[Gibson59]

One thing I’ve found is that using the green filter (incisive neutral with HG roll off) with the USB actually sounds a bit like the optical connection. There are some tracks where I’ve preferred the presence and dynamics of the USB implementation and some others where I’ve preferred the smoothness of the optical. So I may go with USB then just use the green filter when a song calls for it.

I’m loving the filters because their subtle but effective.

 

[Deftone]

I’ve already got an audioquest Carbon optical cable. I’ve been spending time comparing optical to USB connection. I enjoy both but I’m leaning towards USB... sound is bit more dynamic, better instrument separation and the vocals seem a little more forward to which I like. The optical connection has a very smooth presentation and everything is very cohesive, highs feel a touch rolled off by comparison which isn’t necessarily bad.

I’m trying the USB implementation four different ways and getting four different results:

1) USB straight from Mac Mini to Qutest with Qutest stock power.

2) USB straight from Mac Mini to Qutest with iFi iUSB providing the power to Qutest.

3) iFi iUSB between Mac Mini to Qutest with the stock Qutest power.

4) iFi iUSB between Mac Mini to Qutest with iFi iUSB providing the power.

I’m enjoying the experimentation so far. The great thing is each combo sounds wonderful, I just need to determine which sound is my preference. The Qutest is awesome.

Optical is the digital reference but usb is sometimes peoples preferred choice because it has better compatability with higher sample rates 192khz + DSD and the noise from usb artificially gives a more lively sound to set ups that might feel a bit warm.

 

[Gibson59]

Optical is the digital reference but usb is sometimes peoples preferred choice because it has better comparability with sample rates higher and 192 + DSD and the noise from usb artificially gives a more lively sound to set ups that might feel a bit warm.

Not challenging your assertion and I believe I’ve read that on this thread before (by @Rob Watts himself?), but would you mind telling me in laymen’s terms why optical is the digital reference? Is it because of no jitter and no RF noise? I think I understand that RF noise adds some high end, but what on earth is jitter?

To be honest I perceive more of a difference than just a lively sound with USB... soundstage seems bigger and there seems to be more space between instruments, the sound is a little more neutral. Not trying to start a war of optical vs USB, I really am not after trying to crown one as better, I just want to understand the differences from a technical standpoint as to why one may be considered the reference choice.

If I only stream from Qobuz and am not getting anything higher than 192 then I lose out on nothing (aside from perceived sonic differences) if I go with optical right? And the argument for it is I don’t need to add a decrapifier etc in the chain?

Sorry for all the disjointed questions. Any insights are appreciated!

 

[x RELIC x]

Not challenging your assertion and I believe I’ve read that on this thread before (by @Rob Watts himself?), but would you mind telling me in laymen’s terms why optical is the digital reference? Is it because of no jitter and no RF noise? I think I understand that RF noise adds some high end, but what on earth is jitter?

To be honest I perceive more of a difference than just a lively sound with USB... soundstage seems bigger and there seems to be more space between instruments, the sound is a little more neutral. Not trying to start a war of optical vs USB, I really am not after trying to crown one as better, I just want to understand the differences from a technical standpoint as to why one may be considered the reference choice.

If I only stream from Qobuz and am not getting anything higher than 192 then I lose out on nothing (aside from perceived sonic differences) if I go with optical right? And the argument for it is I don’t need to add a decrapifier etc in the chain?

Sorry for all the disjointed questions. Any insights are appreciated!

What you are describing as the differences is exactly what RF noise does to the sound, but it’s false. The common human perception with more brightness is a wider soundstage, more space, more detail, more ‘neutral’. You might prefer it and there’s no right or wrong with your preferences, but, as Rob describes, RF noise causing noise floor modulation is like MSG for audio spicing up the sound. The negative with this is that the sound becomes more flat and depth is reduced and nuance in timbre is reduced. Everything can sound harder. As was mentioned earlier, you can’t add darkness but more brightness is very very likely from RF noise.

