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hypex power ratings

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AdamG

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changer

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Actually, I have learned a lot whilst watching this here happening live on the screen, so it cannot only be emotional (I have to say I am not a fan of "emotional intelligence"). I learned about the limiting factor of thermal management and output caps and I did not know this before. For example, I thought the smallest plate amp (with NC122MP modules) could confidently power a speaker at HiFi listening levels AND alternatively Professional Audio, because the woofer would not ever need more than 60 watts at any time. But now I now, it will probably not get this energy over a sustained period and the amp might even shut down. And I should think about a speaker mounting enclosure with some circulation. I did not know any of this before this started and I cannot judge whether some specific set of rules is 'right'. But there is probably more that I can learn about the compromises with this amps, so please continue. :D
 

Matias

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About 10 days ago I spent an afternoon running my Hypex NCore NC500 based amp into the difficult load of 2.7 ohms from my Thiel CS3.7, playing lots of compressed rock blasting loudly through the speakers for several hours. No overheating and lower power here, it just works.

This is the reality, not some meaningless bench test.
 

Jdunk54nl

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These amplifier specs are interesting to me compared to speaker specs. A 100w RMS rated tweeter isn't really ever going to be able to take 100w RMS. Speakers are rated based on music and/or pink noise. Most tweeters would be fried at much over ~5w-10w RMS for any length of time. If you don't believe me, go ahead and try it for yourself...just use some tweeters you don't care about.....

So why not have amps rated based on pink noise? It is a consistent thing that most resembles music. I don't know the feasibility of doing this with amps, but it seems the most reasonable thing to do.

Here is a nice article written by Andy Wehmeyer on it.
https://www.audiofrog.com/pink-noise-white-noise-and-why-your-tweeters-never-get-150-watts/

Here is an excerpt from it:

Let’s say we have a 3-way speaker system in which the sensitivity of the speakers are all the same—this will make the explanation a little easier. So, in our system, we have a 1000 watt amplifier. We’ve set the gain so that the amplifier makes 1000 watts at 20 Hz. In order for the system to reproduce pink noise accurately without clipping, the only frequency at which 1000 watts is necessary is at 20 Hz. At 40 Hz, only 500 watts are necessary. At 80 Hz, only 250 watts are necessary, and so on and so forth.

Since this is a 3-way system—a subwoofer, a midrange/midbass and a tweeter– the most power that the midrange, crossed over at 80 Hz, could possibly get in order to play pink noise accurately is 250 watts. The most power the tweeter would ever get, crossed over at 2.5 kHz is 8 watts.

Right. Eight watts. Just eight watts.

Power testing for speakers is often performed with the speakers playing pink noise (or some other similar noise shape). The test is calibrated so that the highest level of the pink noise is set for the test as a reference voltage (or power). Then, that noise is played over the speakers for some period of time to see if the speaker will “handle” it without the coil burning up. For testing tweeters and midrange speakers, a high pass filter is used. That filter can be passive (in the case of a component system) or it can be applied to the noise after the level calibration.

So, your 100 watt tweeter is designed to handle 100 watts in a system in which it will reproduce only the highest frequencies in the signal. Is this BS? No. If I hook up a 100 watt amplifier to my tweeters and apply the correct high pass filter, the tweeter, rated to handle 100 watts will work just fine.

Pink noise is used for this test because it has a power distribution similar to music.
 
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davidr3032

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Its been a while now and after a lot of discussion, unfortunately I don't really think I've gotten an answer to my question. I'm still unsure of what the power ratings of these hypex amps are. What drew me to this forum was I wanted to avoid a lot of the audiophile mumbo jumbo you get elsewhere. But instead I've got specification mumbo jumbo :)

March Audio it seems to me you could end this debate very easily if you just gave more detailed specs on your amps. For example, for your p502 amp your website states -

Power Output
2 Ohms - 450 W rms
4 Ohms - 500 W rms
8 Ohms - 350 W rms

But these numbers mean nothing to me without context. You say its continuous power, but is this full bandwith? 1% thd? Or what?
It seems to me that this is fairly basic info I need to know as a consumer. The fact that you don't agree with the common way amplifiers are measured isn't an excuse to just provide vague power ratings like this

Also perhaps you could provide an additional power rating figure that would conform to the FTC standard. You are selling amps to folks in the US so it seems only fair.

Then with these two numbers people can make an informed decision. You say your amps would perform well with the FTC test and have no problem with continuous power. So I dont see why that would be a problem. Presumably you've tested your amps rigorously so you should have the numbers to hand. And it's no use telling people to go looking though the specs and graphs from hypex instead. As the average consumer shouldn't be expected to understand these anyway. And they aren't the specs specifically for your finished amps

Then there would be no need for further debate. Thats the great thing about science. Accurate specific scentific data removes the need
 
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sigbergaudio

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If we try to dumb down what Marchaudio has been trying to say for 10 pages:

What demands the most power is lower frequencies. The high frequencies only require a fraction of the power in comparison. Hypex can deliver the stated power ratings at lower frequencies for an extended period of time (way longer than needed for real life scenarios with a music program). So @changer - you need 60w to your woofer with a 122? You will get it, no problem.

