You are, its called specmanship 
It probably also has a mains lead that wouldn't be out of place on a table lamp.
We used to see it a lot in the days of portable audio and car audio from the likes of Sharp who were masters at this.
Running off 8 1.5 cells they were adorned with stickers such 120w total peak instantaneous peak music power and the like.
Dig deeper into the specs for the amp and you'll soon find the holes appear. Also a single wall outlet can not even supply 5kW.
It probably also has a mains lead that wouldn't be out of place on a table lamp.We used to see it a lot in the days of portable audio and car audio from the likes of Sharp who were masters at this.
Running off 8 1.5 cells they were adorned with stickers such 120w total peak instantaneous peak music power and the like.
Dig deeper into the specs for the amp and you'll soon find the holes appear. Also a single wall outlet can not even supply 5kW.
Large filter caps can be used to provide high power peaks during short transients, allowing the PSU to be derated. Much music is very peaky so this can have benefit, but some music/content (bass-heavy for instance) is much closer to a continuous load at high power and this trick gains little/nothing.
And of course some unscrupulous manufacturers give wrong/misleading figures, such as giving instantaneous peak power rather than rms for sine waves, which are a factor of two different.
And of course some unscrupulous manufacturers give wrong/misleading figures, such as giving instantaneous peak power rather than rms for sine waves, which are a factor of two different.
Quite the contrary.
On a Class AB SS amp, 95% or more of those used, Power consumption varies with power delivered to load
, typically 20% to 30% higher because of losses, so it VERY MUCH has to do with output Power.yes ... a MINIMAL amount compared to power consumed at full Audio power output.
See above, it is MOST DEPENDENT of power supplied to load.
When idle (no power supplied to load), amp will still use a little mains power.
But of course what´s relevant is what happens when amps are doing their job.
Not even a Class A amplifier will consume 1000 watts idle/on standby.
Just an educated guess, but those specs point to a 5.000W "Marketing rated" amplifier, which probably has 700/800W RMS real rating, at which point it will pull said 1000W from Mains.
I think that might be true for a Class A amp ... but it is certainly not true for a Class AB amp.
And even more so for a Class D amp.
True. And so?
Andy
The inflated figures are usually specified as PMPO power. This ill defined power measurement does list the maximum power delivered at unspecified distortion level for a unspecified short period of time. On a amplifer, it is basically the output current at short circuit multiplied by the DC power supply value. This power comes from the power supply filter capacitors so it may be higher than the power comsuption. PMPO power is usually 4-5 times the RMS power, but I've see even higher claims such as a computer speaker with plastic cabinet and 3 inch drivers rated at 100W PMPO while the power supply brick was 12V 1A, suggesting a 4+4W RMS power.
We can only guess.
Not even a Class A amplifier will consume 1000 watts idle/on standby.
Just an educated guess, but those specs point to a 5.000W "Marketing rated" amplifier, which probably has 700/800W RMS real rating, at which point it will pull said 1000W from Mains.
As Mooly said, it's all specmanship. You can have a very short, 10millisecond, peak of full voltage in a 2 ohms load. Say you have 80V supply, that's a peak power of no less than 3.1kW.
Even is the amp can only sustain continuous power of a few 100 W.
Don't try to calculate what is not meant to be calculated ;-)
Jan
Even is the amp can only sustain continuous power of a few 100 W.
Don't try to calculate what is not meant to be calculated ;-)
Jan
Yamaha specs their amps at 1/8 power as we don't play square or pure sinusoidal waves. So 5000W would be 625W more outlet friendly. Amps are usually tested with pink noise with a determined crest factor. If they were tested to max with say a 20Hz sinusoidal wave, they would heat up in seconds and the speaker coils wouldn't last long.
Almost none. Busy lifting a bridged Hiraga from the ground, four legs each 2,5A, on +/-15Vdc rails, burning 600W. In stereo that's 1200W. Output specs on request, but 0.5Ω load is not so difficult.
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