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View Full Version : Meyer M-Noise A new test signal.



1audiohack
02-12-2019, 10:10 PM
https://meyersound.com/video/introducing-m-noise/

Check this out! After this video if you are still interested there is an application video on the next page with much more detail.

Being a test geek this I must have. I see this as useful for much more than just how loud will this speaker play.

Barry.

Mr. Widget
02-12-2019, 11:21 PM
Very interesting... I'll see if I can get more info. Meyer is doing some crazy good stuff these days. Did you notice the blue horned speaker sitting on the stage? They have the imaginative name of Bluehorn. Bluehorn is their version of SOTA studio monitor. It may not be a looker, but it is wicked good.


Widget

SteveJewels
02-13-2019, 05:09 PM
Nice!

The place that I am working at now has a spectrum analyzer that does an FFT to Freq domain conversion and starts at 3 Hz. :) It has me thinking about things.



Thanks for the cool post 1audiohack.

1audiohack
02-13-2019, 08:03 PM
I thought that was funny also. Well blue is easy to remember haha.

I have long believed and sometimes argued that declining bass quality and a bloom in midbass with increasing level is not “over powering the room” or reverb / reflection / room mode nonlinearity but rising distortion of the woofers.

The ultra low distortion woofers have cemented that theory in my mind as this phenomenon is utterly absent with the Al series Everest woofers and is largely mitigated by the Fe and 2216Nd woofers.

This test protocol could be a big help to me far beyond looking at “how loud will it play”.

Anything you find out will be of interest to me.

I hope it will run in SMAART which I already own. Buying SIM-3 cannot be inexpensive.

Barry.

1audiohack
02-13-2019, 09:19 PM
Nice!

The place that I am working at now has a spectrum analyzer that does an FFT to Freq domain conversion and starts at 3 Hz. :) It has me thinking about things.

Careful Steve! It’s a deep hole! Haha.

How are you?
Barry.

Mitchco
02-14-2019, 02:31 PM
Thanks Barry, very interesting!

More here in case folks did not see it: https://m-noise.org/ Including the ability to download the test file...

The videos are pretty good and a few funny bits. When adding 50% distortion to the music, "if you can't this difference, then you need a new career" LOL!

As an overview, makes a lot of sense comparing the input and output as a transfer function in real time. Will be interesting to see what the industries uptake on this will be...

Kind regards,
Mitch

SteveJewels
02-15-2019, 05:02 AM
Careful Steve! It’s a deep hole! Haha.

How are you?
Barry.


Doing good Barry.

Yeah, I've been playing around the edge of this hole for a long time. Falling in is pretty much a given, When is about the only question. :)

If I understand the premise of the m-noise thing, they are saying there is more content with respect to amplitude as a function of frequency in live performance and cinema audio so a test signal that is weighted more to the higher frequencies will be a more representative test of the system and permit analysis and adjustments that will result in a playback system that is more capable of reproducing the original content lineally, X in, X + Y out at all frequencies.

Although I was not aware of this phenomenon specifically, I have always argued for a home system that has what most consider, excessive dynamic range, that is to say, drivers and amplifiers, and enough of them, that they are always operating in their linear range.

If the source music, at whatever loudness, doubles in volume, does your system have 10 dB of headroom left?

SteveJewels
02-20-2019, 04:04 AM
To continue this thought, if you turned up the system gain the resulting SPL would increase more in the upper frequency range which happens to be where the CD's are.

Perhaps this contributed to why JBL was so successful in sound reinforcement.

I read the FAQ. The M-Noise source audio file is being distributed free and according to the FAQ works as a drop in replacement for a pink noise or whatever noise file is used.

1audiohack
02-22-2019, 10:06 PM
Hello Steve and All!

We are so covered up at work I haven't had time to hardly think about this. I also noted that the wav download was available.

I haven't found if the whole noise packet is pseudo random like MLSSA or just the dynamic peaks but I would guess it all is.

My hope is that I could tell with some precision where a system begins to slip out of linearity while it is busy with a broad band signal. This I think would be truly valuable. Jet engine SPL pink noise, oh boy.

Barry.

1audiohack
03-18-2019, 09:23 PM
Small update:

M-Noise does in fact work within SMAART.

My subs at the shop (5749’s) have substantial harmonics to that flood into the midbass at lower drive (~40V) than I thought.

Barry.