I had a reason to drive a modest power amp into clipping in a dummy load and I came up with this. Those are not
low inductance resistors, just wirewounds by Ohmite but they can tolerate 100 watts into 8 ohms, 200 Watts into
4 or 16 Ohms. The channels are totally independent so it can be used with nearly any amp. The shorting plugs are
captive so they don't get misplaced. All the resistors are 16 Ohm 50 Watt. It's not fancy but is useful now and again.
G²
low inductance resistors, just wirewounds by Ohmite but they can tolerate 100 watts into 8 ohms, 200 Watts into
4 or 16 Ohms. The channels are totally independent so it can be used with nearly any amp. The shorting plugs are
captive so they don't get misplaced. All the resistors are 16 Ohm 50 Watt. It's not fancy but is useful now and again.
G²
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Nice.
How hot do they get when under load?
I’m curious how Sine RMS power compares to “Music” RMS power. Maybe they run cooling than expected?
How hot do they get when under load?
I’m curious how Sine RMS power compares to “Music” RMS power. Maybe they run cooling than expected?
The highest power I ran into it was 1 KHz sine 130 Watts/channel at 4 Ohms for 10 minutes. It was not
too hot to hold but it was getting there. It has a modest amount of thermal mass but not much thermal
radiation (no fins). Sine RMS is the most demanding as it is continuous (crest factor =1). Music RMS is
far less demanding of the dummy load.
G²
too hot to hold but it was getting there. It has a modest amount of thermal mass but not much thermal
radiation (no fins). Sine RMS is the most demanding as it is continuous (crest factor =1). Music RMS is
far less demanding of the dummy load.
G²
Clever. You can add a line-level take-off voltage divider to that circuit if you choose which terminals are ground:
It has different divide ratios for 16 v. 4 or 8, but you might want a pot as the lower leg of the divider anyway.
It has different divide ratios for 16 v. 4 or 8, but you might want a pot as the lower leg of the divider anyway.