Why no transport "slavers" in here?

steveinaz

With all you electronic whiz-kids, does no one pursue slaving a CD transport to your DAC's clock? That seems to be THE best tweak that can be done, to put the final knife in jitters' back. I was reading an article today about it, didn't seem that difficult to do for such a substantial improvement in digital audio.

Class....anyone?

http://www.lessloss.com/page.html?id=41

dkg999

Sometimes a little jitter without slaving can be exciting :twisted:

tonyb

Eh.....the only jitter acceptable to me is a pair of **** bouncing down the street on a sunny afternoon.

Good read Steve.

Face

Asynch USB and I2S address this problem too.

steveinaz

True, but I have never seen a CDP with USB, and I2S is reserved for the MEGAbuck machines.

Face

I2S has trickled down to $2500 servers and $3000 transports, hopefully it'll be even more affordable soon.

agfrost

I believe that the Stello DAC that Ricardo was/is selling has I2S capability, and has a corresponding transport. Price according to the article I read was ~2000 for the pair, IIRC. Not sure if still available new.

steveinaz

This is the DIY'er section, they don't buy no stinkin' pre built stuff in here....LOL

SCompRacer

Steve, have you tried the Soundcheck Touch 3.0 mods mentioned in the other thread yet?

http://soundcheck-audio.blogspot.com/2011/11/touch-toolbox-30.html

heiney9

Did you get it to work Rich? Last thread I read from you was it wouldn't recognize the SQB.

H9

SCompRacer

heiney9 wrote: »

Did you get it to work Rich? Last thread I read from you was it wouldn't recognize the SQB.

H9

After an album played and stopped, the Squeezebox software couldn't find the Touch. Like it went to sleep and wouldn't wake up. While the album was playing, it would find the Touch. I pressed the reset on the Touch which erases the Linux script changes and never tried it again. Besides, I missed not being able to control the volume with my droid (or Controller) and didn't want to carry two remotes around. I left the Media center settings alone so the translation occurs at the 'putie. I got a slight improvement, not night and day though.

steveinaz

SCompRacer wrote: »

Steve, have you tried the Soundcheck Touch 3.0 mods mentioned in the other thread yet?

http://soundcheck-audio.blogspot.com/2011/11/touch-toolbox-30.html

I haven't; I'm pretty satisfied as is, and once my channel island ps arrives I'll see if that will "hem up" my last few minor quips.

CoolJazz

steveinaz wrote: »

With all you electronic whiz-kids, does no one pursue slaving a CD transport to your DAC's clock? That seems to be THE best tweak that can be done, to put the final knife in jitters' back. I was reading an article today about it, didn't seem that difficult to do for such a substantial improvement in digital audio.

Class....anyone?

http://www.lessloss.com/page.html?id=41

That piece seems to suggest the pro setting would be common to see this done. I disagree. The common setup is actually to use a master clock with seperate outputs. Each and every digital device gets it's own clock feed from the master. That's what the typical BNC connector labeled "sync" is. Devices can be set for internal clock or external. All devices slaved to one clock is important and significant. Stand alone devices can use internal clock. Also, each output being independent means if any noise is induced on the line, it only has capability of effecting the one device, not others.

That's not to say this isn't a good mod at all. But routing and use of a well shielded wire would be important so the mod is an enhancement and not a detriment.

CJ

SCompRacer

steveinaz wrote: »

I haven't; I'm pretty satisfied as is, and once my channel island ps arrives I'll see if that will "hem up" my last few minor quips.

Kewl! I've owned some of Dusty's gear. He had a Monolith phono stage that was levels above his CIAudio offering. Matter of fact before ModWright offered his own phono stage he had recommended I get the Monolith. The CIAudio DAC is also great sounding. I had inherited Norm's SB 3 and he had a CI Audio PS with it. I gave it to Victor, and the PS crapped out. Dusty still fixed it for free.

steveinaz

Rich, are you using the USB as an output for digital? I hear this is a BIG step. I've got to re-read on how this is done.

heiney9

steveinaz wrote: »

Rich, are you using the USB as an output for digital? I hear this is a BIG step. I've got to re-read on how this is done.

USB as an output for digital what? On the computer? Why would you use a USB to the Squeeze Box? The USB would go into the DAC and that's assuming the computer is in close proximity to the DAC.

What BIG step up? There are alot more issues using a USB from a computer into a DAC than using an ethernet/wireless SQB.

Maybe I'm missing something, wouldn't be the first time :razz: Are we even still talking about a SQB?

H9

steveinaz

There's a tweak you can do which allows you to change the usb on the Touch to "output" the digital for connection to a usb DAC, rather than act like an input. This is thought to greatly reduce jitter (as compared to spdif)---much like you do in the "slaving" of your transport, talked about above.

In the Stereophile review of the Touch, the reviewer talks about it in more depth---interesting, since my DAC has an unused USB input!

steveinaz

Here you go Brock-- http://forums.slimdevices.com/showthread.php?t=82110

heiney9

See I know I was missing something. Properly done USB is tricky and while I know nothing about the tweak, I'm going to bet it's not implemented very well if it's just software related. USB at minimum needs to be Asyncronous and simply manipulating software probably won't get it done.

