Different solutions to usb input

[barrows]

On 11/4/2020 at 7:56 PM, OldBigEars said:

The Optical input is said to be the best of its inputs

Who told you that???

 

The USB input is the best input on the Qutest.  An opticalRendu combined with a Sonore Power Supply would be a significant upgrade over your µR v1.4.  Do not believe the nonsense about USB being "flawed" in some ways, like any input though, it will respond with better sound quality with a better source and cable (same is true for any other input in a DAC).

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7 hours ago, Blake said:

the designer Rob Watts says this input on the Qutest is the best. 

When Rob Watts says this, he is referring to comparing USB input fed from a standard commercial computer, not from an audiophile grade USB source, the results of this comparison would be much different if the USB source had a high quality output (ultra low noise power feed, ultra clean data feed with high signal integrity).  Source matters here.

[barrows]

28 minutes ago, OldBigEars said:

His views are not really a question of speculation, though you argue he doesn’t know his own product as well as others do, I guess.

Of course they are.  Note all of the users who report an increase in performance of the Qutest DAC with a high quality linear power supply, even though Rob Watts denies that such a change would make any difference.

 

The point being, the USB source matters.  If one just connects the output of an ordinary laptop computer to a DAC via USB, a ton of noise will come over that connection to the DAC (yes, I have measured this), and in the case of the Mojo, it will also result in a ground loop in most cases (I have a Mojo here and have noted this).  So if one is using an ordinary laptop as a source, the isolation provided by the toslink connection can be an advantage, and this is what Rob Watts is talking about.  But if one is using a high quality USB source, with a clean output (in terms of both noise and USB signal integrity) such as a Sonore Renderer, USB will outperform toslink every time, unless the USB input in the DAC is horrendously bad (and I do not find the Chord USB implementations to be that bad).

 

I would advise people to test this in their own systems, and not take Rob Watts' comments for granted, especially considering he is not talking about using a high quality USB source.

[barrows]

3 minutes ago, MarkusBarkus said:

...didn't Mr. Watts also say streaming from your phone was about as good as it gets? Not finding the link at the moment. 
 

FWIW: the Qutest sounded much better here on a Farad3 than their SMPS. And the DAVE sounds much better with that goofy 14 dollar SMPS removed and external cabling to a DC4. 
 

Hey Barrows, maybe wrong thread, but big thanks for mentioning the Iconoclast ICs. Just plugged them in and they are sweet. Mark

Yeah, Iconoclast does not have the rest they deserve, yet...  Pretty fantastic cabling regardless of price.  It is kind of funny, if they put some fancy connectors on their 4x4 OCC XLR cable, and charged $10K for 4' pair, I bet everybody would be all over tham and the accolades would be coming in right and left!

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5 minutes ago, OldBigEars said:

possibly a Sonore Rendu, or something even better

I am not guessing, I am a fan of Rob Watts' work, and I have read many of the threads which you are referring to, including ones where he has recommended the optical input on various Chord DACs.

 

I am nearly certain that no one from Chord or Rob Watts himself has sampled a Sonore Renderer, we at Sonore would almost certainly be aware of that.  I have never even heard of him using a Networked audio set up?  From the threads I have read where he participates, it appears that a very large percentage of his listening is headphone based with a Hugo 2 and M Scaler, of course I am sure that not all his listening is that way.

 

But I will emphasize, that despite the copious amount of time he contributes to forums (head fi specifically), I have never heard him mention using a source other than a standard commercial computer.  I think it is pretty reasonable to think his comparisons of USB vs. Toslink are via a standard computer only, especially considering the outcome.

 

Again, I encourage users to try the different inputs themselves, and decide for themselves which inputs work the best in their system, in their application, and not just take another person's word for it, whether that other person is Rob Watts, or myself.