Grounding a low voltage DC preamp for a chipamp project...

[Stompin Tom]

Ok, so I've recently put together a chipamp poweramp using a LM4780 and this kit: http://audiosector.com/lm4780.shtml
I paralleled the chip (it's basically two LM3886 chips in one)... So it's in mono. I've gotten it up and running with no problems.

Now I'm going to experiment with various preamps to use this thing as a guitar amplifier. I was thinking of trying some of ROG's pseudo-amp pedals and probably run them at 12v+ DC with a wallwart for a little more head room. I'll adjust the gain on the poweramp to get enough volume out of it. I know there may be some issues with noise, etc., but that's part of why I want to experiment. I want to hear for myself...

So, my question about grounding is this: Say I'm using ROG's supreaux (http://www.runoffgroove.com/supreaux.html) and I want to put it in the same chasis as the power amp. The power amp is, of course, grounded... Do I just connect the supreaux's ground and the -9v supply to the star ground of the amp (also grounding the input jack)? Or do I have to somehow keep the AC poweramp and DC preamp grounds separate? I guess I'm ultimately confused by the -9v supply and ground being one in the same in the supreaux circuit... Seems if you tie the -9v and the power amp grounds together it wouldn't work or would hum like the dickens... I've tried to read everything I could on grounding, but I probably missed something. I'm no genius at this stuff... In any case, feel free to direct me to some helpful literature...