Wiim Ultra with external DAC: what output?

Vignus

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I'm using Wiim Ultra with an external DAC (Gustard) and I would like to hear you guys opinion on what output sounds better: coax, optical or USB?

I know it really boils down to personal taste, but I'm still very curious about your findings. Can you share?
 
I'm using Wiim Ultra with an external DAC (Gustard) and I would like to hear you guys opinion on what output sounds better: coax, optical or USB?

I know it really boils down to personal taste, but I'm still very curious about your findings. Can you share?
Connect all 3 then you make a switch from wiim ultra audio out. From here you can compare which sounds that you prefer. Every listener is different. Some say usb, some say coax. Let your ear decide from here.
 
Even though my DAC only processes at 24/48 for USB, the resulting music is smoother and more harmonious than when using Coaxial or Optical at its higher 24/192 input resolution. The difference is especially noticeable with treble frequencies both initially and also without 'fatigue' during long listening sessions - in many ways digital replay sounds extremely similar to the same music from my vinyl collection.

Maybe 'this' DAC 'clock' is fractionally out of sync when using the other two inputs, possibly because adaptive asynchronous* USB circuits can operate faster than synchronous circuits because they don't have to wait for a global clock pulse to begin processing inputs & can also minimize clock skew between the two devices.

*Adaptive isochronous is used in this DAC for USB because it is time sensitive, as is music. Pure asynchronous isn't necessarily time sensitive & data retries can introduce glitches or stop-start playback. 48kHz is the original professional digital audio tape resolution and as much of my music playback is analogue I am comfortable with this as the maximum resolution for my digital files and streamed music.

As others suggest, as everything is 'personal' in this hobby I would also recommend trying each digital output into the external DAC to decide which suits (as well as RCA line-output, bypassing an external DAC because the DAC in the Ultra is reputed to be excellent in its own right and clocking issues should be minimised).
 
I'm using Wiim Ultra with an external DAC (Gustard) and I would like to hear you guys opinion on what output sounds better: coax, optical or USB?

I know it really boils down to personal taste, but I'm still very curious about your findings. Can you share?
With my Rega dac R - without question the best sound is with coaxial spdif . Next best is asynkron USB. Slightly worse = toslink.

One has to try what sounds best with different dacs, because its entirely depending on the specific dac.

Using my Mac M1 through USB to Rega dac R sounds worse than using the Ultra as digital transport.
 
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With my Rega R dac - without question the best sound is with coaxial spdif . Next best is asynkron USB. Worse = toslink.

One has to try what sounds best with different dacs, because its entirely depending on the specific dac.
Just curious, why is there a difference in sound between Toslink and Coax? It is exactly the same digital signal (SPDIF) with same timing.
 
Just curious, why is there a difference in sound between Toslink and Coax? It is exactly the same digital signal (SPDIF) with same timing.
Yes it should be - maybe the coaxial spdif input on the Rega is more colored with more RFi making the sound slightly different and I like the sound of that ?
 
Yes it should be - maybe the coaxial spdif input on the Rega is more colored with more RFi making the sound slightly different and I like the sound of that ?
Ok, but it doesn't make sense except if the interface are connected to different DSP/DAC circuits and analog stages.
With same DAC and filtering all should sound the same as it is same data.
 
Ok, but it doesn't make sense except if the interface are connected to different DSP/DAC circuits and analog stages.
With same DAC and filtering all should sound the same as it is same data.
RFi can colour the analog stage of the dac , making it sound slightly brighter. Im not saying its the case though, but it might be. Toslink dont have that issue.

You can do an experiment , as I did. Make a RCA cable without shielding and compare it to a cable with good shielding. The cable without shielding will sound clearly brighter . Thats RFi in its glory. You might even like the sound of it, givning extra artificial details to the sound.

Now, you might argue that RFi in digital transmission dont make any difference. It does, because it will infect the whole dac including the analog stage. RFi is very hard to get rid of. Toslink is the best transmission interface on a technical level.

This is good teaching:

 
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So with your Rega dac R the best sound is with the connection that is most prone to noise? If you really think that the optical connection is the worst you probably have a bad cable or connector.
 
So with your Rega dac R the best sound is with the connection that is most prone to noise? If you really think that the optical connection is the worst you probably have a bad cable or connector.
No, I use the original toslink WiiM cable . The Rega dac R always sounds best with coaxial spdif , also with my Yamaha wxc50 used as streamer . But the Rega has a colored sound that I like.

The WiiM ultra is a better sounding streamer than Yamaha wxc50 , by the way. Used as transports.

You have to understand that ” technically perfect” is not always the same as ”best sounding”. We humans like colorations and the stereosystem is a very primitive one - in need for some colour. The technically superior toslink lacks any RFi colour. It is better than asynkron usb connection with less noise.

So, which output from the Ultra should one use then ?

The one that sounds the best with the specific dac used.
 
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Anyway, as already written, use the one that sounds better to you. All this talk about coloring is just a way to say what kind of noise and distortion is added to the original signal.
 
Anyway, as already written, use the one that sounds better to you. All this talk about coloring is just a way to say what kind of noise and distortion is added to the original signal.
Indeed, not everyone is same. Some people that transparent is too polite and want to color the sound. All personal preference.
 
When I owned a Wiim Pro I used Coax, it had smoother sibilance.
With my Wiim Ultra I could not notice a difference between Optical and Coax, unfortunately both sound ”sharper” (more sibilance) than my Pro did.
I use active speakers from Dali, wirelessly connected to Dali Sound Hub that connects to my Wiim for streaming.
 
Have any of you who connected an external DAC encountered a situation where, in the case of an SPDIF connection (both optical and coaxial), in the high frequency range you could hear some artifacts, distortions, or irregular hissing? They cannot be heard from a distance, but they are clearly audible up close. In the case of a USB connection, this does not happen. I also connected another source (CD player) via spdif to rule out a problem with the DAC and here the sound is absolutely clear.
 
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