Is everyone smoking crack today?
Output connectors are Neutrik NLT4Ms which are spec'ed at 50A RMS @ 250V (12500W max) per contact, and there's 4, so 25000W total capacity per output connector. With that in mind it's pretty obvious that the power connectors are more than sufficient for 3x32A @ 400.
I'm pretty sure it's an output filterless design, btw.
Remember, this is meant as a professional power amp, not a whiney angel dusted hi-end amp, so it's actually real engineers designing it, and not divine inspiration.
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I just recently found this promo video of those PKN stuff:
2011 Pro Audio gear and Lighting show in London (PKN amplifier stand) - YouTube
At the end of video a big military connector is clearly visible on the back of the amps.
2011 Pro Audio gear and Lighting show in London (PKN amplifier stand) - YouTube
At the end of video a big military connector is clearly visible on the back of the amps.
There are 2 PDFs on that page. The second one shows that indeed the amp DOES have output filters. At this power, a filterless design would be a highly effective communications jammer... heck it'd probably jam itself as well because it's controlled by a CPU.
The power supply design also talks about 7.5kW continuous not anything more. And they want us to believe that the 4x4 cm transformer they show can deliver 7.5kW. Seriously? It's just another overpriced boombox IMO. Even if the power supply does 7.5k, where did the other 32.5kW come from?
The power supply design also talks about 7.5kW continuous not anything more. And they want us to believe that the 4x4 cm transformer they show can deliver 7.5kW. Seriously? It's just another overpriced boombox IMO. Even if the power supply does 7.5k, where did the other 32.5kW come from?
I think you have seen the internals of the XE amps NOT the 3PHASE... I would like to see internal pictures of the new series too.
Anyways our company (where I work) owns some of the racks full of those XE amps and YES they have 7500W continous power from that small transformer.
Anyways our company (where I work) owns some of the racks full of those XE amps and YES they have 7500W continous power from that small transformer.
I have not seen any internal pictures of PKN 3PHASE just their XE series on that webpage.
Anyways our company has some of racks full with those XE amps and their 7500W continuous power capability is not a question rather than a fact 😉 they are pretty powerful.
Anyways our company has some of racks full with those XE amps and their 7500W continuous power capability is not a question rather than a fact 😉 they are pretty powerful.
No. That's the XE/XD series power supply. A 3 phase power supply design is vastly different, and can be made much more compact. First of all, you don't really need power caps.
I'm not sure why anyone doubts the claims made by this amp. PKN is a highly regarded serious professional amplifier brand that is know for extreme reliability.
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I'm not questioning their reliability. I'm just saying that they pulled those numbers out of a hat.
Mains power draw specs clearly show it is not 40kW constant power device, not even close, unsurprisingly.
However it still looks interesting, they specify it is soft-switching design so the efficiency can be well in 95-98% efficiency range.
However it still looks interesting, they specify it is soft-switching design so the efficiency can be well in 95-98% efficiency range.
My concerns about the amplifier remain. These are my concerns:
The power connector is far too small to handle the current demand. I'm betting that it won't meet the minimum electrical codes in many countries.
The output connectors are rated at 40A with a 50% duty cycle for AC.
The amplifier may have been designed by real Engineers. I am also a real Engineer.
To design an amplifier for professional/commercial service which pushes the limits of the connectors is poor engineering.
A three phase power supply does need filter capacitors. About one-third the size of a single-phase supply.
A 40,000 watt Class D amplifier that does not include L/C output filtering would produce enormous amounts of RF interference.
At this power level (even with balanced outputs and filtering) this amplifier and the speaker cables will radiate a good amount of RF energy.
One final thought. Did anyone notice that the amplifier in the youtube video was not connected to an output load?
I would think that the company would want to put the amplifier on a load with a meter to indicate the actual power being delivered from the amplifier.
The power connector is far too small to handle the current demand. I'm betting that it won't meet the minimum electrical codes in many countries.
The output connectors are rated at 40A with a 50% duty cycle for AC.
