Up to the Minute: Streaming Bits to Audiophile DAC


I have some unanswered questions from another thread, and also some new ones despite searching the archives. So I hope this thread might be a good place for all of us who are interested in state of the art audio quality from hard disk drive based files.

Kublakhan in another thread suggested using the Sweetwater Creation Stations as hardware for a PC based audio solution and so far this gear looks pretty good to me.

My questions, however, arise from the fact that there may be some disconnect between the conventions for "pro audio" and "audiophile" audio.

So as of this writing, can anyone please explain:

Why does every pro audio person seem confused when I tell them I want to use an external DAC?

What is the BEST way to extract bit for bit data from a hard drive, to export to an audiophile DAC?

Why oh why do expensive $$$ music or media servers, which are supposedly configured to optimize audio use, nonetheless require some sort of cheapo "interface" to stream the data into an audiophile DAC?

Why on earth would I want to buy an audiophile "sound card", which I presume (in addition to an "interface") also has its own DAC?

Given the options which are available for "sound card" and/or "interface" type devices, what is the BEST way to tap the bitstream and/or maximize performance of the audiophile DAC? Optical? TOSLINK? Spdif?

Given the choices I might have for the "interface" between the computer and the DAC, what is the BEST way to minimized "jitter" or other audiophile nasties? Or is that phenomenon more of a downstream issue AFTER the bitstream hits the DAC?

There is a lot of great information in the other threads about ripping, tagging, Foobar vs Itunes and a million other complications of hard drive based audio.

But for now, I would really appreciate just some basic, conclusive opinions on the best way to get bits off the hard drive and safely on their way to my speakers from an audiophile DAC.

Please advise.

THANK YOU.
cwlondon
Good questions. One persons opinion. From the top:

Pro audio people don't see DACs as playback devices. They seem them as a way to get digital into the analogue world and onto their master tapes - I think... Very important to distinguish between true high-end studios and prosumers where most of the action is.

Best ways to export are USB and Ethernet.

Streaming the bits does not require all that much - the whole thing is all about decoding/reconstituting them. Up to that point all you need to do is deliver the bits - something every computer in the world does every day.

No known reason on earth to buy a soundcard. Definitely not recommended. You want to get the bits away from the electronic nastiness that is a computer before you make waves.

Optical=toslink. The best is I2S but almost no DAC manufacturers uses it. Look at the Empirical Audio website for a lot of good info.

IMHO the number one source of jitter is the least then perfect CD transport/player. Simply to hard to solve all the opto-electic-mechanical problems without spending megabux. Ripping to HD eliminates the transport as a problem.

Next, getting the data out of the computer eliminates the computer as a source of electrical/ground problems. Things like the Opticis USB cable provide a very high degree of isolation from the computer electronics.

Poor SPDIF / Toslink implementation is the next source of trouble. Not quite such a big deal. Good implementations are around - true 75ohms etc. I2S makes those problems go away.

IMHO the two SOTA solutions are USB to an I2S DAC, and a modified Squeezebox.
From my fairly limited experience, I agree Ckorody's thoughts.

Depending upon your budget, hardware, and needs, I believe an outboard USB DAC is the way to go.

I was in your boat a few months ago, and recently acquired a USB DAC -- the Wavelength Brick. After the fact, I can honestly say that this is one of the most prudent decisions that I've made during my many years in this hobby.

I divested myself of a $6K CDP ($8K if it had outputs; transport & DAC were identical).

My primary front end is a turntable, so CD playback is for media not available on vinyl, or simply for convenience. And PC audio is convenience PLUS! For the few weeks I’ve had the DAC, I’ve had more fun than I would have imagined – playing more varied music as the mood strikes me, than I ever thought possible!

Because of vinyl, my goal was to improve music access, and if the USB DAC didn’t quite achieve the same level of reproduction as my CDP, I wouldn’t have minded. But much to my surprise, the opposite was true. Absolutely wonderful sonics; I believe better than before, with the added bonus of supreme convenience!

Believe it or not, the computer I originally used was an ancient PII 300mghz, with a 160GB HD.

State of the art hardware is absolutely overkill! However, depending upon how you plan to configure you system, silence IS important.

