Hi there, i have no clues about PSRR to start about, i was trying some caps here and there but it didnt help. What i do to see PSRR in spice is in spite of putting a DC source (48v) i put a sine source with the same dc offset and something like 50mv 30Khz singnal. The LTP seems to amplify the noise in the same way it amplifies signal, and we are talking about 58dB in sim. I think it could be even more with some matched bc560c, or other higher hfe device. The general idea is to make a mic preamp that can give u +4dBu from mic in as minimalist as posible. At the momment i got about +15dBu from a 10mv signal and about -10dBv from a 1mv signal. So i could simply add an attenuator not to clip power amp if the mic is too sensitive, but the PSRR is awfull! Any thoughts?
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i think this one has better PSRR, but not sure since i skipped the polarization resistors... But i`ve got 62dB gain, which is the maximun without clipping in the balancer, since i end up with 22Vpk per signal when input is 10mV. Only thing that bothers me is that idk about real world, and the balancer only loads one of the sides, varying by 2% one of the current mirror currents (not the LTP ones tho). (would be nice to be under 10ma), any suggestions?
