Jump to content

The $500 jitter challenge


Guest Old Man Rubber

Recommended Posts

Guest Old Man Rubber

I will donate $500 to StereoNet if somebody here who believes they can hear jitter,  using the following setup:

 

1.  Two different CD transports of my choosing.

2.  Two DACS, one of which can be built into either the amplifier or the CD player.

3.  Level matched and quickly switchable, playing two identical CDs.  Levels to be matched using an SPL meter.

4.  Any levels of jitter to be measured on both systems  before the test is started.

 

The challenger must be able to do better than chance in picking differences between the two systems.

 

 

I will send the CD player(s) to an independent facility (i.e. an accommodating hi-fi store).  One of the CD transports can be of the challengers choosing but at least one must be supplied by me, and the make/model of said player not to be revealed until the test is over.

 

 

Link to comment
Share on other sites



Guest Old Man Rubber
1 minute ago, Andythiing said:

To what end?

To make a small attempt to put the whole nonsense argument about digital transports and jitter to bed.

Link to comment
Share on other sites

23 minutes ago, Old Man Rubber said:

I will donate $500 to StereoNet if somebody here who believes they can hear jitter,  using the following setup:

 

1.  Two different CD transports of my choosing.

2.  Two DACS, one of which can be built into either the amplifier or the CD player.

3.  Level matched and quickly switchable, playing two identical CDs.  Levels to be matched using an SPL meter.

4.  Any levels of jitter to be measured on both systems  before the test is started.

 

The challenger must be able to do better than chance in picking differences between the two systems.

 

 

I will send the CD player(s) to an independent facility (i.e. an accommodating hi-fi store).  One of the CD transports can be of the challengers choosing but at least one must be supplied by me, and the make/model of said player not to be revealed until the test is over.

 

Why are there two DACs?  (or have I misunderstood something?)

 

DACs have differing abilities to reject certain types of jitter.    So an identical digital signal into two deferent DACs can produce different outputs.   That is flaw one.... there needs to be only one DAC.

 

A second flaw in the test is that if the challenger can supply a player.... they can supply a player which is modified to produce an insanely high jitter spectrum.... that will make a DAC produce quite obvious distortion.    So the test would be too easy to pass under this circumstance.

 

Another "flaw" (is it a flaw, I dunno) is that depending on the DAC chosen, it might reject all reasonable amounts of jitter.   The "flaw" being that failing this test does not "prove" that jitter is always irrelevant.   The combination of source and DAC is important.

 

Another issue is that while the most obvious and objectionable forms of jitter sound like "harsh noise over a flat lifeless sound" (ie.  significant intermodulation of the noise floor) ...... the hardest to get rid of forms of it (a what high typical end stuff is focussed on dealing with) is phase noise that has a very low frequency.   This affect quite low audio frequencies the most ..... and affects the "dimensionality" and "soundstage" .... and "3d ness"  (anyone would think I don't hate audiophile terminology, LOL).    IME a hifi store would NOT be the place to be able to hear that.    High quality bass response is hard enough to get right in a dedicated, high end setup/room.

 

 

<shrug>

 

  • Like 2
Link to comment
Share on other sites



20 minutes ago, Old Man Rubber said:

To make a small attempt to put the whole nonsense argument about digital transports and jitter to bed.

Most people are fine with a reasonable quality CD transport.... and reasonably well engineered DAC.

 

 

As I said in the other thread though.

 

"it depends on how well the DAC rejects the jitter".

 

 

Can I just get away with buying a cheap shotty $30 DVD player???  ......  into a DAC with poor reclocking and jitter rejection??? .... is going to measure bad and sound bad.

Link to comment
Share on other sites

Guest Old Man Rubber
54 minutes ago, davewantsmoore said:

Most people are fine with a reasonable quality CD transport.... and reasonably well engineered DAC.

 

 

As I said in the other thread though.

 

"it depends on how well the DAC rejects the jitter".