I have since bought a MacBook because of the funds I had left over after my CDP sale and the DAC purchase. Getting a multifunction PC (laptop), plus a music server, was the incentive, and this was my first non-Windoz based machine. So far, I love it.

Yep, there has been a learning curve for both the hardware and software components of my transition. However, this old dog finds learning new tricks to be fun.

Gordon Rankin’s Wavelength Audio website has some very helpful information about PC audio – take a peek if you haven’t already done so.

Lastly, if you’re going to use a Windoz based PC, your media player and hardware configuration is important. You need to bypass Windoz K-mixer. ASIO and plugins will help you do so with a player like Foobar. The same is true for J River’s Media Center, however, the plugins are built-in and less difficult to acquire and install.

On the other hand, if you have an Apple and iTunes, just plug ‘er in and let ‘er go.

I hope this helps…..
The best digital connectivity solutions are (best to worst):

I2S
AES/EBU
S/PDIF
Toslink

I2S DAC's include:

Perpetual P-3A
Benchmark DAC-1 (with mods)
Northstar 192
Lite Dac-60 (with mods)
Now that a few more months have passed....

could anyone please update this thread on experiences you have had streaming digital bits to an audiophile quality DAC?

In the end, I decided to not buy the Sweetwater Creation station:

one sweetwater rep suggested it wouldnt make a great all around PC

still, it would require an "interface" to get the data stream into a DAC

any new ideas, please?

any new candidates for I2S DACs?
Have you considered an evaluation board DAC? Crystal Semi and Analog Devices (among others) offer them at reasonable prices - add a low noise PSU (batteries or soft recovery diodes etc) and you're away. Most have a digital direct input for I2S. You can mod the output stage for transformers (eg Lundahl microphone type) or tubes as you see fit if you don't like transistors...

Then build up a USB to I2S convertor - such as one at www.dddac.de and you're away.

I've done the above on an AD1896 eval board and it works just great.

Cheers, Kendrick
Kpavey wrote:
"Then build up a USB to I2S convertor - such as one at www.dddac.de and you're away."

I looked at this design. I uses the PCM2707 TI chip. This means that it can only use the Windows drivers and will not pass 24/96. IMO, this chip is only useful for Wi-Fi, which is already limited to 16/44.1 and does not require any driver because it is networked. For USB, you need a non-windows driver to get good sound quality.

Steve N.
Jitter is dependant on the last out device to the DAC. How the DAC handles the jitter depends on the build quality. Bits are bits, period. Whether SPDIF or Toslink does not matter to the DAC. If there is electrical interference, that is a different ball game. If you are concerned about noise from the PC, you can put a ferrite core on the cable to the sound card. Use a Toslink or SPDIF cable to the DAC. That should eliminate the interference problem for the majority of users. The Red Book standard is 44.1 and the upsampling can be done with the external DAC. My Tri Vista 21 samples 96/192. Bit perfect output via my Chaintec 710 card has been verified by me. Foobar kernel streaming bypasses Windows Kmixer, as well as ASIO drivers. No need to get expensive sound cards, unless you are using the onboard DAC's from the card itself. Otherwise the external DAC is useless when using analog output from the sound card. Foobar is free and quite easy to set up. It is convienient when playing music, as it is all in front of you with just a click away.

PC built by me.
Tri Vista 21 DAC
Toslink connection
Levinson Pre
Levinson 33H Mono Blocks
Genesis 201 4 column speakers w/ 1000 watt Amp
SDI modded Apex DVD player and Sampo firmware
2 Ehome 8500 CRT's blended

One hell of a setup that sounds and looks fantastic.

MAK
MAK

Finally, someone is making a lot of sense - thank you.

Could you give more detail, please on how we get the bits from the PC to the DAC without using a soundcard.

An "interface"(?) What connections, cables etc could I order when building my own PC?

What is the cost no object, best audiophile solution to then use the external DAC of your choice?
racerxnet wrote:
"If you are concerned about noise from the PC, you can put a ferrite core on the cable to the sound card. Use a Toslink or SPDIF cable to the DAC. That should eliminate the interference problem for the majority of users."

