[Viper2001]

Quote:

 
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. 

 
Don't get discouraged by what we discussed in the last few pages.  Like Project86 was saying, some people like myself are chasing the very last bit of performance of D2.
 
D2 by itself sounds very good on USB input compare to driving it with an average transport via S/PDIF coax.  It is just that I managed to drive it with a better transport and achieved better results.
 
I think jitter needs to be in the femto second range before it stops completely being an issue.  But that also depends on the playback chain, the type of music and the listener.  I'm sure not everyone can hear the differences down to the femto second level.  I don't claim to have better hearing, it's just that I found live classical recordings more revealing than other types of music.
 
Surely, room acoustics plays a much larger role than the last bit offered by devices like the Legato.  But with headphones, the improvement of a better transport can be heard quite clearly.  My SR407 Signature is not low end.  The main difference b/w different Stax HPs is tonal balance.  The higher end units have meatier mid-range and bass.  Then there is the issue of HPA, which also has a lot of influence in sound.  My SRM-T1 does sound better than 006t or SRM-1/Mk II by quite a bit.  It has the speed like the solid state SRM-1/Mk II, yet a liquid mid-range like tube.
 
Finally, I do happen to know the guy at AR-T.  I asked a lot of questions about the Legato since the beginning of this year before I finally decided to buy one.  I ordered the Legato around the same time I ordered the D2.  And I waited 4 months for my Legato built.
 
In any case, I've no financial interest with any Legato sales.  I happen to like this product, and I also have a pre-order with the Legato II.

 

[yfei]

Right now the only thing between D2 and my ears is HD 580 headphone. 
To my ears, if scale of the sound difference between a good computer sound card to D2 (PC->USB->D2) is 1.0, then the sound difference between (PC->USB->D2) and (SBT+EDO->D2) is 2.0 or 3.0!    It's hard for me to believe by reducing jitter then difference can be that huge!
 
Has any one using equipment to measure the difference between stock SBT and SBT+EDO?   e.g. if is still bit perfect? what's difference in jitter?   or everyone are objective, only using ears to measure?
 
(and SBT+EDO->D2 still sounds too harsh for me.  i'll get another SBT to see if mine is defective)
 
Quote:

With (SBT+EDO), the front-end of your system will be more revealing... I hate to sound like a "snub", but now it's time to pay attention to the back-end of your system (between the D2 and your ears)... any weaknesses threre will be more glaring.
Good luck.

 

[LeoDuran]

Quote:

Right now the only thing between D2 and my ears is HD 580 headphone. 
To my ears, if scale of the sound difference between a good computer sound card to D2 (PC->USB->D2) is 1.0, then the sound difference between (PC->USB->D2) and (SBT+EDO->D2) is 2.0 or 3.0!    It's hard for me to believe by reducing jitter then difference can be that huge!
 
Has any one using equipment to measure the difference between stock SBT and SBT+EDO?    or everyone are objective, only using ears to measure?
 
(and SBT+EDO->D2 still sounds too harsh for me.  i'll get another SBT to see if mine is defective)
 
Quote:

I'm not sure I understand what you mean by 1.0 vs 2.0, etc...
That is: Does PC->USB->D2 sound better for you than (SBT+EDO)->USB->D2?
 
I don't know what kind of measurements would solve the riddle for you... So trust your ears, and go with whatever you like best!

 

[yfei]

the scale of difference, i meant the 'total amount of difference' in the sound.    Including both what I like and what I don't like,  the total differences.
 
If the total difference from good PC sound card to D2 is 1.0     (D2 is certainly better in every aspect)
Then from PC->D2 to SBT+EDO -> D2, the total sound difference is 2.0~3.0,   including both good difference and bad difference.   The later is cleaner, better resolution, better spatial resolution, but highs are harsh, fatigue, clinical.
 
 
Quote:

I'm not sure I understand what you mean by 1.0 vs 2.0, etc...
That is: Does PC->USB->D2 sound better for you than (SBT+EDO)->USB->D2?
 
I don't know what kind of measurements would solve the riddle for you... So trust your ears, and go with whatever you like best!

 

[Duckman]

Wonder if it's possible to stick one of these in the D2. It is said to be very good.

 

[LeoDuran]

Quote:

the scale of difference, i meant the 'total amount of difference' in the sound.    Including both what I like and what I don't like,  the total differences.
 
If the total difference from good PC sound card to D2 is 1.0     (D2 is certainly better in every aspect)
Then from PC->D2 to SBT+EDO -> D2, the total sound difference is 2.0~3.0,   including both good difference and bad difference.   The later is cleaner, better resolution, better spatial resolution, but highs are harsh, fatigue, clinical.
 
 

I see... ummh...
1) Have you tried different headphones?
2) Have you tried bypassing the internal U2? That is, have you tried (SBT+EDO)->SPDIF->D2?
(cable is imporatnt with SPDIF, so may try RCA or TOSSLINK depending on best cable)
 
Good luck.

