hello,
is it ok to wire two sets of preamp outs on a preamp in parralell? (so that one can go to the main amp, and one to a sub)
If so, how would you wire this?? tia
No.
Each amp sees virtually the same signal as if it were connected directly (without the y). This is because the input impedance of the amps is much higher (10Kohms to 100Kohms) than the output impedance of the preamp (less than 100 ohms).
Basically the amplifiers see the same output voltage,
but the preamplifier has more output loading, it needs
to provide the current to drive both amplifiers.