This technique will certainly attenuate HF noise from the computer, however it will actually make the jitter worse. It will slow the risetimes of the S/PDIF or AES signal edges and cause the receiver to switch at less accurate/predictable times as a result.

The best solution is to isolate the digital conversion and final clocking from the computer completely. This way, the jitter can be made extremely low. Either USB or Wi-Fi accomplishes this.

Steve N.
Empirical Audio
Manufacturer
Cwlondon,

I never looked into using a USB device or any other regarding the output to the DAC. There is no need when a capable card is able to output a bit perfect stream. With Foobar or an ASIO plugin you have eliminated the Kmixer in a windows based system. I am using a Chaintech 710 card which costs about $27.00 at the local computer shop. I output using a custom optic cable from Fiberfin. This goes to the digital lens which eliminates all jitter and then to the Tri Vista.

If your the you chose has a buffer it should be able to stabilize the jitter timing and provide the rich satisfying music we all strive for. As for the choice of DAC's, there are many which cost much and sound mediocre. Let your ears decide what you like best.

Building a PC is quite simple and straight forward. Just be sure to get a case which allows room to route the cabling. Most full size ATX boards with PCI-E are going to do the job without breaking a sweat. Your choice of AMD or Intel. If you are using the PC as a HTPC the get the fastest processor you can afford. This is where horsepower will pay off when decoding HD content.. especially when running ffdshow.
"This goes to the digital lens which eliminates all jitter and then to the Tri Vista."

I'm sorry, but this is "wishful thinking". The only de-jitter device that I've seen to be really effective is the Apogee Big-Ben, and even this is not as good as what you can get with a USB converter IME. Even this does not eliminate "all jitter", nothing does.

Steve N.
Empirical Audio
Manufacturer
Quit your whining and show some proof that the jitter is still present. I guess Arnie and gang is is a fool for creating such a product. Several write ups confirm that the jitter is reduced consideralby, to the point of nil. If you are hawking your own product, I'm not convinced it is better than what I have currently. Other than that I'll continue to measure with my equiptment and evaluate with my ears. As a software engineer I am aware of the limitations from electronic devices.

Best of Luck Steve
Racerxnet

What "measurements" do you take? The software engineering kind??

The digital lens certainly does not remove "all" jitter....especially something with as much as jitter as the Chaintech.

jdubs
Pricey like hell but the Zanden DAC uses IS2 if I recall correctly
Well the increasingly heated debate here suggest to me that this puzzle still isn't solved.

I am still frustrated and confused as to why we cant export bit perfect WAV files from a well built custom computer into an audiophile DAC and otherwise FORGET all these cheapo sound cards, crap power supplies, jitter inducing processes and arcane acronyms built that I associate with mass produced plastic computers.

As this is supposed to be an "up to the minute" thread...please do continue.

Anyone?

Does the Benchmark DAC work well for this now? Or does it need "mods"? WHy does it need "mods"?

Is the Zanden "pricey like hell" because it is some weird tweako hand made limited production voodoo product and/or one of the few in the world that happens to have IS2?

Are the bigger manufacturers of DACs not listening? Why wouldnt every DAC maker in town be thinking that the world is starting to use hard drives for music and maybe it might be worth a second thought and the extra 50 cents to add an IS2 output to their 5 figure high margin DACs?

I rarely like digital music of any kind, so this set up is more for convenience and archival purposes than trying to outperform my Rockport reference turntable.

Again, if anyone knows how to export a WAV file bit stream into a reasonably priced decent performing DAC without a lot of extra steps and garbage, either electronically or scientifically, or placing a special order to some garage manufacturer who never answers his phone, please let us know.

Cheers

Cwlondon
Well the increasingly heated debate here suggest to me that this puzzle still isn't solved.

I am still frustrated and confused as to why we cant export bit perfect WAV files from a well built custom computer into an audiophile DAC and otherwise FORGET all these cheapo sound cards, crap power supplies, jitter inducing processes and arcane acronyms that I associate with mass produced plastic computers.

As this is supposed to be an "up to the minute" thread...please do continue.

Anyone?

Does the Benchmark DAC work well for this now? Or does it need "mods"? WHy does it need "mods"?

