GB wrote:
alexander.keys1 wrote:
On Mar 4, 11:09 am, "GB" wrote:
The Natural Philosopher wrote:
Dave Plowman (News) wrote:
Just solder a new 80v cap of almost any flavour over 1000uf across
whats there.
Why would these need to be 80v out of interest? What sort of DC
voltages do these amps typically operate on? I know there's a margin
for peaks, but 80v across a nominal 8 ohm resistance would provide
800w. This is an amp, not a room heater, surely?
80 volts is the *peak* voltage, at the top of the waveform. The
wattage delivered to the speakers depends on the 'RMS' (root-mean-
square, a sort of average), which is 0.707, (for design purposes; it
varies with the waveform) of the peak.

That's still 400w average power.


only with a split rail supply.

Otherwise its about - with PSU sag and a safety margin the square root
of two times half the voltage minus about 15v, so 24v rms Or in power
terms about 132W into 4 ohms

Unless its split rail with two 80V caps, or an H bridge..in which case
yes, its abut 400W.