I'll have to dig into it to know for sure, but I doubt it's going to be better than the standard way the SQB was designed to be used. But you know this hobby, it's about tinkering and discovering new things. But, I have read extensively about USB transmission since I use a computer in my office rig and it's more complicated to do it properly than plopping a USB port into something.

H9

steveinaz

From Stereophile:

In fact, it was there that I learned that John Swenson, also a contributor to both the Audio Asylum and the Logitech Squeezebox forum, had modified the Touch to allow its USB port, nominally only an input, to output audio. This greatly intrigued me; I had just taken delivery of Ayre Acoustics' new DX-5 universal player, which has DACs and an asynchronous USB input similar to their QB-9 USB DAC, which thrilled Wes Phillips and was Stereophile's 2009 Product of the Year. After tracking down Swenson, I asked him to send me a copy of the instructions for altering changing the Touch's configuration file, which he did, along with a few caveats, warnings, and denials. The tweak is unofficial, and not quite ready for prime time: It defeats all of the Touch's other outputs and recognizes only the specific USB source for which you've configured it. Fortunately, it's reversible by repatching or with a reset of the Touch to factory condition (easily performed with a rear-panel rest button). I forged ahead because . . . well, heck, it was a review sample (footnote 2).

In my opinion, this is the killer app for audiophiles. I'll have more to say about the Ayre DX-5 in a future issue (as will Michael Fremer), but this is relevant to Logitech Squeezebox Touch: it can be part of a state-of-the-art music system. With downloaded hi-def files sent from my PC via the network to the Squeezebox Touch, then to the Ayre DX-5's USB input, I enjoyed two-channel sound that, in my experience, was unsurpassed. It is rumored that the Touch's hardware might even be able to stream 24/176.4 and 24/192 files via USB without downsampling. Although that's a pipe dream, it suggests that the Touch has yet to reveal its full potential. Dare I dream of multichannel?

heiney9

I did read that article when it came out and I don't really believe it's all that killer. Just like a Wadia digital dock with an iPod sounds fantastic according to Stereophile.

http://www.hifi-advice.com/USB-synchronous-asynchronous-info.html

H9

heiney9

http://www.audiophilleo.com/definitions.aspx?Asynchronous%20USB

I say try it and see. I assume your Benchmark is Asynchronous, if it's not don't bother.

H9

FTGV

Back in the first 2ch DAC craze in the 90's a few companies such as Audio Alchemy,Levinson,Sonic Frontiers implemented an IS2 type interface between their transports and DAC's.Unfortunately the SP/DIF was already too ingrained as the de facto standard form of digital data transmision so IS2 did'nt really find many adoptors amongst hi end manufacurers.

steveinaz

heiney9 wrote: »

http://www.audiophilleo.com/definitions.aspx?Asynchronous%20USB

I say try it and see. I assume your Benchmark is Asynchronous, if it's not don't bother.

H9

I can't. I'm chicken.

steveinaz

FTGV wrote: »

Back in the first 2ch DAC craze in the 90's a few companies such as Audio Alchemy,Levinson,Sonic Frontiers implemented an IS2 type interface between their transports and DAC's.Unfortunately the SP/DIF was already too ingrained as the de facto standard form of digital data transmision so IS2 did'nt really find many adoptors amongst hi end manufacurers.

Isn't IS2 an AT&T glass fiber type interface?

Face

I've only seen it as a HDMI cable, but there are other kinds out there.

heiney9

steveinaz wrote: »

I can't. I'm chicken.

Honestly, I don't blame you. I'm not sure the effort/risk is worth the payoff anyway. It sounds damn good as is. If USB was the only option, like with my computer based rig, I'd explore it. I don't discount all the little incremental tweaks that can be performed but I don't have the desire or know how to "hack" for SQB Touch, nor do I really want to.

H9

FTGV

steveinaz wrote: »

Isn't IS2 an AT&T glass fiber type interface?

No,the implementations I refered to used a cable/connector very similar to if not identical to the old S VHS style.

steveinaz

Got'cha. Interesting.

FTGV

heiney9 wrote: »

USB at minimum needs to be Asyncronous and simply manipulating software probably won't get it done.

I don't consider it quite so black and white.While properly implemented Async certainly has the highest potential there are some adaptive mode devices (such as some that use chips like Tenors TE7022L USB reciever) that have been reputed to offer very good sonics aswell.Ofcourse the relative jitter rejection provided by the DAC it feeds will be an important part of the equation.

FTGV

To expound a bit,glass fiber as with coax uses the SPDIF method of combining the clocks and data and sending and recieving them as serial data.The timing errors (jitter)happens during the process of separating the clocks from the data at the recieving end.With I2S the clocks and data lines are kept separate and transmitted as parallel data so no need to separate them thus no timing errors.