The amplifier may have been designed by real Engineers. I am also a real Engineer.
To design an amplifier for professional/commercial service which pushes the limits of the connectors is poor engineering.
A three phase power supply does need filter capacitors. About one-third the size of a single-phase supply.
A 40,000 watt Class D amplifier that does not include L/C output filtering would produce enormous amounts of RF interference.
At this power level (even with balanced outputs and filtering) this amplifier and the speaker cables will radiate a good amount of RF energy.
One final thought. Did anyone notice that the amplifier in the youtube video was not connected to an output load?
I would think that the company would want to put the amplifier on a load with a meter to indicate the actual power being delivered from the amplifier.
Besides, how the hell would one draw 80A from a standard 230v line anyway? Good point regarding the current spec of the connectors too, this is yet another hint that the powers are fabricated. And based on their specs table, the upcoming "40kW" amp apparently violates Ohm's Law in all but the most optimistic input voltage configuration! 😱
That's what i was saying. It won't be filterless anyway.
It was just for show. 🙂
Anyway, back to the real world. If you download the datasheet for the existing XE and XD series you will notice that all ratings are given as peak (including the consumption ratings). More specifically, the output power testing is done as 1:3 burst at 1kHz. That is one cycle on, three cycles off. In laymen's terms: Divide by three and you will get the real power output. Which brings us to much more credible levels. 🙂
Also notice there are no numbers given for lower frequencies, and the absolute lack of distortion measurements - the power testing could have been done with 50% THD FWIW...
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Why not? My $15 toaster oven dissipates this much heat every morning, and it has a plastic shell and no heatsinks, per se. The issue isn't heat dissipation but flux across the relevant junctions, right? Toaster = huge junctions and high temps. It's a feasible engineering challenge for an amp to dissipate the required heat, I think.
Of course, nobody wants their amp acting like a toaster oven 🙂. But this amp won't.
At work, we have an Aglilent AC power supply 1750VA, running on 220V 2 Phase.
Used to synthesize 50 or 60 Hz for testing TI UCC power factor correction EVMs.
I think it will do other waveforms, I've never explored that capability. About 3
rack units high, and makes a whole lot of fan noise for sure...
We had a 3500W DC power supply that ran on 3 phase, and was 2 racks high.
But it never worked right, and we sent back to our vendor in exchange for the
next smaller model. 3500W was silly overkill, our biggest loads were only 600W
per channel (2 of three channels populated). Why would we need DC power in
such huge excess of our biggest load?
I find 40,000W claims in that size maybe not impossible, but hard to swallow.
Filterless is absurd unless the cables are too short to be antenna. Maybe this
thing wants external filter chokes the weight of an anvil?
Used to synthesize 50 or 60 Hz for testing TI UCC power factor correction EVMs.
I think it will do other waveforms, I've never explored that capability. About 3
rack units high, and makes a whole lot of fan noise for sure...
We had a 3500W DC power supply that ran on 3 phase, and was 2 racks high.
But it never worked right, and we sent back to our vendor in exchange for the
next smaller model. 3500W was silly overkill, our biggest loads were only 600W
per channel (2 of three channels populated). Why would we need DC power in
such huge excess of our biggest load?
I find 40,000W claims in that size maybe not impossible, but hard to swallow.
Filterless is absurd unless the cables are too short to be antenna. Maybe this
thing wants external filter chokes the weight of an anvil?
There are some right plonkas in this thread!
Remember this is on a 400V 3 PHASE LINE. Al this blabbering about pulling from a little 230v line is nonsense, do some reading first!
Fact is PKN amplifiers do actually deliver - unlike the majority of PA amplifiers. This has been verified by third party.
Remember that the days of lousy efficiency is over. Just look at the Peavey IPR range. These deliver Kws of power without heatsinks on the output devices. Many called bullcrap when it was announced (including me) but we were proved wrong!
