Amp Wattage

[1057985 10+ year member]

Is there a way to measure the number of watts my amp puts out

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[maylar 10+ year member]

Sure, there's a couple of ways depending on how much equipment you have available.

Best method:

Get an AC Ammeter and an oscilloscope. Put the ammeter in series with the speaker and the 'scope across the speaker to measure voltage. Put a test CD in your deck that has a continuous tone (1000 Hz for full range systems, maybe 50Hz for subs). Turn the volume or gain up until the waveform starts to clip (flatten) at the peaks. Measure the peak-peak voltage and the current and multiply those numbers and then divide by 2.82. That'll be RMS watts.

2nd best method (no scope):

Use an AC Voltmeter instead of the scope. Turn it up till it just distorts. Multiply rms volts X rms amps and you have rms power.

3rd method (voltmeter only)

Measure the AC voltage at the speaker when it just starts to distort and calculate:

Power = volts squared / speaker impedance (ohms).

The 3rd method is least accurate because actual speaker impedances vary considerably from published numbers.

 

[1057985 10+ year member]

Where can I get a test CD or where can I download some test music

Also, how can you measure speaker impedances?

 

[Jeff 10+ year member]

limewire or morpheus, and ohmmeter

 

[maylar 10+ year member]

The Bass Mechanik 5.0 CD has test tones, I found it at KMart.

Measuring speaker impedance is complicated. What you measure with an ohmmeter is close but doesn't include the AC component. Use the published spec (4 ohms, 2 ohms, whatever the mfgr says).