Quote:
Originally Posted by JAY X  Hi Tim!
I think by March i will end the summing mixer based on your drawings.
My question is if there are other options for volume control than stepped attenuators. ¿ maybe a dual ganged pot?
I suppose that the attenuator should go after the transformers. Or ¿can they go between the board an the trafos?.
I have the intention to put it as an insert in Cubase mix bus. 
Thank you for your help.
JAY X |
For gain you could put a pot between the 2 -ve inputs of the opamps to create gain. Less than x1 gain is how it is drawn. With a pot and limiting resistor between the opamp -ve inputs this becomes the traditional instrumentation input with the transfomer doing the summing/difference passively. Our Elixir mic preamp has the same design idea except it's only 1 input with a lot more gain, but still the siganal is re-balanced by the transformer..