Looks to me like it would need at least 400V rails to do the quoted 20KW into 4 ohms, bridged. Possible off a 400V AC line, no?
Whether it's possible it would require Massively series-parallel load wiring. It would require something like 40 true 1000 watt RMS drivers (or some similarly over-reated arrangement) in order to not simply lose 10Kw to power compression anyway.
The Spec sheet says 400v times 32 amps which gives 38,400 watts in for the possible maximum AC line current draw. Providing the amp has the ability to push some peak slightly over the maximum then it could perhaps push 40kW under the right circumstances.
Granted a 240v arrangement wont get near to this, but I don't think anyone serious is going to plug it into a standard domestic wall outlet.
And how would you dump 1.2 kilowatts of heat from a 1U case? The efficiency would have to be at least 98.5% for the 40kW number to be believable.
P = V^2/R.
400^2/4 = 40,000.
So yes, it is easily possible off of three phase.
240^2/4 = 14,400 watts.
So it would indeed need to be bridged to reach a 20k watt spec into 4 ohms with 240volt operation. Of course this doesn't expect any losses, but they do mention that taking the supply below 208volts will limit the maximum output power.
208^2/4 = 10800 watts.
So if the SMPSU regulates the supply rails to a constant value, then yes, it should be able to supply the quoted power figures. That is until of course the power supply voltage drops below the required headroom to maintain the supply rails.
Power in vs power out vs 100% efficiency would dictate that the power figures are not unrealistic. What goes on inside that box to allow it to do what's written in the spec sheet however is another matter.
I think we're forgetting here that one doesn't usually design a power amp of the like (high power in small space)to be able to sustain it's rated output when driving sine waves. Sure it might be able to drive them, but usually the thermal management is arranged to be able to support music signals.
And since there is no accepted definition of "music" then manufacturers are free to pull numbers out of their rear end. And certainly, their burst testing procedure does not qualify as "music". If the numbers were obtained on pink noise, then they would've had some meaning. But a single cycle of 1kHz burst AND with no THD number... that's absolute nonsense.
Look at their power supply page. Their biggest power supply is 5kW, weighs 15.6 Kg, and comes in a 2U package. Matter of fact, all their power supplies come in 2U. And now the very same company claims 40kW output from an amplifier (which has losses in both the power supply and the audio stage), which comes in 1U, and weighs 13.7 Kg. That alone should be food for thought...
Indeed. And you'd have to go a long way to clip an amp with this power rating. 🙂
To be kind, it won't do 40KW continuous. Didn't someone mention a 3:1 ratio?
To be kind, it won't do 40KW continuous. Didn't someone mention a 3:1 ratio?
Not if their marketing tells you that two of those is all you need to replace a rack of 20 conventional amps, and you buy their blabber...
Edit: Yes, i mentioned that they used a 1kHz tone at 1:3 burst when rating the power output of their other amps. Now, i assumed 1:3 meant one out of three cycles, because it could very well mean 1 cycle on, 3 cycles off, in which case the average power would be even lower. Anyway, we had amps with 33ms burst ratings (one cycle of 30Hz). Next we had 10ms burst ratings (one cycle of 100Hz). Those are rated at one cycle of 1kHz. What's next, one cycle of 10kHz??? This is just plain ridiculous.
As far as marketing vs reality goes, there's no difference between this and the "5000W" boombox in your kitchen. Except the price of course...
Edit 2: I generated the kind of signal they use to rate their amplifiers. You're free to test whatever you please with it. 🙂
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Anyone that silly deserves the meltdown they get. 😉
I just use powered speakers (Meyer) and don't worry about it.
I just use powered speakers (Meyer) and don't worry about it.
Yes, it would be food for thought, and it tells that the requirements (and hence the operation principle and realisation) in a professional power supply are absolutely different from the ones in an amplifier.
Th3 uN1Qu3 said:
Yes, your idea is ridiculous, but reality is different. They do and will use much longer burst, and it is a stricter measurement than a strong real life music drive.
