NC400 FFT Plot

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mgalusha

NC400 FFT Plot
« on: 4 Jun 2012, 02:08 am »
For anyone who is interested, the FFT plot below if from an NC400/SMPS600 combination, 1W output power into an 8 ohm load.

The 2nd order harmonic is about 110dB down, 3rd and 4th harmonic at perhaps -115dB and higher orders even lower or in the noise floor.

Plot generated using Prism Sound dScope III.



jtwrace

Re: NC400 FFT Plot
« Reply #1 on: 4 Jun 2012, 02:09 am »
 :o

poseidonsvoice

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Re: NC400 FFT Plot
« Reply #2 on: 4 Jun 2012, 03:33 am »
 :o :o

 :D

 :thumb:

Anand.

*Scotty*

Re: NC400 FFT Plot
« Reply #3 on: 4 Jun 2012, 03:51 am »
Mike, the FFT looks pretty good, the higher harmonics should be attenuated by the output filter so they will look increasingly better as the frequency goes up.
 It's certainly hard to find fault with how this amp measures.
Thanks for the new data, this is the first FFT I have seen of Brunos's new baby.
Scotty

roscoeiii

Re: NC400 FFT Plot
« Reply #4 on: 4 Jun 2012, 04:20 am »
Whoa.

SlushPuppy

Re: NC400 FFT Plot
« Reply #5 on: 4 Jun 2012, 04:27 am »
Thanks Mike!

Rclark

Re: NC400 FFT Plot
« Reply #6 on: 4 Jun 2012, 04:52 am »
  you know, you can't say hypex without...hype  :green:

   

kevinh

  • Jr. Member
  • Posts: 102
Re: NC400 FFT Plot
« Reply #7 on: 4 Jun 2012, 12:56 pm »
The distribution of the distortion harmonics looks favorable, if the relation of harmonics remains as output level is reduced that could explain a lot of good sound people report.

Occam

Re: NC400 FFT Plot
« Reply #8 on: 4 Jun 2012, 09:47 pm »

TomS

Re: NC400 FFT Plot
« Reply #9 on: 4 Jun 2012, 09:55 pm »
WOW!!! Thats an incredibly cool new toy tool.
http://www.prismsound.com/test_measure/products_subs/dscope/dscope_functions.php



I'd be totally geeked out just looking at it, much less trying to figure out how to use it. There was a happy time in my engineering career when the boss would come in some time in December and say "we still have $xyz budget left to spend for the year, so what should we buy?". This would definitely make that kind of list.

So many uses for it and, well, it's just way cool  :thumb:

brj

Re: NC400 FFT Plot
« Reply #10 on: 4 Jun 2012, 10:04 pm »
Very cool, Mike!

Let me know if you run out of things to measure... I'd be happy to bring random pieces of gear by to be measured just for the curiosity and coolness of it! :)

gooberdude

Re: NC400 FFT Plot
« Reply #11 on: 4 Jun 2012, 10:06 pm »
So do the plots that Mike posted surprise anyone?   Are they difft than what the mfgr has posted?


roscoeiii

Re: NC400 FFT Plot
« Reply #12 on: 4 Jun 2012, 10:11 pm »
Moreso for speakers, but I think a lot of folks regard manufacturers' plots as suspect. Data can be goosed to look favorable by interested parties...

mgalusha

Re: NC400 FFT Plot
« Reply #13 on: 4 Jun 2012, 11:55 pm »
Data can be goosed to look favorable by interested parties...

I have no interest other than seeking the facts. That is as raw as it gets, I have just barely figured out how to measure even that, no diddling with the number of data points, no smoothing, just a raw trace exported to a jpg. Given than Jan Didden posted a couple weeks ago about attending a seminar where Bruno demonstrated the measurements were indeed real and Jan made strong mention of the fact that the distortion actually dropped at higher frequencies vs rising as do almost all amplifiers, I am pretty certain the Hypex are not tweaking the data to make it look good.

mike

Edit, btw, not trying to hammer on roscoeiii, just trying to be straight.

mjosef

Re: NC400 FFT Plot
« Reply #14 on: 5 Jun 2012, 12:02 am »


So what kinda aftermarket power cord are you using on that ?  :lol:

mgalusha

Re: NC400 FFT Plot
« Reply #15 on: 5 Jun 2012, 12:05 am »
Yeah.... the one that came in the box. :)

jtwrace

Re: NC400 FFT Plot
« Reply #16 on: 5 Jun 2012, 12:05 am »
I have no interest other than seeking the facts.
Not to mention that spending that much dough on that piece of test equipment to muck with the numbers would be.....

Not so sure that people realize how expensive this tool is.   :o

JohnR

Re: NC400 FFT Plot
« Reply #17 on: 5 Jun 2012, 12:21 am »
How expensive is it?

SlushPuppy


roscoeiii

Re: NC400 FFT Plot
« Reply #19 on: 5 Jun 2012, 05:13 am »
Mike,

Never meant to insinuate that you might be goosing anything. Just wanted to suggest why people might not trust manufacturer measurements, since they have a very vested interest in presenting their products in the best possible light.

The measurements in this thread are very much appreciated.

Best,
Roscoe