On Thu, 23 Sep 2004 17:11:22 -0500, David Maynard
wrote:


Terran Melconian wrote:


....
...
I expect that the power ratings for the individual voltage outputs were
spec'ed in the same dishonest way that hifi manufacturers used to rate power
amps (still do, in fact). Each *individual* output would supply the
specified current or wattage; but load them all up at the same time and POW!

Well, an audio amp shouldn't 'pow'. What should happen with a single
channel power spec is you run into distortion before you reach what you
'think', from the channel spec, is max power output. (spec'ing single
channel power is done to cover the power supply's inability to provide that
much power to both channels simultaneously. Voltage output droops and
causes distortion)


Amp manufacturers used to spec their output power one channel at a time, for
a *very* short time (even down to milliseconds). They could 'honestly'
state an inflated value, but real-world ratings were considerably less.

Well, I don't think whether it's both channels driven or the bogus 'peak
music power' really fall into the same category. A single channel spec does
have some sense to it. 'Peak Music Power' doesn't.

But, for a completely 'honest' number one should be looking to continuous
RMS output, both channels driven.


I seem to remember there was a "peak music power" test or some such
thing where they did actually run a power amp circuit for some
fraction of a second before it vaporized and claimed the measured
output as the spec of the amp.

After that nonsense, they got into honest specs for awhile. RMS output
measured with both channels driven into 8 ohms, across 20hz-20khz
bandwidth.

Then all that went away and all you see now is these silly X.1 channel
entertainment boxes.

Personally, I like to spin the amp around and read the UL wattage
label on the back of the unit.

100watts per channel 5.1 with a 230watt UL sticker