done that!), that is diy!, and the cat in the avatar!
 
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Status
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