My 7700 is on the bottom shelf of my two shelf high rack. I listened again last night. With my ear as close to the front of the amp as I could get, I could not hear any noise (hum or otherwise). I have 2 dedicated circuits but I don't remember exactly which way I plugged everything in. I think the subs are on one circuit (1000 watts rms each) and everything else is on the other. The satellite receiver and/or the PSP3 may be on the sub amp circuit - I don't think it matters for this discussion.

Definitely odd, as my 7500 is also silent, and I don't have it on a dedicated circuit. At least BloggingITGuy had a good option to fall back on...

Yep, I don't know if ATI has started to use lower quality transformers or has a bad batch or it was why these were B-Stock amps in the first place or what.

I really wanted to like the Outlaw more than the B&K, but was, in the end, unable to live with the "mechanical" noise produced by it.

Transformer noise can be a problem. I have two 2200 m-blocks and one of them hums when it gets warm but foutunatly it is not bad. My 7500 is dead quiet, knock on wood. One thing that aggravates the problem with the 7500/7700 amps is both transformers are located directly behind the front panel.
Too bad you had that problem because the 7500/7700 are great pieces of equipment.

butchgo, we have almost the exact system. Do you bi amp your mains or do you have separates for all your speakers? I am considering letting my pre/pro powering my rears and letting the 7500 power my outdoor speakers.

Well, now that I look again, not so much the same. Oh well.

I have my mains and center channel bi-wired.
The 2200's are driving the mains and the 7500 is driving the center channel and all of the surrounds. I have it set up this way so when I am listening to two channel music the 7500 is not being used. Can I ask why you would use the 7500 for outdoors speakers? It seems that an amp of this quality should be used for your home theater system and use a smaller less expensive amp for the outdoor speakers. I bought an Audio Source AMP100, 50W per channel, for my deck speakers but haven't hooked it up yet. This was like $90.00 with the shipping. I am going to use zone two for the deck.

Yeah, I have not decided on the outdoor speakers and the 7500. It is a long speaker run, so I had hoped the extra power would help. I do like the 7500 powering all of my speakers though...it too cold outside any way. Dont have to make that call yet. I would like to find a less expensive two channel amp, but I have not had alot of luck. Thanks for the info on what you use.

What sort of outdoor speakers are you using? There are some inexpensive stereo amplifier options around that might be a good fit for outdoor speakers if they aren't too difficult a load to drive or you don't want too high a volume.

Meat,
The AudioSource AMP 100 I got off of Amazon.com.
Parts Express also sells them.
http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=302-601
It's been to cold up here to mess with the outdoors speakers too.