Quote:
Originally Posted by vortalexfan
I've seen and read about dummy load resistors being used when servicing stereo equipment, specifically if rebiasing an amplifier in a power amp or a stereo receiver, and parts express has some dummy load resistors rated at 8 ohms 50 watts for sale on their website but they're $30 a pop.  |
Most SS amps are around 20RMS watts (alot of 60s and newer amps use peak watts and other BS measurement units so marketing can claim a 20W amp is actually 150W when it ain't) you only need 50W if you have a 50W amp that you want/need to test at full power.....
As long as you keep the volume low you can hook a 5W dummy load to a 100W amp without issue...(well if the amp is damaged and a ton of DC is leaking into the speaker terminals that exceeds the rating of the resistor and you don't catch it quick you could loose a resistor). A good protection for dummy loads is to put a drop of water or spit or oil or something that will sizzle if the resistor overheats... that should warn you it is about to cook before it does.