[Viper2001]

Quote:

Would there be any improvement in SQ to be had by wrapping the D2's transformers in mu-metal? Inquiring minds want to know. Thanks and regards

 
Probably too little to be noticeable.  You would be better off upgrading the clocks on U2.  That would bring substantial improvements.

 

[Sapientiam]

Which clocks' replacement would bring substantial improvements? ISTM its using the ESS sample rate conversion built into the chip, which is fairly universally said to sound worse than running the DAC synchronously.

 

[hionhifi]

Has anybody compared the Anedio to the Peachtree iDAC? The Anedio does cost more, but have a little bit different feature set. I prefer the feature set of the Anedio, but a good deal ont he iDAC had me carting one home from the dealer! 

 

[Viper2001]

Quote:

Which clocks' replacement would bring substantial improvements? ISTM its using the ESS sample rate conversion built into the chip, which is fairly universally said to sound worse than running the DAC synchronously.

 
The two clocks on the U2 board.  They largely determine the output jitter of U2.  And D2's sound can still improve quite significantly if its S/PDIF input is fed with a lower jitter S/PDIF signal.
 
Which DACs are running ESS9018 in synchronous mode?  Even Invicta is running ESS9018 asynchronously,

 

[Sapientiam]

So it seems you are saying that ESS's touted jitter reduction techniques don't work very well. Which isn't
particularly surprising.
 
Here's one thread where synchronous mode is being discussed - the implementation in question is Buffalo2.
 
http://www.diyaudio.com/forums/digital-line-level/117238-ess-sabre-reference-dac-8-channel-39.html
 
Just thinking out loud, ISTM it would make more sense to slave the oscillators on U2 to the master clock on D2 and run in sync mode. But that's a fairly major mod - would require a PLL on U2. Then D2's clock would be the jitter determinant.

 

[veritas aurum]

Quote:

 
The two clocks on the U2 board.  They largely determine the output jitter of U2.  And D2's sound can still improve quite significantly if its S/PDIF input is fed with a lower jitter S/PDIF signal.
 
Which DACs are running ESS9018 in synchronous mode?  Even Invicta is running ESS9018 asynchronously,

It just may be that we are more sensative to jitter than previously thought. Regards

 

[Sapientiam]

Yes it may be so. On the other hand it might not be jitter that's being heard but could be the effect of common-mode noise as listening tests done for jitter demonstrate we are remarkably insensitive to it. This is not conclusive as the jitter listening tests are normally done with uncorrelated jitter.

 

[veritas aurum]

As Von Recklenhausen said "If it measures poorly and sounds good, you are measuring the wrong thing". Or the converse, I really can"t remember. A sign of age. Regards

 

[Viper2001]

Quote:

Yes it may be so. On the other hand it might not be jitter that's being heard but could be the effect of common-mode noise as listening tests done for jitter demonstrate we are remarkably insensitive to it. This is not conclusive as the jitter listening tests are normally done with uncorrelated jitter.

 
If jitter is fairly high, you'll hear bright and harsh sound, and music is not engaging.  But when jitter is reasonably low, most people will hear music with good PRAT and lots of details.  But they have no idea how the music will sound when jitter is extremely low.
 
At the extreme level, it is not jitter artifacts you hear per se, it is what you missed that was present in the recordings.  The extremely low jitter transport will sound more analog, with better instrument separation, darker background, faster transients and attacks, more micro details, more liquid mid and treble, more hall sound/reverbs, and holographic sound stage.  And one of the toughest things with digital reproduction is better weight (body) in mid and upper bass, IOW, high tone density and more refine tonality and shades.
 
Basically, it gives you the feeling of being there.  That's what an extremely low jitter transport can do.

 

[veritas aurum]

I agree with Viper. I was enjoying my D2 fed by my cheap Tascam CD200. When I added the Audio-gd DI, subtle nuances that I had not heard before suddenly were clearly audible. All the things cited by Viper. Regards

 

[ishmael]

Quote:

YES!  SB Touch with Enhanced Digital Output to D2 is the BEST sounding setup I've heard.  I think Project86 should find a SBT to evaluate his D2.
 

 
So whatever happened to this? 20 something pages ago the USB input was praised as the best way to experience the D2. Now it is being considered sub-par, compromised, etc by the very same people. I don't get it.
 
Viper, if I may ask: do you feel that there is any limit at all to the audibility of jitter? In other words, how low is low enough, before it stops being an issue? I'm sure you are aware that the limited research in this field indicates an audibility threshold far higher than what we typically deal with in higher end audio gear. 
 