What does this translate to? If it says 500W on the tin of your Hypex amp module, by golly it will deliver 500W for any practical purposes. We run subwoofers with Hypex amplifiers, you won't find a heavier load. Currently we're prototyping a dual subwoofer where we run dual 4 ohm drivers (3.2ohm nominal) in parallell, so we're talking a less than 2 ohm load. The amplifier has zero problems with prolonged high output even in this setup.
 

pma

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Pink noise is used for this test because it has a power distribution similar to music.

This is too much generalized, full energy is often up to mids, several kHz, and then it decays, like in this Armstrong & Ellington vinyl. Yes, above 5kHz the energy is generally limited.

1611091807967.png
 

March Audio

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This depends on heatsinks used, for both class AB or D. For example, I can run this amplifier
http://pmacura.cz/pmacfa_en.htm
at any power between 0 - 100% of the specified power continuously, no problem with the 1 hour test at any power.

When I had the Hypex NC400 modules to test here (they were sold by Hypex? few years ago, see below)
View attachment 107130

they were running too hot in that 1/3 power test.

And the class D AIYIMA A07 (that I am testing now) specified at 2x300W/4ohm switches off itself after 1 minute of 1x100W/4ohm/1kHz test.

So it is definitely not true that is a "(total non issue for class d)", as you are saying. No, it is a question of design for any class of amplifiers. Inadequately small heatsinks will make the amp to fail in this test, regardless its class of operation.

As you know, Hypex NC500 OEM datasheet states that continuous power is only 1/5 of the "Peak Output Power" as per their specs. I hope I do not need to paste this datasheet again. It is the old game of "Peak Power", which has been with us for at least 50 years and has not changed and the main reason is marketing.
I don't know what you were doing to make the nc400 run too hot but you will see countless reports on the net saying that they run practically cold just bolted to a simple, small thin sheet amp enclosure. That certainly was my experience when I had some.

Purifi amps are even more efficient and will even run quite happy directly on the bench without any additional heatsinking. You simply can't do that with class A or A/B. They require far, far more heat dissipation.

As has been pointed out 1/3 output power is close to worst case scenario for A/B amp power dissipation. Its also 50% efficiency for A/B v >90% for class D. In any real world sense it really is a total non issue for class d.

It's also not peak power in the sense you are making out. I'm not going to have this conversation with you. You have been proven wrong with all the data in this thread.
 
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Jdunk54nl

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This is too much generalized, full energy is often up to mids, several kHz, and then it decays, like in this Armstrong & Ellington vinyl. Yes, above 5kHz the energy is generally limited.

View attachment 107193

This music sample begins at nearly -15db and most under -20db. Nothing is even close to 0db....Pink noise at least starts out at 0db and therefore would be more demanding than this music sample....If you would overlay a pink noise track, it would literally be above this music sample THE ENTIRE TIME. Pink noise bottoms out at -30db....

Edit*
Here is some pink noise generated via REW set at -2.20dbfs which results in a 0dbfs peak.
Note. This maxes out at 80,000hz, 20,000hz is at ~-34db. 80,000hz is still at ~-40db....nearly higher than most of that music you linked....
Screen Shot 2021-01-19 at 14.48.19.png
 
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March Audio

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I

March Audio it seems to me you could end this debate very easily if you just gave more detailed specs on your amps. For example, for your p502 amp your website states -

Power Output
2 Ohms - 450 W rms
4 Ohms - 500 W rms
8 Ohms - 350 W rms

But these numbers mean nothing to me without context. You say its continuous power, but is this full bandwith? 1% thd? Or what?
It seems to me that this is fairly basic info I need to know as a consumer. The fact that you don't agree with the common way amplifiers are measured isn't an excuse to just provide vague power ratings like this

I will go one better, I will put the entire thd + n plot on website.

However as should have become clear by now your other criteria that are based on the flawed FTC test are meaningless.
 
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March Audio

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This music sample begins at nearly -15db and most under -20db. Nothing is even close to 0db....Pink noise at least starts out at 0db and therefore would be more demanding than this music sample....If you would overlay a pink noise track, it would literally be above this music sample THE ENTIRE TIME. Pink noise bottoms out at -30db....
This.
 

direstraitsfan98

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Someone told me hypex module have 20 degree phase shift at 20khz and this results in loss of detail. True?
 

March Audio

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This is too much generalized, full energy is often up to mids, several kHz, and then it decays, like in this Armstrong & Ellington vinyl. Yes, above 5kHz the energy is generally limited.