Regarding jitter, it’s a timing difference between the source and the DAC and traditionally USB is the best choice for jitter as it’s asynchronous (the timing for the source comes from the DAC), but Rob’s DAC designs are immune to jitter on all inputs so it’s not even a consideration with Chord DACs, unlike many other traditional digital audio gear where optical could have bad jitter.

 

[Arniesb]

What you are describing as the differences is exactly what RF noise does to the sound, but it’s false. The common human perception with more brightness is a wider soundstage, more space, more detail, more ‘neutral’. You might prefer it and there’s no right or wrong with your preferences, but, as Rob describes, RF noise causing noise floor modulation is like MSG for audio spicing up the sound. The negative with this is that the sound becomes more flat and depth is reduced and nuance in timbre is reduced. Everything can sound harder. As was mentioned earlier, you can’t add darkness but more brightness is very very likely from RF noise.

Regarding jitter, it’s a timing difference between the source and the DAC and traditionally USB is the best choice for jitter as it’s asynchronous (the timing for the source comes from the DAC), but Rob’s DAC designs are immune to jitter on all inputs so it’s not even a consideration with Chord DACs, unlike many other traditional digital audio gear where optical could have bad jitter.

If brighter is wider then why All high end dacs, amps sound wider than average dacs, amps? Makes 0 sense. If anything drop in noise floor makes Everything smoother more dynamic and wider. Why does Dave sound much smoother and wider than Hugo 2 for example? Noise makes Everything forward not wide from everything i heard.

 

[x RELIC x]

If brighter is wider then why All high end dacs, amps sound wider than average dacs, amps? Makes 0 sense. If anything drop in noise floor makes Everything smoother more dynamic and wider. Why does Dave sound much smoother and wider than Hugo 2 for example? Noise makes Everything forward not wide from everything i heard.

Might not make sense to you but it does to me. I also didn't say a brighter sound is the only contributor. You can pick apart my perspective/comment but there are many things that contribute to a wide soundstage. I was simply talking about how brightness adds to the perception. You might perceive it as forward, that's fine. I do disagree with you that ALL high end gear has a wider soundstage, let's leave it at that.

Personally, I feel the Hugo2 sounds wider than the DAVE, where I find the DAVE has more depth and a more balanced soundscape. Difference of perspective I guess and I'm not here to argue with anyone.

Typically brighter gear usually has comments that it has a wide soundstage. It's a recurring theme with headphones, amps, DACs. Easy to see the repeated pattern in comments regarding a perceived wide soundstage and bright gear. Not always the case but it's very common.

Besides, we were talking about how the USB input is contributing to the relative differences noted, not comparing different gear. And technically, I would say that the relationship between the highs and mids is more of what causes an overall wide soundstage. You took my reply to someone else out of context though and it doesn't relate to what you've brought up.

 

[Deftone]

Not challenging your assertion and I believe I’ve read that on this thread before (by @Rob Watts himself?), but would you mind telling me in laymen’s terms why optical is the digital reference? Is it because of no jitter and no RF noise? I think I understand that RF noise adds some high end, but what on earth is jitter?

To be honest I perceive more of a difference than just a lively sound with USB... soundstage seems bigger and there seems to be more space between instruments, the sound is a little more neutral. Not trying to start a war of optical vs USB, I really am not after trying to crown one as better, I just want to understand the differences from a technical standpoint as to why one may be considered the reference choice.

If I only stream from Qobuz and am not getting anything higher than 192 then I lose out on nothing (aside from perceived sonic differences) if I go with optical right? And the argument for it is I don’t need to add a decrapifier etc in the chain?

Sorry for all the disjointed questions. Any insights are appreciated!

