Threshold S/5000e new amp too good to be true???

Thanks for the link. The 250 wpc rating of the 38 lb. S/5000e had me digging out my original E Series operating manual. The early 90's vintage S/550e was also rated 250 wpc, yet weighs 97 lbs. The 250 wpc Pass X250 weighs 100 lbs. Makes one wonder how these contenders stack up on the test bench.

Maybe it gets so hot because the case is light and doesn't offer much in the way of heat sinks. A well constructed case can add a lot to the weight. If the weight comes out because the transformer is small, that's a different story -- they never did say that it's 250 wpc RMS ;-) The Bryston 4B-SST is rated at 300 wpc and comes in at 50 lbs. I know that's an honest rating and it doesn't run hot so I would guess that much of the weight save is in the case construction. In any case, I guess it handles tough loads and sounds great per one reviewer. It would certainly be something worth considering for the money.

It's possible that the Threshold runs hot because of a high class-A bias. having said that, then *maybe* it should have larger heat sinks. Theshold has a history of producing class-a amps.

The Bryston has a relatively low class-A bias (less than one watt?) so it's not going to run too hot, even with smaller heat sinks.

Good points Loudandclear. Still ... the weight difference makes you wonder. Certainly class A runs hotter, but 250 wpc in class A would require a pretty hefty power supply, wouldn't it? At minimum, as you stated, it should require even more in heat sinks. Like Rockvirgo, I'm still scratching my head about the weight.

Ozfly,

I checked with Threshold and the S5000/e has 45 watts per channel of Class-A before it switches to Class-B.

45wpc of class-A is very high bias for most class A/B amps.
That's why it runs so HOT.
You gotta wonder if there is enough heat sinking there.

Anyone have a listen to this amplifier yet?

*bump*

Someone must have heard thsi amp by now. No?

I recently installed a Threshold S/5000e in my system, and I can only comment that the Soundstage review was quite accurate. It's a superb amp, especially for the money (currently $3000). The previous forum comments about it running too hot are incorrect in my estimation. It just runs "very warm" - i. e. you can hold your hand on it indefinitely without getting uncomfortable.