Is the Zanden "pricey like hell" because it is some weird tweako hand made limited production voodoo product and/or one of the few in the world that happens to have IS2?

Are the bigger manufacturers of DACs not listening? Why wouldnt every DAC maker in town be thinking that the world is starting to use hard drives for music and maybe it might be worth a second thought and the extra 50 cents to add an IS2 input to their 5 figure high margin DACs?

I rarely like digital music of any kind, so this set up is more for convenience and archival purposes than trying to outperform my Rockport reference turntable.

Again, if anyone knows how to export a WAV file bit stream into a reasonably priced decent performing DAC without a lot of extra steps and garbage, either electronically or scientifically, or placing a special order to some garage manufacturer who never answers his phone, please let us know.

Cheers

Cwlondon
As to why the industry is not responding - now there is a million dollar question...

Given that every level of the consumer electronics business (in which for this purpose I include our noble pursuit) are constantly looking for the next great thing to stimuate sales, you would think that at the very least these kinds of capabilities would make for a fine line extension.

One can only assume that the old guard and its customers are computer illiterate (which is a somewhat generational phenom) and that everyone else is trying to figure out how to hitch their wagon to the iPod shooting star...
I put up a long post answering this, but it seems to have dissappeared....

The short answer is that most manufacturers dont know how to design this and they are also afraid of starting a new I2S standard. Of the few that are doing USB interfaces on DAC's only a couple know what chips to use for best sound and some even put S/PDIF in the middle because they evidently dont know how I2S works.

Steve N.
Empirical Audio
Manufacturer
Cokorody and Steve N

Thanks for the observations.

Now where do we stand on best execution, please?
Best execution. Well, I'm of course biased because I build these things, but contrary to popular belief, it is possible to build a world-class I2S interface that is external for both Wi-Fi and USB. However, there can also be advantages to burying it in the DAC.

Best Execution is probably USB to I2S currently because the chips are just better, particularly the TAS1020A and the TUSB3200 from TI. Wi-Fi does not perform as well due to the 270X chipset. Wi-Fi is also limited to 16/44.1. The best results from these chips requires a good custom S/W driver. The PC drivers are just not any good, so far. Chips like the 270X series work with the native PC drivers, but they sound crappy IMO.

Chips aside, the implementation of the USB interface, clocking and the I2S interface is critical to getting low-jitter results. The circuit design is critical to getting no pops or DC out of the DAC when the power or USB cable is pulled. This is why most designers cannot pull-off external I2S. It's tricky.

Steve N.
Empirical Audio
Manufacturer
Can anyone please give a quick, up to the minute update on streaming bits to an audiophile DAC?

Yesterday, I took a trip to BH Photo in New York which is always an adventure.

Their "Pro Audio" guy on staff came highly recommended and for the first minute or so seemed like he knew exactly what he was talking about when it came to hard drive based audio and uncompressed, bit for bit WAV files.

As we spoke, he pointed me towards a glass case full of reasonably expensive pro audio DACs, and also the Benchmark DAC 1 in a sleek, black rack mountable case, in stock for $995.

Unfortunately, it was all downhill from there, however, and he then had ABSOLUTELY NO IDEA how I would

1) rip my CDs to WAV files on the hard drive(s) of my choice

2) "tag" these WAV files with album and track information

3) export bit for bit perfect data without insulting my other components by using a cheesey cheap sound card or "interface"

4) implement "best execution" for connections, whether USB, XLR or some other acronym that I dont necessarily understand

and

5) Get all of this with a minimum amount of "jitter" or other nasty artifacts into the DAC of my choice.

From the DAC, I can handle things from there.

This guy looked at my like I was nuts, and even more so when I told him this was for only 2 (?!?!?) channels, despite his credentials as a Benchmark dealer.

So I am still confused and would greatly appreciate any up to the minute updates on this lively, timely topic.

Steve N I appreciate your technical comments, which may also be a bit over my head.

Could anyone put together an off the shelf list of components that I can go out and buy today to do this in a Windows environment?

Thank you.
I'll give it a shot. Here is what I'm doing, and by no means am I an expert - started less than a year ago.