 

 

Can I just get away with buying a cheap shotty $30 DVD player???  ......  into a DAC with poor reclocking and jitter rejection??? .... is going to measure bad and sound bad.

 

Yes you can.

 

In fact, I will happily supply said $5 DVD player from the tip shop.

54 minutes ago, rantan said:

 

Oh puh-leeeeze.

 

Why do we want more windmills at which to tilt and accomplish nothing except another circular argument.

 

Jitter is measurable and audible ( in many cases )

 

Nut up, or shut up.

Link to comment
Share on other sites



Guest Old Man Rubber
1 minute ago, davewantsmoore said:

Cool.   I'll supply the DAC then?

 

You'd better bring ear plugs... it won't be nice. ;)

I don't have to be there, just somebody independent who is happy to keep score.  Just give me a shipping address and don't look at the transport before the test.

 

The transport might  only have coaxial SPDIF depending on what I pull out if that matters, otherwise it will be a CD player with optical out.  The one with optical and coaxial might have cost me $7.50 I will have to check.

Link to comment
Share on other sites



  • Volunteer
1 hour ago, rantan said:

 

Oh puh-leeeeze.

 

Why do we want more windmills at which to tilt and accomplish nothing except another circular argument.

 

Jitter is measurable and audible ( in many cases )

 

 

1 hour ago, Batty said:

Yawn

 

1 hour ago, rantan said:

Indeed.

 

I prefer watching paint dry.


As with all threads, particularly those in the great debate section, if you don’t like them, there is no obligation to participate. 
 

  • Like 4
  • Thanks 1
Link to comment
Share on other sites

2 minutes ago, sir sanders zingmore said:


As with all threads, particularly those in the great debate section, if you don’t like them, there is no obligation to participate. 
 

 

Yes, but first one must inform everybody of one’s non-participation.

  • Like 1
  • Haha 10
Link to comment
Share on other sites

Guest Old Man Rubber
6 minutes ago, brodricj said:

Let's not try flog this dead horse back to life.

 

From the Oracle of digital audio jitter.

I love how all these self appointed experts completely ignore error correction and buffering and talk about a bit stream as if it was an analog signal.

 

I'm very glad they aren't working in other technology fields though, so perhaps the audio woo industry does have a function in that it keeps all the crazies away from the important stuff.

Link to comment
Share on other sites



13 minutes ago, Old Man Rubber said:

I love how all these self appointed experts completely ignore error correction and buffering and talk about a bit stream as if it was an analog signal.

 

I'm very glad they aren't working in other technology fields though, so perhaps the audio woo industry does have a function in that it keeps all the crazies away from the important stuff.

 

I love how self appointed gurus with an overinflated self-importance and only half a clue but think they know the whole shebang proceed to demonstrate their ignorance to a global audience.

  • Like 1
Link to comment
Share on other sites

16 minutes ago, Old Man Rubber said:

...and talk about a bit stream as if it was an analog signal.

 

Are you forgetting that digital bitstreams are just analog voltages being rapidly flip flopped between two different states? And there is a finite rise time between the change of state, and there are timing variables in detecting the change of state, there is phase noise of the clock that is at the heart of every digital audio system, and all sorts of other physics happening that all add up to "bits aren't bits".

Link to comment
Share on other sites

21 hours ago, Old Man Rubber said:

2.  Two DACS, one of which can be built into either the amplifier or the CD player.

 

There could be an issue with that because of the relatively low sample rate of CDs, and the fact that the top octave leading up the Nyquist frequency can be filtered in different ways that are audible (depending on the parameters chosen in the design of the reconstruction filter), albeit that such differences would be subtle and might not be noticed in casual listening. This is a quite separate issue to any jitter that might or might not be present.

 

This is less of a issue with a sample rate of 48kHz, which a lot of modern devices use instead of 44.1kHz.

 

Edited by MLXXX
Link to comment
Share on other sites



  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...
To Top