@x RELIC x gave a good explanation above

Opitical is reference because its completely isolated so it adds nothing at all but its usually avoided because of the problems with jitter but as you can see here from this post by Rob in 2016 about Mojo, its really not a problem. People are spending hundreds of dollars on multiple add on devices trying to get USB galvanicly isolated on the level of optical so if you got a chord dac, spend less than $10 and you wont get better than that (unless you like the noise from USB).

Using an APX555 and the 24 bit J-test file at 48k I get with optical:


There are some asynchronous jitter components just visible at -160dB.

With USB we get:


In this case no asynchronous jitter components as timing comes from the FPGA, but there is some data related components at -150dB. This is due to my very noisy Dell that I use for running the AP. If we were to use a mobile source these components would be much smaller - and eliminated with galvanic isolation.

That said, I do not know of any other non Chord DAC (at any price) that has such low levels of measured jitter from the J-test

Rob

 

[Roybenz]

I have tried jutterbug, cant tell any difference. Rob also answerd me that jitterbug wont work on qutest. Since it already does the same thing as the jitterbug does.

 

[Roybenz]

Anyone know if using audeze dsp in roon will affect the qutest in a negative way?

 

[Deftone]

Anyone know if using audeze dsp in roon will affect the qutest in a negative way?

If it's just a eq preset then no

 

[Deftone]

I have tried jutterbug, cant tell any difference. Rob also answerd me that jitterbug wont work on qutest. Since it already does the same thing as the jitterbug does.

I think jitterbug would be betterbsuited for Hugo 2 because it doesn't have the same isolation as qutest because it would draw too much power for portable use.

 

[Roybenz]

If it's just a eq preset then no

Audeze presets apply carefully designed filters specific to the selected Audeze headphone models. In addition to using our headphones “flat (no EQ)” these filters can be used to provide a listening experience similar to great speakers in a typical well treated room. Additionally, you can tweak these filters by using Roon’s built-in EQ and crossfeed settings. Importantly, each preset has the calibration filters for all commonly used sample rates (44.1kHz to 768kHz) to avoid resampling. Audeze is able to do this because we have our own digital hardware and software engineers, as well as our experience working with Audio Precision in developing headphone-specific test equipment.

Im not sure if its only an eq... hmm

 

[snatex]

Anyone know if using audeze dsp in roon will affect the qutest in a negative way?

Roon upscales from 16 to 64 bit before applying Audeze presets and then back to 32 bit after applying so you might be losing some of the Qutest magic and transparency when using it. Rob recommends sending non altered bit perfect data when possible.

 

[flyte3333]

I had another opportunity to demo the Qutest vs the Hugo 2 for about two hours yesterday with my HEKse/Lazuli Reference. I’m gonna do a longer write-up on the HEKse thread for anyone interested. But my main takeaway is that I absolutely prefer the sound of the Qutest over the Hugo 2. This is whether the Hugo 2 is serving as a DAC/line out only and powered by my Wells Milo amp or with HEKse plugged directly into the Hugo 2 using no external amplification (which many claim is ideal).

I’m still in a bit of shock. After demoing these two against each other a month or two ago and having these same findings I though maybe I was a little nuts. But after this second time demoing them I’m certain about my personal opinion here. IMO if you don’t need portability and you have a good amp than the Qutest is this better sounding DAC... and cheaper! I’m mindful of course that the amp pairing with Qutest is important and my Milo may just have great synergy with it. But either way, it’s a Qutest for me over the Hugo 2 and it’s an easy choice after spending significant time with them on two different occasions in an ideal listening environment.

Hi, was this using the USB inputs of both Qutest and Hugo2?

And Hugo2 plugged into the wall (AC power), or running off it's internal battery only?

Cheers!

 

[Gibson59]

Hi, was this using the USB inputs of both Qutest and Hugo2?

And Hugo2 plugged into the wall (AC power), or running off it's internal battery only?

Cheers!

I was using USB on both Qutest and Hugo 2 and tried both the battery and wall power (desktop mode) for Hugo 2. In each case I preferred Qutest.