Phil Allison wrote:

"TonyL"

I've found a couple of HY60 amplifier modules in my junk box. I have a
data sheet which indicates a +/- 25v power supply voltage rails
requirement but no indication of current. Power into 8 ohms is 30W. If I
put a power supply together what sort of current should I be expecting to
supply to each module ?

** Class AB amps are typically about 65% efficient at full output - with
78.5% ( pi/4 ) being the theoretical maximum.

So, at 30 watts max sine wave output the DC power consumption is around 46
watts.

With +/- 25 volts rails, a DC current rating of 1 amp per amplifier ( ie 50
watts) will be fine.

Agreed 100%


Go for a toroidal tranny with twin, 18 volt secondaries wired in series (
for 18-0-18) rated at 3.3 amps (or 120VA) for a stereo amp - the extra AC
current is need in the conversion from AC to DC.

Filter caps need to be around 10,000uF - at 35 volts for safety.

I'd be happy with 4,700uF if it's only driving 8 ohms.


BTW:

Forget the mad answer Serge posted.

Quite so !

Graham