Axiom Home Page Forums General Discussion Home Theater External Amps - Crown XLS1000 Class Amps

It really makes you wonder how they can do it? Just looking at the amp you provided the link to, you can't even buy an HT amp at any price that comes anywhere near that type of power yet alone for $500 bucks and its Class D configuration which is generally much more expensive and only 10 pounds!

I would love to have an experienced electronic engineering type who has expertise in this area offer an explanation for the BIG difference in price.

I think that audiopiles will tell you that Class D amplification isn't as creamy as Class AB. Or something.

The engineer would be as puzzled as you. You should probably talk to the marketing guy.

No, but these days, it seems they are.

The amp I have most recently seen bench tested was the new Peavey IPR 1600 and it plays clean. Fan noise when not playing program material was the only issue. Well, there were the screaming blue LEDs on the front panel, but electrical tape would take care of those nicely.

The Peavey is a solid amp.





To the OP here is a master list of pro amps that have been put on the bench.

http://www.avsforum.com/avs-vb/showthread.php?t=855865

1% distortion is pushing the limit of being audible and many of the 'pro' amps are spec'd out with higher distortion levels than this 1%. I have seen a few as high as 3% and a few more higher than that so you have to be careful and watch those little details.

most of the time, if one decreases the signal level by 1 dB or less, the distortion then decreases in dramatic fashion.
amps can produce 10% distortion easily by overdriving them.

when i was shopping for a proamp, this Crown XLS2500 amp was in my (very) short list. I opted to buy the QSC GX5 instead, mostly because of the price difference.

i totally agree with you, big and heavy and stylish costs huge amounts of money to produce, and audiophiles are ready to spend much more on distortion numbers that are 0.0001% less than the competition, or on class A amps that heat your house, or just on style.
check on the Musical Fidelity AMS100 amp, a huge 110 Watt/8 Ohm beast that's 1 meter deep and weighs around 100 kg. and, sitting idle, comsumes 1000 Watts; for the weight and size and price, it should put all other amps to shame sound wise.
on those kind of products, the marketing guys get a high fever.

what happens is, i think, that those pieces of equipment sell in so limited quantities that the prices must be very high to compensate.

it so happens that engineers know how to make excellent amps since the 70's, when Otala found the solution to TIM, and nobody can tell if one is better than the other in double blind tests.

I looked at the QSC as well, but the fact that they spec the power @ 1kHz (only) bothers me:

QSC power rating:

8 ohms / both channels driven / 1 kHz: 500 W

4 ohms / both channels driven / 1 kHz; 700 W

2 ohms / both channels driven / 1 kHz: 350 W


The Crown is rated for 440 WPC, both channels, 20Hz-20kHz, while the QSC is rated @ 500 watts at 1kHz. For all practical purposes, I'm sure they put out the same power.

But I'm bothered by the non-standard way QSC specs it out. It reminds me of the old days of hugely inflated power ratings in car audio because they weren't given in standard terms.

It doesn't mean the QSC is bad, I just don't like their deceitful (IMHO) marketing of the power.