Solid State Relays used for DC

In my application (building a GainClone) I'm going to be turning the amp on and off by switching the +/-Vdc supplies with two relays - one for +Vcc, one for -Vcc, ground will remain connected. The relays will be placed after the transformer/psu and before the amp modules they power. I would simply switch the primary of the transformer except for the fact that the transformer will also be powering the control circuit. Until now I've been planning on using a couple mechanical relays that are rated for this kind of DC load, but they each pull up to 200ma and that would be asking a lot of the little TREAD I'm planning on using for the 5V supplying the relays, microcontrollers, and eventually LCDuino system.

I'm looking on Mouser and the the number of SSRs that specifically state ratings for DC load is slim, and they're all either low on stock or of an unsuitable form factor. I'm wondering if AC units with high ratings (such as 120Vac @ 10A+) would be suitable for switching ~35Vdc @ ~3A - does anyone have experience with this?

Yes, I wasn't sure either. I asked a question about a month back about whether it was prudent to switch the secondaries or to switch the DC supply after the PSU and there wasn't much consensus. To me it makes more sense to switch the DC, so that the PSU is always on and thus always presents at least some load to the transformer. It can't be much different than how I am testing the PSU now (just the PSU, no load on it other than the resistors across the caps and the LED) which seems fine. Is there any problem with doing it that way?

Ah, so it's more a problem of surge current when the amp is flipped on if the PSU already was on, rather than having the amp come up a little more slowly with the PSU?

Would it be preferable to switch the secondaries before the PSU, so the PSU and amp powered up together?

Yes, the TREAD is running off of another set of secondaries on the single transformer (hence why I can't just switch the primary on and off). I could use a second transformer exclusively for the TREAD 5V supply but this transformer is shielded (building everything in a single case) and I don't want to waste the space and money on another small shielded transformer, if possible.

I guess I'll give it a shot in my test setup and see how it goes.

Double post