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Electronics => Beginners => Topic started by: kasumyku on July 16, 2013, 08:26:13 pm

Title: audio amplifier output rms wattage question...
Post by: kasumyku on July 16, 2013, 08:26:13 pm
Hello everyone,

When testing for rms output wattage of an audio amplifier, do all channels must have dummy loads connected in order get accurate readings, or just only one?

Thanks!!!
Title: Re: audio amplifier output rms wattage question...
Post by: Zero999 on July 16, 2013, 08:39:50 pm
All loads should be connected, to accurately measure the output power as the power supply voltage can drop under load.
Title: Re: audio amplifier output rms wattage question...
Post by: kasumyku on July 16, 2013, 09:19:01 pm
thanks hero999 !!!
Title: Re: audio amplifier output rms wattage question...
Post by: Odysseus on July 17, 2013, 01:56:25 am
To be technically correct, you will be measuring average power, which is the product of the RMS (or heating value) of the voltage and current. The phrase "RMS power" or "RMS wattage" is a bit redundant.

I remember this because I used the very same phrase when talking to a co-worker right before receiving a brief lecture from said co-worker.  :D
Title: Re: audio amplifier output rms wattage question...
Post by: vk6zgo on July 17, 2013, 06:36:56 am
To be technically correct, you will be measuring average power, which is the product of the RMS (or heating value) of the voltage and current. The phrase "RMS power" or "RMS wattage" is a bit redundant.

I remember this because I used the very same phrase when talking to a co-worker right before receiving a brief lecture from said co-worker.  :D

And rightly so! Even if the Root Mean Square value of a power waveform had any practical use,it still would not be the product of the RMS values of voltage & current.