General Asylum: REVIEW: Onkyo M-504 Amplifier (SS) by Jim P.

I purchased this amp to add to my Yamaha RX-V2095 because I want to be able to run low impedance speakers at higher levels without damaging my receiver. Currently I'm using a pair of Paradigms for the mains. My next purchase is going to be a pair of MMG's. The amp surprised me last night when listening to Pink Floyd. I heard some footsteps that were previously obscured. The thing weighs a little more than my receiver which is supposed to be a flagship model. It(the Onkyo),weighs 22.5 kg(49.5 lbs). I'm going to have to buy another equiptment stand or just build one myself with all thread and shelves from home depot. One quirk with the amp is the speaker connectors. They look like 5 ways upon brief inspection but accept only bare wire, no bananas or spades. :( I got around this by using a set of Pheonix Gold connectors that attached easily to my MIT icon ends. I'm getting better soundstage now and believe this is due to the Dual Mono design(?). Without getting into a bunch of "audiophile terms", this amp sounds very good to me! Good detail and soundstage and looks stunning to boot! There are three very large transformers inside. For those interested they are not of a toroidal design but very large nonetheless. The sound is very smooth and enjoyable to listen too. The heatsinks are healthy looking aluminum fins that are robust. The M-504 doesn't get very warm although it will run at around 100 with my digital temp guage on top which is comparable to my Yamaha. This amp is harder to find now that they are discontinued last month(been in production from the 80's!) Home theater is killing 2 channel audio n some ways. I think the Yamaha 2095 will serve as an excellent pre/pro which would be hard to beat without spending high end money! I eventually want to get 2 more amps to complete the H/T side while concentrating on 2 channel music. H/T is nice but I still like plain ol stereo! The amp puts out 165 watts into 8 ohms 20-20. I don't know about the 4 ohm rms,(I would like to know if anyone does) output but the beast seems to have a lot of headroom. Does anyone know of tweaks for this critter? Here's the specs for those that care.
Power Output - 2 x 165 Watts

Dynamic Power
2 ohms - 530 W/ch
4 ohms - 350 W/ch
8 ohms - 210 W/ch

THD - 0.003%

IM Distortion Rated Power - 0.003%

Damping Factor - 140

Frequency Response - 1Hz - 100 kHz (+0, -1.5 dB) VERY WIDE dynamic range!

Signal-to-Noise Ratio - 120 dB (IHF A)

Dimensions (W x H x D)
Inches - 17-1/8" x 7-1/4" x 16-5/8"

REVIEW: Onkyo M-504 Amplifier (SS) Review by Jim P. at Audio Asylum