Pro Audio Design Forum

mediatechnology wrote:when did the dbx 2150 VCA get introduced

Speaking of dbx VCAs, I have an old dBx 163 circuit where the VCA was done in discrete components.
It used 2 dual transistors. 2SA798 & 2SC1583
Any interest in seeing the circuit?

JR: I'd be interested in seeing the "cool stuff".

Cheers
Ian DuRieu

emrr wrote:Nice compilation. Here are some corrections:

Thanks for the corrections.
The PDF file at http://leonaudio.biz/AES/Aug-15-2006/ae ... ug_15f.pdf has been updated.

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Hi JR, Passing the common mode through to the output doesn't really strike me as a benefit. It sounds like you may have only seen figure 4 as posted by others. This is only the input stage. Please see Figure 1 on page 2 of the PDF file for the full circuit which includes a pair of 4 resistor diff am...