I've got a mic point, XLR, at some venue. I want to run my notebook's audio out into it, but connecting ground and audio into the point directly results in the audio being minimally above the noise floor. This, I suspect, is because the notebook's audio cannot source enough current to bring the output signal levels to above the noise floor.
I've attempted to use a pair of opamps, one in inverting and the other in a non-inverting configuration, to basically build a DI box. The quick veroboard prototype with LM741s work, but that was with a separate power source. I want to run the box off phantom power, saving me the need to carry along replacement batteries.
Attached is my initial design, which I suspect may have some kind of problem, as potentially 24V may be feeding back into the opamps when the cap is discharging the other way. I'm asking for another set of eyes to scan that and find any further problems, before I go etch a board.
And before anyone mentions it, yes, I'm perfectly happy with the performance of the 741 in this application, and I do not happen to have alternate parts sitting around.