I guess I'm just lost as to why we are spending so much time focused on this one issue, when problems like room acoustics are orders of magnitude larger. Or in your case, using the admittedly good but somewhat lower end SR407 rather than the 007 or 009. 
 
Oh and btw the guy from ART Legato is clearly in violation of the HeadFi rules by posting here without becoming a MoT. No major harm done because he isn't really trying to sell us his product (since Viper is already doing that for him) but I suggest he stop before causing problems. 

 

[Sapientiam]

Quote:

 
If jitter is fairly high, you'll hear bright and harsh sound, and music is not engaging.  But when jitter is reasonably low, most people will hear music with good PRAT and lots of details.  But they have no idea how the music will sound when jitter is extremely low.
 
At the extreme level, it is not jitter artifacts you hear per se, it is what you missed that was present in the recordings.  The extremely low jitter transport will sound more analog, with better instrument separation, darker background, faster transients and attacks, more micro details, more liquid mid and treble, more hall sound/reverbs, and holographic sound stage.  And one of the toughest thing with digital reproduction is better weight (body) in mid and upper bass, IOW, high tone density and more refine tonality and shades.
 
Basically, it gives you the feeling of being there.  That's what an extremely low jitter transport can do.

 
I have fairly high jitter in my current (totally DIY'd) system. Its easily bad enough to see on my oscilloscope so that means its probably at least 1nS, maybe more.I don't though have a bright and harsh sound, quite the opposite - its addictive and really draws me in. So I remain a jitter skeptic.
 
What I have found causes a bright and harsh sound is noise. I've eliminated noise from my system as that was fatiguing and made me wanna turn it off after even just a couple of CDs.

 

[ishmael]

Quote:

 
I have fairly high jitter in my current (totally DIY'd) system. Its easily bad enough to see on my oscilloscope so that means its probably at least 1nS, maybe more.I don't though have a bright and harsh sound, quite the opposite - its addictive and really draws me in. So I remain a jitter skeptic.
 
What I have found causes a bright and harsh sound is noise. I've eliminated noise from my system as that was fatiguing and made me wanna turn it off after even just a couple of CDs.

 
What a refreshing approach. That makes sense to me because you are going after something you enjoy rather than adding more boxes to chase down a jitter gremlin that hasn't even been proven to exist.
 
Is it just me, or has anyone else noticed that usb to spdif converters almost always sound better to people? Even when the DAC being used already has extreme jitter reduction, and even when the D to D converter is not all that great such as the various hiface units, which actually measure pretty poorly in jitter according to audiophilleo. That makes me think that people just like adding magical boxes to their systems no matter what. Especially if it involved adding an extra high end cable to the chain. 

 

[Sapientiam]

Quote:

 
What a refreshing approach. That makes sense to me because you are going after something you enjoy rather than adding more boxes to chase down a jitter gremlin that hasn't even been proven to exist.
 
Is it just me, or has anyone else noticed that usb to spdif converters almost always sound better to people? Even when the DAC being used already has extreme jitter reduction, and even when the D to D converter is not all that great such as the various hiface units, which actually measure pretty poorly in jitter according to audiophilleo. That makes me think that people just like adding magical boxes to their systems no matter what. Especially if it involved adding an extra high end cable to the chain. 

 
Thanks for your encouragement. I started my journey to DIY audio nirvana about 3 years ago, attacking the more obvious defects in my system, which appeared on certain recordings - mainly on female vocals. I have yet to attack jitter - its just not the 'low hanging fruit' of audio. Perhaps I won't even bother with jitter reduction - we shall see.
 
The problems I can see with the various USB inputs of DACs are to do with noise, rather than jitter - specifically noise coming from PCs and contaminating the grounds inside DACs. This happens because USB inputs are often an afterthought and bought in as OEM boards, rather than fully engineered within the main DAC PCB. Using an external USB-SPDIF converter means that the noise problem is largely eliminated - no additional noise gets added to the DAC's internal (analogue) ground. But it could be fixed by correct grounding inside the DAC, ensuring that noisy digital grounds do not mix with analogue grounds.

 

[LeoDuran]

So whatever happened to this? 20 something pages ago the USB input was praised as the best way to experience the D2. Now it is being considered sub-par, compromised, etc by the very same people. I don't get it.

Well, although the (SBT+EDO) front-end has been consistently held in high regard, what has been discussed is that the D2's USB implementaion does have shortcomings.

That is, you may still use (SBT+EDO) over Async USB; but optimal results may be achieved by going from there to a low-jitter USB-to-SPDIF converter: feeding D2 via SPDIF, rather than using the D2's USB input.

HTH