What is the best or easiest way to check what the watt output is on an amp? ie. I would like to know what the "actual" watt output is.

I have a newer Pioneer GM-7100M mono amp which I think is not supplying the power for which it is rated. Broken? The local repair shop says it works but couldn't give me the "actual" output.

I have connected the GM-7100M to one 12inch 200RMS 4ohm sub and it sounds quiet and also I've compared it against another smaller Pioneer 100RMS amp which was WAY WAY louder. Polarity correct, same type of connections and all. Strange...

The GM-7100M specs are:
Continuous Power (4 ohm) 250W x 1 RMS
Continuous Power (2 ohm) 360W x 1 RMS
Peak Music Power 800 Watts.

Any testing ideas appreciated!

 

For a rough idea play a test tone through your woofer and measure the amp's output using a DMM...

Ideally you should have a true RMS meter... but a good non-true RMS DMM will work as long as the tone is pure sine wave... on the other hand some cheap units may show extreme variations in voltage with frequency and are only accurate at 60hz...

The tone should be low, like 20hz which should correlate fairly closely to the DCR of the woofer... if you're using a cheap unit test at 60hz and read up on using a wheatstone bridge to measure the impedance at 60hz...

After you run the tone, quickly measure the subs impedance at your test frequency, or just measure the DCR if you're using a low freq tone...

Then use the equation Voltage^2/Resistance = Power


Good luck, have fun... [img]graemlins/thumb.gif[/img]

[ December 05, 2005, 09:52 AM: Message edited by: Haunz ]