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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
audioengr
3,282 posts
 
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
cwlondon OP
1,198 posts
 
Cokorody and Steve N

Thanks for the observations.

Now where do we stand on best execution, please?
audioengr
3,282 posts
 
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
cwlondon OP
1,198 posts
 
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.
mikeyla
14 posts
 
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.
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