My setup from the bottom up, PS Audio P500 for power, Accustic Arts MKIII DAC, SinglePower Supra Headphone Amp and Sony Qualia 010 headphones.

I use iTunes for Windows sending wireless digital data (Ethernet) to a WiFi OffRamp with battery supply (this is a modded Airport Express, with superclock 4 etc...) which is connected to the RCA input of the Accustic Arts DAC. I’ve also used a stock Airport Express toslink connection to a Monarchy DIP Upsampler (to reduce jitter) then BNC to the DAC. This also sounded very good, but I haven’t really sat down to perform an A/B test. I could also be the Accustic Arts DAC is forgiving when it comes to transports – I don’t know.

I rip CD's using a Plextor PX-716UF USB external drive. It's my understanding the ripping process is the important piece. Plextor drives seem to have a good reputation. I upgraded to the PlexTools Professional XL software to rip CD's. I rip to WAV files with error-correction set to the highest level. I don’t believe WAV files have tags. I then make a copy of the WAV files and convert this copy to Apple Lossless using dBpower Amp Music Converter and then use Tag&Rename to retrieve tag information and CD art.

iTunes is set not to copy files when importing. All the Apple Lossless files are in one folder. I tell iTunes to import from that folder and within seconds the new tagged songs appear in the music library ready to play.

Foobar for playback and EAC for ripping are two open source programs that seem to have a strong following and good reputation, but their setups were a bit to complex for me.
I'll give it a shot too:
1) rip my CDs to WAV files on the hard drive(s) of my choice

I have found that the fast DVD-R/W drives in Toshiba laptops work great with Exact Audio Copy. They do error-free rips at 5-8X speed. This is extremely important. I purchased a Sony laptop with what I thought was a decent DVD drive only to find that it would only rip at 1X. This takes 45 minutes to an hour to rip a single CD. I returned it immediately.

2) "tag" these WAV files with album and track information

EAC has functions that you select that automatically retrieve the data from FREEDB database on the web.

3) export bit for bit perfect data without insulting my other components by using a cheesey cheap sound card or "interface"

This is tricky. There are a lot of soundcards out there and most of them have high jitter outputs. The lowest jitter will come from external independently powered converters, the best being I2S, followed by a well-implemented AES and then S/PDIF interface. The best sound comes from USB converters that use custom software drivers, not Windows drivers IMO. I would not recommend ANY internal PCI sound card.

4) implement "best execution" for connections, whether USB, XLR or some other acronym that I dont necessarily understand

Avoiding S/PDIF or "digital coax" is best if you are wanting USB conversion. USB conversion supports higher sample rates, such as 24/88.2 and 24/96. Wireless "Wi-Fi" does not support anything other than 16/44.1, but can be easier to set-up and has the wireless convenience. Wi-Fi can also sound great.

and

5) Get all of this with a minimum amount of "jitter" or other nasty artifacts into the DAC of my choice.

Again, the design and clock quality is key to obtaining the best result.

I would give you the list of components, but this would be advertising.

Steve N.
Empirical Audio
"Wireless "Wi-Fi" does not support anything other than 16/44.1, but can be easier to set-up and has the wireless convenience."

The SD Transporter can do 24/96.
Kana813 - Are you certain that the transporter does 24/96 wirelessly? I could not find this in the specs.

Steve N.
"Are you certain that the transporter does 24/96 wirelessly? I could not find this in the specs."

Steve N- do a search for 24/96 on SD's forum, you'll see
a number of Transporter owners report it works.
If this is true, sounds like a good one to mod.

Steve N.

Check here for the Digital Outputs and Inputs.

Amongst other things:

Sample rates: 44.1kHz, 48kHz, 96kHz
Audio format: linear PCM, 16 or 24 bits per sample
Fun thread. Anyone want to bite on how you are doing this with an Apple G5?

Also, I see referances to streaming audio, but I am of the opinion that most internet music does not have all that much information that requires more than a decent toslink connection. Am I wrong?
Unclejeff - the term streaming also refers to what the computer does when it sends the data to the converter at the native rate.

