recently we did some small poweramp testing for my friends secondary rig. Original idea was to test Crown XLS Drivecore 1500, so we asked our another friend, who is local Crown dealer. When we picked up this amp in his store, we've also got used Yamaha P3500S with recommendation from him. Next amp for comparison was power section of GB Shuttle Max 12, which is my friend's main amp (he loves it, main motivation for purchasing of another amp is backup and possibility to try ahother preamp flavours with separate power amp).
All amps incl. Shuttle Max have similar power rating per channel - ranges are 300-350W/8ohm and around 525-600W/4ohm. Briging or 2ohm operation are not necessary for friend, because he already accomodated all his cabs for running with Shuttle Max (4ohms min, two cabs on separate channels) and he's pretty happy with volume levels achieved by its Shuttle Max.
We run amps to different cabs (GB Uber 212, EBS Neolines.. some combinations), preamp was Focusrite Tone Factory (versatile pre with lots of clean headroom). HiPass Filtering was disabled on all amps, for most test I applied HiPass filter on preamp (set to cca 30Hz second order), which worked pretty good for removing unnecessary rumble from speakers without affecting tone. I tried to always gain match amps by ear between tests.
We both liked Shuttle Max power section - sounds detailed and preserved great articulation on all levels, near clip (loud as heck) it started to smooth transients with limiting, but without loosing overall balance.
Yamaha sounds best to our taste - same detailed sound and articulation as Shuttle Max, but with even more transient headroom.. Greatest difference was at lows, fundamentals seems to be presented with much longer decay.. I was expecting some marginal differences, but you can really hear it and feel it during playing.
Crown was big dissapointment for us - it hadn't neither midrange clarity nor authoritative lows of Yamaha (bass presentation was roughly same like Shuttle Max). Overall, sound was bit flat and processed (sorry for lack of better word).. Harmonics seems to be quite congested in comparison to both previous amps. When I put amp to bridge mode, it doesn't help with described characteristic, although we've obviously got more headroom.
So that was our conclusions.. Crown didn't pass (unfortunatelly, because it has big advantage in weitght and depth) and friend is buying this Yamaha. And from my point of view it's great sounding amp at given requirements.. Also price/value ratio seems to be great for me (cca 400EUR here).
It could be interesting alternative for anyone looking for solid and good sounding poweramp.
Here are some description and tech. stuff of P3500S
+ amp feels very solid (good chassis, stepped pots, connectors, temperature)
+ very quiet fan
+ variable HP and LP filters directly accessible from backplate (sec. order 12dB/oct).. HP goes from 25Hz
+ some preset (probably just EQ) called YS processing (although designed for small Yamaha PA speakers, it sound pretty nice with 1x12 EBS box - dehonking of midrange a evening bass response)
+/- lower model from P series range by Yamaha with "classical" PS with toroid transformer (5000 and 7000 uses SMPS), so it has 15kg (for someone it could be to much, although one of lightest amp with similar rating and type of PS.. it's debatable about influence of transformer to sound quality within range
- bridging is officially supported to min. 8ohms (4ohms will works, but i expect that, it'll affects longevity and reliability of amp)
For sure I couldn't comment reliability, but I've got one positive message about it, on folk told me, that he put several these Yamahas to pubs, where he expect, that everyone is DJ up to protection LED and people are pouring beer to audio devices.. :-) So far he has no repair from 2005.
RMS power rating:
1kHz, THD+N=1% 8 Ohms Stereo: 390W + 390W
1kHz, THD+N=1% 4 Ohms Stereo: 590W + 590W
1kHz, THD+N=1% 8 Ohms Bridge: 1180W
20Hz-20kHz, THD+N=1% 8 Ohms Stereo: 350W + 350W
20Hz-20kHz, THD+N=1% 4 Ohms Stereo: 450W + 450W
20Hz-20kHz, THD+N=1% 8 Ohms Bridge: 900W
Short term power:
1kHz, 20mS nonclip 2 Ohms Stereo: 1000W + 1000W
1kHz, 20mS nonclip 4 Ohms Bridge: 2000W
Here is inside photo from japanese page: http://www.comeon.jp/shop/pa/images/...3500s_open.jpg
Have a nice Chrismas!