Rant over 🙂
Remember this is on a 400V 3 PHASE LINE. Al this blabbering about pulling from a little 230v line is nonsense, do some reading first!
Fact is PKN amplifiers do actually deliver - unlike the majority of PA amplifiers. This has been verified by third party.
Remember that the days of lousy efficiency is over. Just look at the Peavey IPR range. These deliver Kws of power without heatsinks on the output devices. Many called bullcrap when it was announced (including me) but we were proved wrong!
Rant over 🙂
As quoted from the spec table on their website, 400v times 25 amps times three makes exactly 30 kW. Where did the other 10kW come from? Please educate me on how they got around Ohm's Law. Have you EVER wired a 3-phase circuit yourself? As for the 230v thing, they state it also works on 230v, quoting an 80 amps consumption. Which makes the discrepancy even larger: 18.4kW in, 40kW out. Sure thang...
Just because you decide to ignore the laws of physics, it doesn't mean they cease to exist.
As for the Peavey IPRs, they do have heatsinks on the output devices, they are not mounted in free air. The PCB acts as a heatsink. And their quoted power output is much more sane. Also note that they have been really slow in rolling out the higher powered models - the top-of-the-line IPR6000 hasn't hit the shelves yet.
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Guys, just check yourselves how a 40kW frequency converter or a 40kW UPS looks like.
Keep in mind that the devices mentioned are extremely optimized for efficiency with switching frequencies way below 20kHz.
Get real.
P.S. They are non-isolated (transformerless) devices too.
Keep in mind that the devices mentioned are extremely optimized for efficiency with switching frequencies way below 20kHz.
Get real.
P.S. They are non-isolated (transformerless) devices too.
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For all those who still have doubts that can be done:
99% efficiency AC-DC converter, PFC stage http://www.pes.ee.ethz.ch/uploads/tx_ethpublications/078_1235.pdf
99.2% efficiency DC-DC converter : http://www.pes.ee.ethz.ch/uploads/tx_ethpublications/IPEMC_09_Pareto_PFC_as_published.pdf
99% efficiency DC-AC inverter: HERIC Topology: How a Brilliant Idea Brought 99% Efficiency For Solar Panel Inverters | The Green Optimistic
A rough comparison for a class D mains powered amplifier which consist of a AC-DC stage (PFC or simply rectified mains if high PF is not required) a DC-DC converter (the power supply) and the class D amplifier power stage, not too different from a power inverter, (do not consider the different switching freq. of the amp and inverter, with soft commutation techniques the losses are similar)
using state of the art examples we get 3*99%=97% global efficiency. and that's without using exclusively GaN transistors.
LE: forgot to mention about the size.
yes, it can fit into a 1RU case. we can see from that picture that is quite long, perhaps 45-50cm. and the inductors can be made from other materials than the common ferrite, such as amorphous magnetic cores which can admit much larger flux densities.
99% efficiency AC-DC converter, PFC stage http://www.pes.ee.ethz.ch/uploads/tx_ethpublications/078_1235.pdf
99.2% efficiency DC-DC converter : http://www.pes.ee.ethz.ch/uploads/tx_ethpublications/IPEMC_09_Pareto_PFC_as_published.pdf
99% efficiency DC-AC inverter: HERIC Topology: How a Brilliant Idea Brought 99% Efficiency For Solar Panel Inverters | The Green Optimistic
A rough comparison for a class D mains powered amplifier which consist of a AC-DC stage (PFC or simply rectified mains if high PF is not required) a DC-DC converter (the power supply) and the class D amplifier power stage, not too different from a power inverter, (do not consider the different switching freq. of the amp and inverter, with soft commutation techniques the losses are similar)
using state of the art examples we get 3*99%=97% global efficiency. and that's without using exclusively GaN transistors.
LE: forgot to mention about the size.
yes, it can fit into a 1RU case. we can see from that picture that is quite long, perhaps 45-50cm. and the inductors can be made from other materials than the common ferrite, such as amorphous magnetic cores which can admit much larger flux densities.
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