My customers tell me that 24/96 upsampling on MAC is not as good as native 16/44.1 As for PC, there are several upsamplers that can be used with Foobar2000. Some sound great.
Jamscience - yes I read all of this. Does not specify whether this is supported wirelessly. You can direct internet wire to the box also.
"If this is true, sounds like a good one to mod."

Steve N.- MauiMods.com/Aberdeen is already doing mods on the Transporter.
Kana813 - when it comes to mods, I have very little competition. I have such a backlog (12 weeks) that I am turning most of them away now. I dont see any info on the website about the nature of the Transporter mods BTW..

Steve N.
Steve N- I've never heard your work, but I'll put my money on Mauimods.com/Aberdeen or APLHIFI. The mauimods.com Transporter mods are new, so he has updated his website yet. Anyone that's interested, should contact Anthony directly for more information.
I want to do this with MY OWN DAC.

Need help. Please continue.
If you want to use your own stock DAC, then the best solutions IMO are S/PDIF interfaces with low jitter, such as the modded Squeezebox3 from Bolder or Red Wine with a good Digital cable (wireless and limited to 16/44.1) or Empirical Audio Off-Ramp Turbo 2 (USB interface), which comes with a captive S/PDIF cable (will do 24/96).

Steve N.
Empirical Audio
Manufacturer
Kana813 - you can spend your own money any way you want, it's your money. BTW, are there any reviews of the Maui mods?

Steve N.
"BTW, are there any reviews of the Maui mods?"

Steve N.- search mauimods/aberdeen on audiocircle or
the tact users forums.

Steve N.

This answer from Christopher Owens at SD should resolve your question:

"I did test 24/96 before we shipped, BUT I don't have a lot of test content in 24/96 formats.

I expect there are some 24/96 tracks that don't play due to oddities in the formats that the firmware or software decoders don't understand.

So, don't be reluctant to file a bug if you run across such a track! I'm happy to check it out.
__________________
Christopher Owens
QA Manager
chris@slimdevices.com
(650) 210-9400 x717 "

The main point of my post was of the assumption that it would since the Transporter uses 802G wireless. (54Mb/s capability vs. 4.608Mb/s for streaming 24/96) I understand your concerns. You can stream 24/96 by either ethernet or wireless. (although it looks as if there are still a few bugs in the wireless implementation)
I wanted to post a quick update. I'm sending the WiFi-OffRamp to Steve for a minor mod and had to setup the Airport Express / Monarchy DIP as a transport. This gave me a chance to perform a little a/b comparison.

The WiFi-OffRamp definitely sounded better. I'm not familiar with all the audiophile terms, but there is definitely a notable difference, better bass, instrument separation and sound stage.
The Sims people are having an open house this Friday which will be my opportunity to check out the Transporter. Does anyone have more thoughts on this equipment?

Belkin announced today the Cable-Free USB Hub (F5U301) will be shipping in Mid-December for $199.99.

It is capable of speeds up to 480Mbps with a range of 30ft.

Check out the press release here.
For those still curious... about how a music lover goes all the way from taking out his favorite CD, to having a digital file come from his computer and out through his audiophile system... read on.

The simplist way I have found has been to insert the disc into my CD drive on my computer with iTune's preferences for automatic import on insert: Apple Lossless with error correction "on."

On insert iTunes automatically looks up the track information and performs all the tagging. iTunes also downloads the cover art. if it is available.

So far, so good... now the digital files are in my searchable and well-organized (not to mention slick-looking) itunes library, taking up about half the space they would if not compressed. (Some people prefer the open-source "flac" compression, but for me, itune's ease of importing and its integration with podcasts and my ipod make itunes my favorite.

Now the files are on my good old computer, a Macintosh G4 400, nothing fancy necessary here, speed is not necessary, only lots of hard drive space. I installed two new 160gb seagate baracudas chosen for their low noise characteristics (now I wish they were at least twice that size). In the hard drive preferences I set them up to be a mirrored pair, so if one goes out, everything is exactly the same on the other. No backing up!

As for listening... after considering my options:
Computer soundcard (noisy)
Airport (not guite audiophile)
Inexpensive external USB converter (remote control?)
Expensive external USB converter (expensive!)