Pink noise is not suitable for measuring real power capabilities of an amplifier.
Power handling capability of a speaker has a much bigger peak-to-average power ratio, this is (one of the) the cause of the change in the specification method!
But with music signal and speaker load it's not possible to notice difference between a countinuously loadable amp, and a (good) burst specified amp.
PMPO rating found on music centres is a different thing, it is simply a lie.
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Class D amps typically are only good up till their 1/2 RMS capacity. After that, distortion rises rapidly. So, it is nice for headroom, but no one will run this thing at anywhere close to a real 40KW, rather at a 20KW RMS tops.
For my domestic situation, I would use two chanels for music, and the other two for bath water and to heat the house.
vac
For my domestic situation, I would use two chanels for music, and the other two for bath water and to heat the house.
vac
That's just as ridiculous a statement as saying that beer tastes better in glass only half full.
The thing that is military technology is the power connector(from the looks of it in the youtube video) 2011 Pro Audio gear and Lighting show in London (PKN amplifier stand) - YouTube
These are the standard connectors danish military.
Damn i look forward to seeing these amps.
and for all the non believers. as far as i can tell this should be possible. just not easy!!!
It's not MY idea! It is THEIR statement as to how they rate their amplifiers that are currently on the market. Page 3.
http://www.pknc.com/XE_series_user_manual.pdf
http://www.pknc.com/XD_series_user_manual.pdf
Also, in a lot of cases, modern music has a LOWER peak-to-average ratio than pink noise! The peak power handling capability of a speaker or amplifier does not matter, if such peaks never appear in program material. If you have a son with a 0dB peak lasting exactly 1ms, with absolute silence afterwards, let me know... And you don't buy a monster amplifier to drive tweeters! So the behavior at lower frequencies (= longer duration bursts) is what actually matters, and there is no mention of it in their specs.
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Well as a happy PKN user I can tell that those amps ( Xe and XD) can do very serious levels of sustained power at ANY frequency. I know that the XE-6000 models can have 2 X 2600W+ continuous even at 19Hz or 10KHz when booth channel loaded by 4R resistors for several minutes.
I know from my experience because the biggest low-frequency drivers roasted and burned down completely after tens of seconds when accidentally continuous low-frequency signals were present (without RMS limiting).
I have got not only test reports but I have been using those amps since several years and made test by myself. probably called "Experience" in this filed... So PLEASE try not to comment what you have never seen/touched/try....
I know from my experience because the biggest low-frequency drivers roasted and burned down completely after tens of seconds when accidentally continuous low-frequency signals were present (without RMS limiting).
I have got not only test reports but I have been using those amps since several years and made test by myself. probably called "Experience" in this filed... So PLEASE try not to comment what you have never seen/touched/try....
Where do you see that the lengt of burst is 1+2 ms? Nowhere! This is only your assumption, as you have already stated! I talked to one of the developer last year, and he told me what is the duration of the burst. I forgot the exact value, but I can assure you it is perfectly long enough! (1 second I guess, but this doesn't mean that duration is limited to 1 s by the amplifier!)
Don't try to ruin somebody's reputation without knowing them, or their product!
As many people pointed out, this design is limited thermally. Typical thermal time constants (of the critical devices) are in the order of 1 sec ... 1 min, so there is no reason to limit duration so insanely.
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Try that with dubstep music😀 It would be very noticeable.The signal is almost like a continuous sinusoide😀
I think AES should make a standard for measuring the power of an amplifier for short tine and long time.
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Please refer to AES2-1984(r2003) "AES Recommended Practice-
Specifications of loudspeaker components used in professional audio and sound reinforcement" page 8.
to discover how the best (and most powerful) speakers definied. I am sure you will be suprised, maybe shocked to see the surviable peak-to-average ratios. ;-)
Specifications of loudspeaker components used in professional audio and sound reinforcement" page 8.
to discover how the best (and most powerful) speakers definied. I am sure you will be suprised, maybe shocked to see the surviable peak-to-average ratios. ;-)
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