[Pricklely Peete]

Quote:

Originally Posted by gevorg /img/forum/go_quote.gif SPDIF is simply inferior to properly implemented USB, especially if you use an internal soundcard. Of course it doesn't mean that SPDIF sucks and if you have a good jitter "immune" DAC like the Benchmark or Ref1, it shouldn't really matter to you since the differences (if any) would probably be insignificant. Kingwa's USB implementations have been based on PCM270x chip, so obviously he found the SPDIF to be superior. Many highend audio manufacturers see that USB audio is the way to go for computer-as-source users. Scroll down in the link below to see what Bel Canto, Empirical Audio, Wavelength Audio, Weiss, Ayre Acoustics, Red Wine Audio, and others have to say about computer-as-source. ca intro

No it isn't inferior. I'm sorry, I have to disagree strongly.

Read the TAS article in August 2009 rag, issue # 194.......

The Article is called "The State of USB Audio" by Alan Taffel.

Alan's experiences mirror my own findings pretty closely.

Peete.

 

[some1x]

What USB implementations did the reviewer test? and what alternatives did he test against? How was his computer setup?

Did the reviewer try the best available USB implementations (including Wavelength/Ayre async DACs, Empirical Off-Ramp I2S with NorthStar, Almarra, dCs Scarlatti etc), on a properly setup PC/MAC, to justify his claim that USB is inferior to SPDIF?

 

[squall343]

The price is pretty steep on this one (US$550 plus shipping)(

Furthermore, usb is still limited by 16/44

 

[gevorg]

Quote:

Originally Posted by Pricklely Peete /img/forum/go_quote.gif No it isn't inferior. I'm sorry, I have to disagree strongly. Read the TAS article in August 2009 rag, issue # 194....... The Article is called "The State of USB Audio" by Alan Taffel. Alan's experiences mirror my own findings pretty closely. Peete.

That article is just an opinion of one reviewer based on subjective listening of several USB dacs. Unlike the Q&A of multiple audiophile manufacturers on Positive Feedack, it does not provide technical explanation of why one way is better than another. Plus the USB dacs in that TAS review did not include dacs from the top manufacturers of highend USB audio, the Wavelength Audio and Empirical Audio. I don't understand how one review can overshadow the findings of major highend manufacturers and many audiophiles who sold their highend CD transports for USB audio.

 

[DoYouRight]

the Ayre QB-9 or Wavelength Cres... have the true 24/96 or 24/192 without drivers and are PHENOMAL and the QB-9 only has usb. Some are not good some are fantastic.

 

[tosehee]

These converters seem to beat the purpose imo. The best way to connect USB is to go straight to DAC through I2s. However, most of these are simply converting USB to SPDIF which we are trying to beat/improve in the first place. Instead of having the timing in the PC and its SC, we are simply moving it to USB Converter..

USB Converter could be equipped with best timing device in the world, but still you can't get the best implementation unless you go straight from USB to DAC.

Am I wrong here?

 

[Lil' Knight]

The QB-9 or Wavelength can do 24/192? I doubt about that.

 

[barleyguy]

Quote:

Originally Posted by gevorg /img/forum/go_quote.gif That article is just an opinion of one reviewer based on subjective listening of several USB dacs. Unlike the Q&A of multiple audiophile manufacturers on Positive Feedack, it does not provide technical explanation of why one way is better than another. Plus the USB dacs in that TAS review did not include dacs from the top manufacturers of highend USB audio, the Wavelength Audio and Empirical Audio. I don't understand how one review can overshadow the findings of major highend manufacturers and many audiophiles who sold their highend CD transports for USB audio.

If you read his forum comments, he requested (and received) a unit from Wavelength, and they would not allow him to test on anything but a Mac Pro with SSD, 16 GB of RAM, and iTunes. He did not believe this fairly represented what most people would listen through, and was planning to test on several different computers and operating systems (as he did with all the other units), which Wavelength would not allow him to do. As a result of Wavelength's unwillingness to be tested in this manner, he sent their unit back.

Maybe Wavelength really is better. But if they refuse to be reviewed without dictating the platform, who is to ever know?

 

[some1x]

I think Gordon actually just requested for his DAC to be tested under a current gen Mac, not necessarily a highly upgraded one like his own.

 

[DoYouRight]

Night my bad didnt mean the 24/192. But it does do the other very well. I thought maybe the wavelength did 192 cant remember.

 

[Pricklely Peete]

The 2 high end DACs reviewed were the brand spanking new Bryston BDA 1 and the Audio Research DA7. This expose isn't just one reviewer's opinion, it's spread over several of them...