 

[Viper2001]

My custom U2 clock mod.  Works on the first try.  44.1K clock for now.  So far the mid-range/upper bass is meatier.  Will cook it for a few days and see how I like it

 

 

 

[tme110]

wow
 

 

[Viper2001]

44.1K and 48K clocks installed now.  I also tapped the signals for turning the clocks on and off, so when I play redbook material, the 48K clock is disabled and vice versa.
 
So far I like what I hear.  The improvement seems to be greater with redbook playback.
 

 

[LeoDuran]

Quote:

44.1K and 48K clocks installed now.  I also tapped the signals for turning the clocks on and off, so when I play redbook material, the 48K clock is disabled and vice versa.
 

Good show Viper.
 
Regarding the Crystek oscillators: I was wondering how you get from 22.5792MHz to 44.1KHz, and from 24.576MHz to 48KHz?
I suspect the answer has to do with the other components on the board (L1, C1, L2, C2 & R1).Thanks for the explanation.
http://www.crystek.com/crystal/spec-sheets/clock/CCHD-957.pdf
 
BTW, how is the modified U2 comparing to the external Legato?

 

[Viper2001]

Quote:

Good show Viper.
 
Regarding the Crystek oscillators: I was wondering how you get from 22.5792MHz to 44.1KHz, and from 24.576MHz to 48KHz?
I suspect the answer has to do with the other components on the board (L1, C1, L2, C2 & R1).Thanks for the explanation.
http://www.crystek.com/crystal/spec-sheets/clock/CCHD-957.pdf
 
BTW, how is the modified U2 comparing to the external Legato?

 
Actually, my circuit does not do the division.  I'm merely replacing the original Pierce oscillators with Crystek of the same freq.  The oscillators are used to "reclock" the S/PDIF signal from the XMOS chip.  Reclocking reduces the jitter on the U2's output.
 
The sound is really wonderfully good.  Much more organic and natural.  Transients and attacks are even faster.  I think now it should be on par with MSB DAC on that front.
 
Next week, I shall bring it to my friend's place and have another shootout with his MSB DAC

 

[LeoDuran]

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.

Without a doubt, galvanic isolation to eliminate noise from the source is key, but timing (clocking) is also important.
Here's an interesting article on: "How does jitter sound?"
http://www.jitter.de/english/soundfr.html
 
Less jitter" sounds better, much better!
Auditioners testified:
* improved ease of listening
* increased clarity
* improved high frequency response
* better instrument separation
* more information
* better timing
* better soundstage
* improved overall audio performance
 
--EDIT-- DISCLAIMER:
I realize that the topic of "jitter" can be as controversial as "global warming"... So, please take the quoted article as information, not gospel (I am by no means an expert on the subject).

 

[SoupRKnowva]

Quote:

44.1K and 48K clocks installed now.  I also tapped the signals for turning the clocks on and off, so when I play redbook material, the 48K clock is disabled and vice versa.
 
So far I like what I hear.  The improvement seems to be greater with redbook playback.
 

 
So when're you gonna start your Anedio D2 modding business?   

 

[Sapientiam]

Quote:

--EDIT-- DISCLAIMER:
I realize that the topic of "jitter" can be as controversial as "global warming"... So, please take the quoted article as information, not gospel (I am by no means an expert on the subject).

 
Thanks - I'm already aware of the work of Charles Altmann. I agree its unwise to take what listeners report as gospel.
 
Isolation of a DAC from noise sources is far more important than jitter in my experience. The noise sources to watch
out for are the mains supply itself, and PCs. The average DAC has a connection to both. Galvanic isolation most
certainly can help a lot but the isolation is not complete at high frequencies, so its more important to know the
capacitance across the isolation barrier than know whether the isolation is of the 'galvanic' kind, or not.
 
If you look at the pics Viper2001 has posted of his D2, you'll see that it has a 'block' type mains filter (top left). In
my experience these aren't really adequate in taming mains-borne noise. It also shows a toroidal type mains
transformer (the blue thing with fins, bottom left). Designers keen to reduce mains noise don't use such trafos - a
good example is the extremely well regarded Berkeley Alpha DAC. Its transformers look positively pre-historic in
comparison with this one, but they've been chosen for good reason - isolation. Toroids have the two windings
(primary - mains, secondary - low voltage) wound over the top of each other. This means high interwinding
capacitance - an open window to mains noise.
 
If I was a D2 owner (and I wouldn't buy because I'm a multibit addict, not S-D) then I'd be looking into optimizing the
noise immunity before the clocking. That's not to say the clocking is unimportant, just getting the priorities right.

 

[Riker]

Just to be crystal clear, if I run a signal to my D2, (via Sonos) but without the pre/pro and amp turned on, it is still considered as " burn in " ?
 
I've been running my Sonos 24x7 for 12 days straight to the D2, with about 2 hours of actual listening via pre/pro + amp + speakers every day.
 
Doing the math, I am assuming that I have put 288 hours of "burn in" on my D2.
 
Is that correct ?
 
Or is burn in only when it's actualy playing through my speakers ?
 
 
Thanks
Riker