Anyone own the Yamaha A-S2000 - noob questions


Hey guys, I'm fairly new to hi-fi audio and purchased my first integrated amp a few weeks ago. So far i've been somewhat satisfied with A-S2000's build and sound quality but I have some concerns over a few things that doesn't seem quite normal with the amp.

The first "problem", is the phono preamp on the a-s2000. When I played one of my records, even at low volumes my woofers would flex in and out, I was worried that I might have hooked up the wires wrong or something of that nature but I double checked everything and even tested a different turntable. But what really had me disappointed was the overall sound quality of the phono preamp. My records sounded so dull and lifeless when testing it on this amp. I don't claim to have discreet hearing but even my family members could hear the difference when we compared each others amps/preamps. After reading so many good reviews and recommendations, I really expected this $2,500 integrated amp to be better than that... Considering that my cousin was just using a cheap numark mixer as his phono/preamp, I was a bit embarrassed when we compared... Is anyone else not happy with their a-s2000 phono preamp?

2nd issue, heat. I've read that yamaha's tend to get hot but this amp seems to be getting hot rather quickly. It's not unbearably to touch but it is enough to raise a concern. The heat is most intense around the rear right hand corner of the amp, this is where I believe the preamp circuit board is located. I know that class A amps are suppose to get hot but I can't find any information on what class this amp is considered to be under. Music is kept at moderate levels, NEVER passed 11 o clock on the volume dial. Are these amps suppose to get this hot?

3rd thing - and this one is probably normal - when flipping the power switch on my amp, I hear a 1 sec buzz/hum. What's funny is that the amp never made this noise when I initially used it. The only thing you would hear is the "click" sound, which I still do, but now it's accompanied by a buzz. Is this normal for amps?

Besides these setbacks, the a-s2000 does sound great and is powerful. Build quality would be be a perfect 10 if only they used metal switch levers instead of plastic. Fortunately, everything else is metal.

My setup:

Yamaha A-S2000
Playstation 1001
Pioneer PL-540 with audio technica cartridge
Vintage Kef C45 Speakers
Raw wires going to both the speaker and amp's end. *if it matters* Raw wires are hooked up to the top 2 binding post on the yamaha and raw wires are hooked up to the top 2 binding post on the speakers with jumpers, since i'm not bi-wiring.
astromoose
Something doesn't sound right. The only thing I would agree with is the amp does get warm, but never hot. I've never heard a buzz or hum when powered on and the phono preamp sounds very good in my opinion. Your kef's are fairly efficient at 90db, so 11 o'clock on the volume dial would be more than moderate volume unless your source has a very low output. I'm fairly certain the knobs and levers are metal, not plastic.

My only issue with this amp is the balanced inputs can only take a maximum signal of 2.8v.

I would contact Yamaha and make a warranty claim.
My runs rather cool to warm; about the same as Ayre AX7 what i use to have. The volume is at 9:00-10:00 o'clock with my Dynas X12 and REL R-305 sub. My, amp is absolutely quiet. Yes, definitely send it back, it might be a Bios problem. Johsti, 2.8V meaning +/- 1.4V, or +/- 2.8V? My concern was (still is) the sub high level hook-ups. I was told that it is OK to use +/- speakers terminals as a direct feed to my sub. My concern is that i would be shorting negative out from L and R channel, am i wrong?
Srmax - Did you replace Ayre with Yamaha? Can you please explain difference in sound?
I believe the balanced input was engineered to be used with Yamaha's matching cds2000 cd player which has an output of 2v according to the manual. I don't know what the maximum input level is for the as2000, but my PS Audio dac has an output level of 5.5v which is too much for it and causes audible distortion. Yamaha support has also confirmed that the as2000 can't accommodate 5v+ through the balanced inputs.

Other than that, I am very impressed with the performance of this amp.
It has been a year since I let my Ayre AX7 go. I haven’t done side by side comparison, sorry. The AS2000 is just a couple weeks old; I don’t want to misjudge its true potentials at this point. What is striking about this amp is the speed, the soundstage and space; back to front and left to right. I like it especially with more complex passages. It is the quietest integrated amp I’ve owned; absolutely quiet in the signal path and mechanically. Levers are plastic on mine, kind of disappointing.
1. Your speakers' cones flex in and out because the A-S2000 does not have a subsonic filter for the Phono input (which is usually omitted in current integrated amps nowadays :( ) This is also the case with all hi-end record players, phono preamps..etc. because these subsonic sound is engraved into the record's groove from the cutter head, and can only be fixed by installing a subsonic filter (like the KAB) between your record player and the phono preamp/phono input on your integrated.

2. You should check to see if you use correct phono cartridge for your turntable. Make sure you use MM cartridge for MM input, MC for MC input, and also make sure your phono cartridge's output voltage matches the range that your integrated can handle