No, they shouldn't. They should be measured handling real life conditions not arbitrary and outdated measuring methods which has no relevance to the actual use.
Like 300HP car should produce 300HP at the wheels and most of the rpm range, yet it doesn't
... and what are the real life conditions? A sine wave is a consistent waveform for measurement. It is not arbitrary.
this is not inverter, its audio amplifier, so it should be rated with music... and you wouldn't believe how much energy you can have stored in capacitors at high voltage, and crest factor of music will take "real" outputs, or what ever you want to call them, way up... and everybody here knows this won't do 40k or even 20k with sine on outputs
In modern testing you typically use gaussian noise signals which very closely resemble music signals.
Pink noise would be alright. AFAIK, that's what the AES uses for testing loudspeakers. But certainly not a meaningless burst power...
AMPLIFIERS are used with LOUDSPEAKERS. So it doesn't make any sense for the two to be tested in DIFFERENT ways. @ Saturnus: A 1kHz burst has NOTHING in common with gaussian signal (pink noise).
A Gaussian test signal is not pink noise but AWGN (additive white gaussian noise) but true, a 1khz burst is not a proper test signal for anything audio related.
I would agree that Pink Noise or AWGN would be a good test for amplifiers and loudspeakers. Sine waves are more demanding. Perhaps too demanding.
White noise would be even better than pink, because it has a lower crest factor and more high frequency content. But no one actually uses white noise to test anything... FYI:
Sine wave: RMS power is -3dB. Which means that the peak power is twice the average power. For every +3dB power doubles, for every -3dB power halves.
Square wave: RMS power is 0dB. Peak power = average power.
Pink noise: RMS power is -12dB. Peak power = 16 times the average power. The AES specifies that loudspeakers should be tested with pink noise band limited to the range the loudspeaker is expected to reproduce. That is for long term testing (several hours). Short term testing is with sinewave bursts AFAIK. There is no such long-term power testing standard for amplifiers...
White noise: RMS power is -4.8dB. Peak power = roughly 3 times the average power.
EDIT: sorry, got RMS levels mixed up with power levels. Updated.
Burst sine wave: Peak power can be anywhere between 2 times and a few hundred times the average, depending on duty cycle... So one can see how burst ratings are effectively meaningless, especially when they're given in vague marketing terms. Fully on/fully off situations are NEVER encountered in music.
Sine wave: RMS power is -3dB. Which means that the peak power is twice the average power. For every +3dB power doubles, for every -3dB power halves.
Square wave: RMS power is 0dB. Peak power = average power.
Pink noise: RMS power is -12dB. Peak power = 16 times the average power. The AES specifies that loudspeakers should be tested with pink noise band limited to the range the loudspeaker is expected to reproduce. That is for long term testing (several hours). Short term testing is with sinewave bursts AFAIK. There is no such long-term power testing standard for amplifiers...
White noise: RMS power is -4.8dB. Peak power = roughly 3 times the average power.
EDIT: sorry, got RMS levels mixed up with power levels. Updated.
Burst sine wave: Peak power can be anywhere between 2 times and a few hundred times the average, depending on duty cycle... So one can see how burst ratings are effectively meaningless, especially when they're given in vague marketing terms. Fully on/fully off situations are NEVER encountered in music.
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White noise is used for frequency response testing. White noise has equal energy across the audio spectrum.
Show it!
1.: Somebody wants to abuse it. 2.: Limiter is mandatory against it. -> Why is it mandatory? Because overdrive is not allowed!
Originally it is not for protecting amplifier, but for protecting speakers, and quality (enjoyment). But every professionals realised that forcing a capability which is never used does not worth the additional cost. So amplifier designers started to follow the demand!
Thought controlling is not the task of the designer, nor of you (or anybody)!
If someone think stupid think, it's his/her business. Building unreasonable hardver to protecting some ignorant people from making mistakes, is a nonsense.
This amplifier is perfectly cover the real demands. Thats all. Build better if you can!
Or should they say it's only 15 kW? Why? To make it easier to burn speakers? To make it less economical?
I don't need to, i'm tired of it. I hear it every day.
And the limiters are useless when the bloke at the mixer clips the signal before it even reaches the amps. But it is true, the whole power and limiting thing is just a commercial trend... and it only makes things sound worse.
If the auto or airplane industry thought the same, then the world population would have likely halved by now.
You first. I don't want to ruin your enjoyment... I do have some high power prototypes on tap but i don't have all the tools required for testing at this power level, and i'd rather back up my numbers with real test data, rather than just pull them out of my ***. My load is only good for 1.6kW or so. So they'll have to wait a couple years.
Why would rating the amplifier as 15kW make it easier to burn speakers??? It is sustained average not peak power which kills speakers... Or do you really think this amp can pop the coils of 8 18"s on a single peak? I very much doubt that. And the economical aspect is the other way round - if they'd said it was just 15kW they would have been forced to put a lower price tag.
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You don't have to proove anything, your word is the ultimate statement everybody must trust.
You don't have to proove anything, your word is the ultimate statement everybody must trust.
No way. But there can be plenty more people to prove it to you. I don't need to. By the way, the guys doing the specs on that amp haven't proven anything either.
Why would be other people's job to proove your statement?
A spec sheet is not for prooving anything. It's just a statement. Nobody asked them to proove anything.
A spec sheet is not for prooving anything. It's just a statement. Nobody asked them to proove anything.
I saw this amp at PLASA, and wondered why on earth anyone would buy it. No pro audio company I know would risk running so many speakers from one amp, it's just too risky. Besides which, most real boxes these days are self powered.
We'll see what the market does, but I share your doubts.
The only possible use for this amp I can imagine is to drive a large array of high impedance drivers in parallel. After all, who in his right mind would put drivers in series if it can be prevented. So, do those kinds of drivers actually exist, like 1000 watt RMS 20 Ohms monsters??
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