active crossover power supply pcb check before making

[Sheldon]

Thanks for the reply AndrewT. I'm still working on the new pcb, I'm putting ceramics right on the input and output.

For the muting relays, they are supposed to ground the output when the relays stop recieving power, so I would want to guarantee the normally open has contacted before the power has fully dropped. I think that would require a minimum power level threshold. The opposite way, mute when power is applied doesn't seem as robust.

You can "tune" it pretty easy to work both ways, i.e., relay closed with power off. Relay delays opening until power has reached full voltage for a bit. Relay closes before power drops completely. This is pretty easy to do if you drive the relay from before the regs and have 10 so extra volts to play with above the reg. I've done this on a chip amp. It would be nice if you could just compute it, but that's not required. You just have to play with RC values in the relay circuit. Add resistance in series with the relay until it just activates. Back off the resistance some and start adding capacitance to ground until you get the delay you want. The turn on delay will be longer than the turn off delay, due to the charge/discharge rate of the cap.

Sheldon