Since I published my balanced circuits, there are a couple of new op-amps available that make this task both simple and far more accurate than just using 1% metal film resistors (BTW, if you look inside a Rane box, the first thing they do is to convert to unbalanced using op-amps). This new solution uses a pair of audio line drivers (DRV134
) to convert to balanced and a single line receiver (INA2137
) to go balanced to unbalanced. All the needed resistors are on the chip and laser trimmed for accuracy. I have put balanced outputs on both a C-11 and a C-2 using the DRV134 chips with great success, and am working on a balanced input for an M-500 using the INA2137.
It should sound like it isn't there!
There is a difference between hearing and listening...
Making life enjoyable through expensive electronics.
Carver: C-4000 & C-1 preamps, PSC-60 preamp/tuner, TX-11a tuner, M-400 (2), C-500, M-500, M-500t, M-500t Mk.II, A-500x, AL-III loudspeakers (2 pr.)
Sunfire:Theater Grand III processor, Ultimate Receiver, Cinema Grand Signature 400 ~ seven, True Subwoofer Mk. II, D-10 Subwoofer