Yes I know...there is that other project I should finish....
However, I could not resist to post something which came to my mind after mulling again over Pedja's AD844 I/V, and also that "Supersymmetric" circuit Nelson Pass proposed with these so-called Current Feedback Op Amps.
Attached, on the top you find one channel of a very simple circuit, which could be used as a preamp.
To reduce the gain of the amp, in order to be able to run it open loop, a resistor must load pin 5, the TZ-node of the AD844. So I had the idea to use the volume potentiometer to accomplish this. And this way, the pot is "isolated" from the input as well as from the output.
The output buffer of AD844 is quite beefy and should drive even longer cables without problems. Max. output current is ?50mA.
And this diamond buffer runs open loop....do you read this, Jocko?
On the bottom, the same circuit, but in a balanced version.
Staying with the philosophy of such an amp, an open loop voltage regulator should be used, however they have a highish output resistance. This balanced version would be less demanding, as the supply current fluctuations of both amps will cancel each other (more or less).
A quad volume potentiometer would be needed in such balanced pre, or a nice relay volume control.
What do you think?
Would it be worth to buy some of these not so cheap AD844's? (as I have still to buy some parts for that other