Jitter vs no-Jitter

[bibo01]

Jitter vs no-Jitter

This picture is a Jitter test of DAC no.1. Jitter is so low at this window that practically it cannot be measured.

http://up.nexthardware.com/user_images/25259/52/medium/jitter 24.jpg


This picture is a Jitter test of DAC no.2. Jitter is high and over 200ps.

http://up.nexthardware.com/user_images/25259/52/medium/generico jitter.jpg

Question -
Listening to two equal tracks - "A1" and "A2" - recorded passing through each DAC, are we able to recognize DAC no.1 with less jitter?

In the pool options are:
1) track "A1"
2) track "A2"
3) I am not sure to hear differences.

This is a link to download the two tracks in question: http://dropcanvas.com/lljtz
The answer is in a ZIP password protected file. The answer will be given in 10 days.

Thanks for participating

 

[bibo01]

In case you have problems to download from the original link, you can download the two tracks from here too:
https://www.dropbox.com/s/i4pb51k3r6etyr6/test ascolto.zip?dl=0

 

[amirm]

I did download them eventually (it made me wait a while) but no time to listen.

 

[amirm]

By the way I don't understand the Poll questions . The files I downloaded are Dac A1 and Dac A2. How do I vote after I listen to them and let's say I can differentiate them.

 

[Gregadd]

What does jitter sound like?

 

[bibo01]

By the way I don't understand the Poll questions . The files I downloaded are Dac A1 and Dac A2. How do I vote after I listen to them and let's say I can differentiate them.

Unfortunately the site for the pool heading does not allow long questions. So mine is incomplete.
From my initial post, you are supposed to pick the DAC - and therefore the track - with less jitter


To be precise for everybody:
the two converters are the same, with the same analog output stage, only the clock of one of them is damaged and generates more jitter.

 

[esldude]

Man you need better sources than this. His video in this case doesn't really say much, and says some things just wrong. Of course he is the guy claiming in another part of this video that .2 picoseconds of jitter is readily apparent to him. Yeah, right!

You do bring up a good point by posting this. What does jitter sound like? It would be nice if it could be simply demonstrated. Not the subjective murky word descriptions in this video. I mean if we had a few excellent recordings to which someone adds controlled amounts of jitter. Start with a very high and clearly obvious amount, and then reduce it until it is gone to most people. So people could know it was jitter they are hearing and what it sounds like.

 

[Gregadd]

I remember in one of the Batman movies with Kim Basinger. The Joker(played by Jack Nicholson) remarked of Batman"Where does he get those great toys. Given the fact I already no more about digital than I ever wanted to. If I ever get those great toys and learn how to use them I'll produce it and post it on uou tube. For the moment that was the best I could find.
In the meantime you all feel free to post something better. Thanks for the critique.

 

[Mitchco]

You do bring up a good point by posting this. What does jitter sound like? It would be nice if it could be simply demonstrated. Not the subjective murky word descriptions in this video. I mean if we had a few excellent recordings to which someone adds controlled amounts of jitter. Start with a very high and clearly obvious amount, and then reduce it until it is gone to most people. So people could know it was jitter they are hearing and what it sounds like.

esldude - have you tried these? http://www.cranesong.com/jitter_1.html

bib - I will give your files a try

Cheers, Mitch

 

[esldude]

I remember in one of the Batman movies with Kim Basinger. The Joker(played by Jack Nicholson) remarked of Batman"Where does he get those great toys. Given the fact I already no more about digital than I ever wanted to. If I ever get those great toys and learn how to use them I'll produce it and post it on uou tube. For the moment that was the best I could find.
In the meantime you all feel free to post something better. Thanks for the critique.

While not beyond reproach altogether this article might be more helpful to you.

http://nwavguy.blogspot.com/2011/02/jitter-does-it-matter.html

 

[esldude]

esldude - have you tried these? http://www.cranesong.com/jitter_1.html

bib - I will give your files a try

Cheers, Mitch

Thanks Mitch. I haven't seen that or heard those. Will give them a try.

 

[esldude]

Alright listened to the Cranesong tracks.

It quickly became apparent which I thought was the best file. Which was the worst and so on. It also happens my opinion of the best was the low jitter version. My opinion of worst was the highest jitter version. My opinion of second worst was not in line with the amount of jitter so the jitter frequency perhaps played a part. I suppose I can work it out from the files, but I wished they had listed the amounts of jitter in each file. Other than the best being 13 picoseconds they didn't say unless I missed it.

I will also note that the lowest jitter file was in reverse phase to all the other files. On simply miked recordings that can matter. I wish they hadn't done that. It may not make any difference, but would have been nice to get that correctly phased versus comparison files. This is the kind of demo I think we need more of when people want to talk about what jitter sounds like or attribute various problems to jitter.

For what it is worth I was away from my main rig, and listening over JBL LSR305 monitors with a LSR310s woofer.

 

[Gregadd]

tthe first video posted on my digital Primer thread seems to think jitter can be eliminated using a PLL, There is something also called an asynchronous sampling rate converter. They can assign the misplaced data in the right place.

 

[Gregadd]

 

[amirm]

tthe first video posted on my digital Primer thread seems to think jitter can be eliminated using a PLL, There is something also called an asynchronous sampling rate converter.

A PLL does not eliminate jitter by its mere existence. In simple terms a PLL is like a big flywheel or turntable platter. It will resist speed changes but up to a point. PLLs in audio equipment are usually designed for reliability and hence, filter high frequency jitter. They sadly leave all the jitter in audio band still there. High-end implementations however, will do much more.

Here is a set of measurements I made on how much filtering occurs in a number of Audio/Video Receivers and a few high-end products:

Zero line indicates no filtering. All the AVRs are bunched up on that line.

The best product there is my Mark Levinson DAC with 50-60 dB reduction of jitter.

As for async sample rate converter, they do get around this problem by having the DAC run at a fixed frequency, but keep resampling the input to adjust to it. That resampling logic needs to track the input just the same as the PLL would. So while they show remarkably low jitter performance, they may have other distortions.

Note that all of this talk is about jitter induced by the input stream of audio. There are other sources of jitter that exist inside the DAC itself that are independent of this.

 

[bibo01]

Looking at the number of pool voters, it seems that everybody here is shy

 

[Mike Lavigne]

Man you need better sources than this. His video in this case doesn't really say much, and says some things just wrong. Of course he is the guy claiming in another part of this video that .2 picoseconds of jitter is readily apparent to him. Yeah, right!

so you think you know more about what jitter is than this guy?

really?

I think maybe he knows a bit more on this subject than anyone posting here on this forum. and if he says he can hear .2 picoseconds of jitter, my money is on him being right about that.

 

[esldude]

so you think you know more about what jitter is than this guy?

really?

I think maybe he knows a bit more on this subject than anyone posting here on this forum. and if he says he can hear .2 picoseconds of jitter, my money is on him being right about that.

If it were a betting matter you would have a bet. Whether I know more or less than he I can't say. My comments referred to his comments in the video.

 

[esldude]

Looking at the number of pool voters, it seems that everybody here is shy

Yes, having seen a few of these, and done a couple, you will find people very shy about doing these type things. Making choices with nothing other than their ears to go on seems a bridge too far for many an audiophile.

 

[bibo01]

Yes, having seen a few of these, and done a couple, you will find people very shy about doing these type things. Making choices with nothing other than their ears to go on seems a bridge too far for many an audiophile.

People should enjoy music first and take this hobby as fun.
This pool is supposed to help in both directions. This is not an examination of anybody's ability in listening.
In my view voters, whose name remains undisclosed, should enjoy the result regardless if the outcome matches their vote or not.