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Old April 10th 05, 10:52 PM posted to uk.rec.audio
Arny Krueger
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Default 4 ohm watts and 8 ohm watts

Wally wrote:
Dave Plowman (News) wrote:

Maybe so, but how far downwards can the quality go, if they are to
get away with calling it a 'reference class studio monitor'?


'Reference' and 'studio' are often adspeak.


I can appreciate that, but they don't use those terms WRT to their
other amps, which are patently PA jobbies, the spec for the
lower-powered one being 260Wpc into 8 ohms, 0.1% THD, -100dB noise
20-20K, freq resp +/-1dB 20-20K, 3dB points at 5-50K. I think the
message between the lines is that the new one is better than the PA
ones.


The hidden agenda is that most PA amps have specs equal or better than
HiFi amps, if you back off their power ratings. IOW, take a 200 wpc
power amp with speced 1% THD, drop the power rating back to 160 wpc,
and watch the THD drop to 0.05% or better.

Case in point are my bench measurements on a QSC USA 400. At 130 wpc
it might have like 0.5% THD. Upon closer examination, the amp is
barely clipping. Back off the power output to say 100 wpc, the
clipping goes away, and the THD drops down to about 0.01%.