I chose Slimdevices Squeezebox 3 for the following features benefits:
WIRELESS SECURE CONNECTION (802.11 b and g) with my computer (now in the other room! I like that. And now, should I decide that I would like another Squeezebox in the house, the SB3 acts as a wireless bridge, extending the range of my wireless capability. The Squeezebox also connects equally as well with your everyday household ethernet cable.
REMOTE VOLUME CONTROL which also lets browse and search and play my entire music library, play randomly, or from iTunes playlists... oh, the power!
INTERNET RADIO ACCESS with the computer on (or off!)
DIGITAL OUTS s/dif and optical for my external DAC
AUDIO OUTPUTS which are quite decent sounding, though somewhat compressed
MARVELOUS READOUT adjustable in size, brightness, scrolling speed etc.

If this set-up doesn't sound quite tweaky enough, buy Slimdevices Transporter, and get all the connectivity in the world, plus professional standards like AES/EBU, and word clock, so all your digital devices can march to the same drummer.

With word-clock, (and the addition of a master-clock and compatible DAC, digital amp, or digital speakers) the home audiophile can put the kabosh on the sonic artifacts of interconnect generated jitter once and for all (the way the studios have been doing it for years). I feel calmer already

"With word-clock, (and the addition of a master-clock and compatible DAC, digital amp, or digital speakers) the home audiophile can put the kabosh on the sonic artifacts of interconnect generated jitter once and for all (the way the studios have been doing it for years)."

Sounds good, but the reality is that noone that I am aware of has made the word-clock work yet. The fact is, most modern consumer DAC's, such as the Benchmark DAC-1 use D/A chips that perform the D/A using the bit-clock, not the word clock. No improvement in the word-clock will make any difference at all. It's the bit-clock or master clock that need to be low jitter, not the word-clock.

Steve N.
Empirical Audio
Manufacturer
http://cachepe.zzounds.com/media/quality,85/brand,zzounds/UCA202_big-c5c66c5ee06b3a89a1fe3b25a7ba0cb3.jpg

Can anyone guess what this interface does?

I still dont understand how I can plug a cheap device into my USB port and it somehow knows if I want to extract an analogue signal or stream bits.

Would the optical output stream bits?

In the case of an analogue signal (for example, the headphone output) would this thing look through to the DAC in my Sony VAIO laptop, or would it also have its own cheap DAC thrown in for the low low price of 30 bucks?

I started to write a new thread - "Streaming Bits for Dummies" but thought I should continue here.....

For the most part, I am still clueless.

Thank you.
I believe this device is very similar to the M-Audio Transit, but it probably uses the PCM270X chips instead and no software driver. Unlike the Transit, it would be limited to 48kHz.

You could get digital S/PDIF output from it just like the Transit from the optical output. Like the Transit, it uses a cheap clock inside, so very jittery I suspect.

There is also a D/A and an A/D inside, so you get analog outputs. Like the Transit, the power supply on this comes from the 5VDC off the USB cable which orginates at the computer. You can guess how clean this power is.....
Hi Steve and thanks.

* So this thing will output SPDIF, but only through an optical output which is not best execution?

* Furthermore it is limited to 48khz?

* And the whole set up will be prone to jitter?

* And whatever problems you would also get from a cheap and noisy power supply?

Sounds like we are still in the dark ages for streaming bits to an audiophile DAC?
CWlondon - No, we are not in the dark ages, you are just looking in the wrong places IMO.

Steve N.
I agree with Steve. We are NOT at all in the dark ages with this. As with many
things in audio, there is a range of devices that will accomplish the same task
but to varying degrees of quality. You can spend anywhere from $40 - $1400 on
a USB to SPDIF converter. You can also decide to spend anywhere from $50 to
$5000 or so on a USB capable DAC.

You must decide on what you want to do with your digital front end. I will take
delivery tomorrow of one of Steve's Offramp Turbo 2's which is a USB to SPDIF
converter. I have been expirmenting with these devices for almost 2 years now. I
really like my DAC so that is why I am committed to having a converter of this
sort. If I did not already have a DAC I really enjoyed though, I would probably be
trying to audition some of the USB capable DAC's.