You may want to give the Plinius SA-250 mk IV a listen. 500 watts into 4 ohm, Class A. I personally would go for a used pair of the Threshold SA12e monoblocks, they will also put out 500 Class A watts into 4 ohms. The best high power Class A amps period, IMHO.
Here is my favorite. Click on Gryphon Antileon Signature Monohttp://www.gryphon-audio.dk/indexmain.html
Be careful throwing around the "class A" terminology as nearly all amps that flaunt Class A status are only so for the first tens of Watts (even a hundred is rare), not for the full 500W or what. A 500W class A output would burn up 2500 to 3000W which is a tough thermal challenge. Generally class A refers to the fact that the BIAS is class A, and not operation at full power. Actually nearly all audio amps could be called class A amps. It is just that the class A upper limit changes making some more class A than others (e.g., some go AB at 50mW and some at 50W).
I also meant to add that the new Pass XA series is surely worth looking into (and the other Pass for that matter). Arthur
Pettyfeversk: Your Dynaudio's will take a million watts if you can feed it to them. So long as you keep the quality level of the power that they are being fed up to a high level, the more power that you can feed them, the better they will sound. Welcome to the world of "phenomenally thirsty" speakers. My guess is that about 800 - 1200 wpc should do it. Obviously, this will depend on the size of the listening room, type of music and the spl's that you want to achieve with good clarity.
John: I like your thinking. I too "love" the SA12's. I had a chance to buy a pair a while back for a very fair price and passed it up. I am kicking myself on a regular basis over this one. Out of all of the deals that i've passed up, this is the one that haunts me. Having said that, I'd like to see how the 12's stack up to the newer X amps in a side by side. Regardless of which one would "win", it would be quite fun and interesting to say the least : )
Art: Your right on the money. I wonder what amp is actually biased and operates in Class A the longest ( highest power ) ??? Bare in mind that as you drop impedance, your ability to remain in Class A also drops. I know that Bear's amp, which is a MONSTER ( or is it a "bear" : ) in terms of sheer weight, runs in pure Class A up to 50 watts. Anybody know of anything that beats that ? I know that a lot of amps say "Class A", but i sincerely doubt that they operate up to the levels claimed in Class A. Sean
Check out Edge and Boulder, as well. These also offer a variable bias approach, somewhat akin to Krell, but implemented differently if I'm not mistaken. Class A operation is maintained by ensuring the bias point is high enough relative to the signal level to prevent signal distortion or class AB operation. This greatly improves amplifier efficiency, but at what sonic cost? None? A little? A lot? Listen for yourself and decide. Good luck.
As above, regarding "clas A" & how much of it we really get.
Other than Bear's Symphony1, another amp that runs in A for a long time is the Symphonic Line Kraft 250 (stereo & monos: the latter offer ~250 A instantaneous @ peaks). BUT, like Bear's amp, they are huge and heavy (+150pds each), and UNLIKE Bear's amp, they are ugly. But they produce prodigious bass and natural harmonics in the upper end...
Why am I missing the 'older' Levinson gear here?
IMHO, the 20.6s still rock ....
You might also consider the sunfire amps, not exactly class A but what the hell. I have heard nothing but good things about Pass, but I have heard some krell KSA's and they are amazing. Also though not class A, what about the big Bryston amps 7Bsst? A great amp and more affordable also reliable! Since you are asking about class A amps have you experinced the Heat generated by true class A devices? It is something to consider. On the nelson pass website he claims something like for a true class A device you should expect an amp to weigh something like 2 pound for every watt of power that is very heavy and I know of two people granted they are in thier 50's that have damaged thier backs moving large amps(no joke!). Good luck!
I run a krell Ksa250 0n my large power hungry speakers. jffyg is right on the money regarding weight and heat of class a high power amps. My amp is 150 lbs. and runs very warm to the touch. My book states that it can put out 2000 watts into 1 ohm load. I think that ware all these big super power amps really shine on large power hungry speakers is at low volume listening. They sound just as good at two or three watts as they do at hundreds of watts.
try krell krs100or krs200 ,or lamm m1.1, they are pure
class A all the way and sound awsome.
I've owned Dynaudio Contour 3.3 speakers for about three years now and have used both the Plinius SA 250 MK.IV and now use Pass Labs X600 reference monoblocks. Both amps had no problem delivering enough power to make the Dyn's sing. However, they are very different sounding amps. The Plinius being warmer (does not sound as "solid state" as most SS amps) and having a more natural sound. The Pass being very revealing of the source as it retrieves every bit øf detail, which is not kind to poorly recorded music. If possible, try to demo the amp in your home before making the purchase. Your preference in the type of sound you enjoy, can only be determined by you! Some audiophiles hate Krells, some Krell owners hate Plinius, some Plinius owners hate Pass Labs, and we all hate Bose.
"Music is in the ear of the beholder!"
Good one Rosstaman, and I've heard the same story all turned around. The fellow I bought my X-600 to power the Apogee Scintilla from also was selling his Rowlands 9tc. He preferred the Pass amps over the Rowlands. I'm using the 600 to power the only 1 ohm speaker there is. There just isn't any more power hungry speaker around than the Scintilla. When this speaker was made, no amp could make it go loud. My Scintillas go real loud, and just like you said, the Pass shows every tiny faintest detail in your recording AND your audio chain. I don't miss the warm (natural?) sound of the Plinius, as I am employing a CDP with a tube output. I control sound nuances with tube rolling. That way I get to keep all the big dynamics and transparency of the Pass.
Plenty used Pass amps X-250 & X-350 here to buy. They sound wonderfull to me.
The new Parasound JC-1 is happy driving 4r loads and is rated at 800w into this load, but it does well in excess of a kilowatt.....There will be reviews out shortly.....
Solid State ... Krell, Classe' Mark Levenson.
or Tube... Audio Research, VTL , Conrad Johnson, Sonic Frontiers