[eezip]

Actually Howdy, there are people out there [here] with actual electrical
design experience who's opinions are based off of actual measurements
and experience and can speaker authoritatively about the benefits of
caps. Online, it is hard to determine who really knows their stuff.

If I might add mine into the mix: Audio has very high crest factors.
This means that while peak power output is high, average [RMS] output
power is about 1/8 peak power for full range and up to 1/3 peak power
for bass or other signals which can be audibly tolerated at moderate
clipping levels. The crest factor also varies with the type of music.
This means that while the peak power is fixed by the rail voltage, the
long term output power is determined by the rail capacitance and the
power supply [because the power supply topology determines at what rate
the rail is replenished]. Real world music signals do not contain enough
continuous signal to pull the rail voltage from idle very much. So, if a
manufacturer quotes a RMS power output, and it's valid, you will see
more power than that rating being delivered to your speakers with music
signals. What it all comes down to is that only highly compressed, low
frequency music signals or test signals contain enough continuous
information to make external capacitors have any effect. Besides, the
power ratings the amplifier manufacturer gives are with the internal
capacitance and adding more to that won't provide any more rail
voltage, you won't see much [probably none] additional output power
from provide an external capacitor a long way away from where the power
is being used.

To the OP, long term power is determined by how much current the
electrical system can source. And peak power is determined by the
amplifier's power rails. Therefore, if you're seeing a large voltage
drop you need to add more current output to the electrical system. A
capacitor is just slightly [if at all] slowing the voltage fluctuations
on the power line going to the amp. Because music has such a high crest
factor a cap doesn't buy you much, if anything. If you are seeing large
voltage swings, and especially if components are cutting out, you need
to add more current capacity to the electrical system. Beefing up the
amount of wire carrying the current also helps, but not by so much
since the continuous power is low. You can safely choose wire based on
temperature and not ampacity.


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eezip