Let me pose this question...if USB is able to achieve or even better SPDIF why is it not the no 1 choice of purpose built multi K US music servers ? I don't know anyone who has high end gear and plenty of experience who would even consider USB as option let alone a computer as a serious source. The computer as a music machine has come a long way but it still doesn't better or surpass stand alone gear. It just doesn't. It's not built for audio exclusively...it's like a receiver...it can sound really good but falls short of equaling the best separates. The computer like a receiver is a jack of all trades and a master of none...the USB connection is a jack of all trades, master of none. It really is that simple.


Peete.

 

[tosehee]

Peete.

That's what I thought too, but the recent development on the USB has me wondering if I still have the same mind set about the USB in general. Take a look at the positive-feedback review and the links. Vinnie points out that using the USB fed directly to I2S to their DACs sound even better than 10k DAC system out there.

I believe that the most USB implementation is simply a converter. It connects to the PC and then it converts to SPDIF. It's simply another layer tht provides its own timing. In that regard, it can't rival the best stand alone gears. But, when it's being fed directly to DAC, there is no more SPDIF conversion going on, and the fact that USB has the timestamp, makes the jitter non-issue all together.

I think this is where USB will shine. I could see more and more USB dacs in the future.

Here is the direct quote from Vinnie.

Quote:

It is very clear to me that computer-based audio (i.e., using a computer as the transport for music playback) via the USB port has the potential to sound better than even the best CD transports that output S/PDIF. I have proven this with my own DAC design and many others have as well. Compared to S/PDIF (coax or optical), DACs using the USB can offer significantly lower jitter vs. S/PDIF if implemented properly. For example, our DAC has a USB input that converts the USB data directly to I²S (the native data format fed to the actual d/a converter chip), which eliminates the jitter generated in recovering the clock signal from the S/PDIF data stream.

 

[gevorg]

Quote:

Originally Posted by Pricklely Peete /img/forum/go_quote.gif The 2 high end DACs reviewed were the brand spanking new Bryston BDA 1 and the Audio Research DA7.

Bryston and Audio Reseach are well known to make great DACs, but their USB interfaces are second-rate to their SPDIF interfaces and even limited to 16/44. They don't use the infamous TAS1020B/Centrance that Kingwa cannot afford at this point. There are many high end manufacturers like Bryston and AR who make amazing DACs but have no or little experience in USB audio. Bryston and AR are some of them.

Quote:

Originally Posted by Pricklely Peete /img/forum/go_quote.gif This expose isn't just one reviewer's opinion, it's spread over several of them... Let me pose this question...if USB is able to achieve or even better SPDIF why is it not the no 1 choice of purpose built multi K US music servers ? I don't know anyone who has high end gear and plenty of experience who would even consider USB as option let alone a computer as a serious source. The computer as a music machine has come a long way but it still doesn't better or surpass stand alone gear. It just doesn't. It's not built for audio exclusively...it's like a receiver...it can sound really good but falls short of equaling the best separates. The computer like a receiver is a jack of all trades and a master of none...the USB connection is a jack of all trades, master of none. It really is that simple. Peete.

Peete, I respect your findings that SPDIF sounds better than USB but just by claiming its better does not really tell much. You really need to take a look at the Q&A on Positive Feedback. They go over many technical details discussing USB audio and what makes it superior to SPDIF, there is no point to copy paste it here. In short, the idea of USB audio is that if its properly implemented the audio stream from the source skips the conversion to SPDIF and goes straight to I2S that DAC converts to analog form. The receiving chip/DAC "slaves" this transfer making the source jitter irrelevant (which is called the asynchronous mode). On the other side, if a given DAC has good anti-jitter measures then it won't really matter if you use USB or SPDIF (like in your case since you have Ref1's DSP-1).

 

[tosehee]

Ref'1 DSP-1 has a good anti-jitter measures, but not jitter free. I would think that USB -> I2S -> DAC would still be better if Kingwa provides such option in the future. Granted, he needs a proper USB implementation in the first place..

 

[gevorg]

Quote:

Originally Posted by tosehee /img/forum/go_quote.gif Ref'1 DSP-1 has a good anti-jitter measures, but not jitter free. I would think that USB -> I2S -> DAC would still be better if Kingwa provides such option in the future. Granted, he needs a proper USB implementation in the first place..

In theory you're right, but what if DSP-1's jitter is below audible levels? Sooner or later that threshold will be reached, if not already.