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<blockquote data-quote="dB-r" data-source="post: 6702673" data-attributes="member: 574699">Also note, in a lot of newb clamp tests (and pros) I see people claiming ridiculous numbers from some amps, and lots of times it shows as if the amp were more than 100% efficient.i.e.&nbsp; Say someone says a D9 puts out 9800 watts @ 1 ohm...Let&#039;s say they read 99VAC and 99AAC so 9801 watts @ 1 ohm....BUT THEN they show the DC clamp and VDC on the power wires for the test as say:625ADC @ 12VDC... Well, that&#039;s only 7500 watts.... So the amp is only using 7500 watts so WTF did the clamped output say 9800 watts?&nbsp; How is that possible....When you run an amp into clipping, it doesn&#039;t draw anymore current, the output signal just gets overdriven and the clamp meters will show the distortion as clamped power.....&nbsp; simple.&nbsp; The meter picks up the clipping as extra amps or voltage...So to do an absolutely accurate test you need to monitor DC input voltage, DC input Amperes, AC Speaker output Volts and AC Amps, and use an oscilloscope on the output of the amp to watch the output signal.&nbsp; When the tops or bottoms start to look flat or the signal starts to look square going to your speakers, you are clipping the signal and the meters will keep going up, the sub may get a little louder, but the amp is not putting out clean power, which would be a SINE WAVE, instead it is putting out a SQUARE WAVE which sounds like a chainsaw (or farting sound in the coil of the sub).....</blockquote>

[QUOTE="dB-r, post: 6702673, member: 574699"] Also note, in a lot of newb clamp tests (and pros) I see people claiming ridiculous numbers from some amps, and lots of times it shows as if the amp were more than 100% efficient. i.e. Say someone says a D9 puts out 9800 watts @ 1 ohm... Let's say they read 99VAC and 99AAC so 9801 watts @ 1 ohm.... BUT THEN they show the DC clamp and VDC on the power wires for the test as say: 625ADC @ 12VDC... Well, that's only 7500 watts.... So the amp is only using 7500 watts so WTF did the clamped output say 9800 watts? How is that possible.... When you run an amp into clipping, it doesn't draw anymore current, the output signal just gets overdriven and the clamp meters will show the distortion as clamped power..... simple. The meter picks up the clipping as extra amps or voltage... So to do an absolutely accurate test you need to monitor DC input voltage, DC input Amperes, AC Speaker output Volts and AC Amps, and use an oscilloscope on the output of the amp to watch the output signal. When the tops or bottoms start to look flat or the signal starts to look square going to your speakers, you are clipping the signal and the meters will keep going up, the sub may get a little louder, but the amp is not putting out clean power, which would be a SINE WAVE, instead it is putting out a SQUARE WAVE which sounds like a chainsaw (or farting sound in the coil of the sub)..... [/QUOTE]

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