View attachment 107193
As pointed out pink noise doesn't behave like you think.

Also if it were a real world issue as you have been making out, how do you explain how active speakers can work just fine with tweeter amplifiers significantly lower powered than their woofer amplifiers?

KEF LS50 Wireless
Frequency response 45 – 47,000 Hz ±3 dB (depending on settings)


Power output
200 W low frequencies,
30 W high frequencies

Maximum SPL106 dB


Crossover is at 2.2kHz

Do you think all active speakers crap as a result?
 
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March Audio

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Someone told me hypex module have 20 degree phase shift at 20khz and this results in loss of detail. True?
There is a bit of a misunderstanding about phase shift.

Yes they haveca phase shift but due to its rate of change it is actually just a (very small) time delay that's essentially equal across the frequency range. A pure time delay has no impact on the sound at all.



@Sagittarius: Class D has achieved very low levels of distortion, but is it possible for class D amplifiers to continue their evolution into something close to a straight wire with gain, i.e. minimal phase shift in the audio band? (A similar question from maty).



Bruno: The 1ET400 module has the frequency and phase response of a 2nd order Butterworth filter cornering at 60kHz. If you look at the phase shift of that, it’s very nearly “linear phase” in the audio band. To take some rough numbers, it if you have a circuit that has a 0.2 degree phase shift at 200Hz, 2 degrees at 2kHz and 20 degrees at 20kHz, that’s the same as saying it has “0.001 degree per Hertz” phase shift. That’s another way of saying that the whole signal is simply delayed by 2.8 microseconds. If you plot phase shift on a linear frequency scale that’s immediately obvious because you get a straight line. Of course a simple delay doesn’t change the sound. It’s literally the same as starting your music a few microseconds later.



Lars: My dad used to say that if you left a CD in its case without playing it back, it’d just sit there accumulating massive amounts of phase shift as time went by.



Bruno: What that matters to sound is how much phase shift differs from a pure delay. Anyone who’s ever done phase measurements on speakers will remember that you have to remove the time-of-flight delay from the data, for instance by marking the leading edge of the impulse response. Otherwise the linear phase shift corresponding to the distance between the speaker and the mic completely clouds the picture. In the case of the 1ET400 module it’s just under 1 degree at 20kHz.

There never was a phase shift problem in class D, it’s simply a trick of the light that happens when you plot the phase response on a log scale without removing the fixed delay.
 
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Matias

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My "Class D FAQ" topic is long overdue... I will get around to create it eventually...
 

restorer-john

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Why does an amplifier need to have power bandwidth above 35kHz?

You've missed the point. The Hypex doesn't even have a full power bandwidth beyond 5kHz. Read their "disclaimer" (note 7).

I'd be happy with 20kHz full pwer bandwidth with a Class D. It can't achieve a quarter of that.
 

pjug

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I hope I am not beating a dead horse but I noticed that NAD also gives the FTC rating on some of their Class D amps. For example, from the manual of the M22 (nCore):

Continuous output power into 8 ohms and 4 ohms (Stereo mode) 300 W (20 Hz-20 kHz at 0.1% THD, both channels driven)
Continuous output power into 8 ohms (Bridge mode) 900 W (20 Hz – 20 kHz at 0.1% THD)
THD+N (20 Hz – 20 kHz, CCIF IMD, SMPTE IMD, DIM 100) <0.005 % (250 mW to 290W, 8 ohms and 4 ohms) Note: Measured with Audio Precision AUX-0025 or Prism dS-LPF passive low pass filter


So maybe the hypex amps can deliver a lot of power at 20KHz?
 

restorer-john

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No. John is on ignore and wrong for the reasons pointed out over and over again. I can't be bothered to listen to his FUD

He doesn't understand the technical reasons why the things he thinks are important are of no relevance.

It's all pretty basic but he just doesn't get that music is not continuous sine waves.

He doesn't understand that music power content reduces dramatically with increasing frequency.

Until he takes these simple facts on board and acknowledge the flaws of the blunt instrument the FTC test is, its clear that he will continue to make this uninformed noise and threadcrap any subject to do with class d.

It's just best in this case to not indulge and just ignore him.

Just curious, has anyone ever heard any complaint from anyone that Hypex amps don't live up to expectations with respect to their power output? Anyone herd any reports of them shutting down due to temp? I haven't.

Standard procedure. Attack the man, not the content. Don't address any specific points and call it all FUD. Wow, that's child-like behaviour. :facepalm:

Read @DonH56 's considered and balanced post.
 

tmtomh

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You've missed the point. The Hypex doesn't even have a full power bandwidth beyond 5kHz. Read their "disclaimer" (note 7).

I'd be happy with 20kHz full pwer bandwidth with a Class D. It can't achieve a quarter of that.

Why mention "special-needs tests" and 200kHz Class AB amp bandwidth if bandwidth is not the point?
 
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