[JaMo]

@JaMo Thank you for the impressions on adding an external clock to your DCCs. It's very helpful! I'm also very interested in adding an external clock in the future. I've heard a user over at CAM, who had added the Mutec SE120 to their two Mutec MC3+ USB ddc units connected in series and the sound quality improvements for that individual were massive. He mentioned it was similar to jumping from a low end dac to a high end dac. He can't stress enough of how important it is to improve one's system clock. According to your ratings, the DI20HE seems to benefit the most from the Mutec SE120? Just curious, were you using usb or coax input on your DI20HE? Can you expand a little on the night and day difference of adding the Mutec SE120 to the ddc, especially the Di20HE? Do you feel there's improvement in timing of music, clarity, imaging, air, & soundstage?

Hi, my values at the end of my writing are how I think they perform compared to each other and to my preferences (of course..)
They all benefit very much on adding the REF10 as a master clock. The MC3+USB uses a switched PSU when You buy it and I removed that instantly and added an Ultra Silent LPS with a "buffer cap-compound" inside it between +5V and Gnd. That made it smoother but like in them all, (DI20HE, U18, MC3+USB) the clarity and laid back, completely effortless presentation, appears when You add the Master clock. You will get a soundscape where You can spot all the details with ease. The scene will be wider, deeper and higher and the precision, in good recordings, where the instruments are located will also be easy to spot. The layering leaves no secrets as well. The presentation well be "calmer and clearer". If You are to buy one go as high as You can afford (AfterDark have good ones for decent money). I think a high quality master clock is a wise investment if You have ambitions to go towards higher end sound reproduction. More and more digital gears will be equipped with master clock inputs. The legacy is from the studio area, where Pro recording equipment have been using them a long time. For us HiFi nerds it is a home run use them.. But You have to go for the better XO's from let say: -116 dB/1Hz and lower, to get the real "performnce lift"

What I have been saying is that the U18 answers very well on the added master clock and with it, it punches well over its pricetag.

The DI20 is on a true high end level and is as Kingwa usually does things, he overengineers without any compromises. I salut him for that. The DI20HE is without any doubt, the best. But I think it is pretty astonishing that the U18 does "9.5" for me. The MC3+USB is also good after my treats. I can without any hesitation recommend the DI20HE and the U18.

Save up to a good master clock.
/Jan

 

[801evan]

Fortunately measurements has zero correlation to sound quality and performance. Many have posted how the u18 and the di20he is the top two performers.

 

[tamahome77]

@JaMo Thank you very much for expanding your impressions in describing in detail the benefits of adding an external clock. It's important to know which areas of sound quality the clock would improve as the higher end ones are pretty expensive. Appreciate the invaluable info and recommendations provided. This will surely help me decide which clock to get in order to attain worthwhile sound improvement.

 

[Researcher]

All guys here say that measurements do not influence overall sound quality. I wholeheartedly accept this statement for 'digital-analogue products' up to a point. However, this is a digital-to-digital converter. The job of it is simply 'jitter' and 'electrical noise', both of which can be measured. If a DDC fails at those, it should not be recommended. This is because it does not do what is intended to be. U18 does not fail at all but does not compete well with many DDCs out there. No buy from me

 

[MartinWT]

All guys here say that measurements do not influence overall sound quality.

Not me. I say we don't measure the right things that correlate with sound quality.

Shame as the U18 is a great product for sound quality.

 

[kumar402]

All guys here say that measurements do not influence overall sound quality. I wholeheartedly accept this statement for 'digital-analogue products' up to a point. However, this is a digital-to-digital converter. The job of it is simply 'jitter' and 'electrical noise', both of which can be measured. If a DDC fails at those, it should not be recommended. This is because it does not do what is intended to be. U18 does not fail at all but does not compete well with many DDCs out there. No buy from me

What according to you is correct jitter and noise value that DDC should at least have ? The absolute value that you see for U18 is it below that recommended value ?
When one amp has SNR of 120 and one has 105 does it mean 105 is bad or both are good as above certain value it doesn’t matter

 

[Researcher]

What according to you is correct jitter and noise value that DDC should at least have ? The absolute value that you see for U18 is it below that recommended value ?
When one amp has SNR of 120 and one has 105 does it mean 105 is bad or both are good as above certain value it doesn’t matter

Amp is analogue. I talked about DDCs which are all about digital. Let's consider; A DDC has a jitter of around 500ps while another one has a jitter of 75ps. This matters, I believe. Moreover, if You can buy a better DDC for less, or a much better nearly-noise-free DDC for a couple of 100 USD more. I do not think U18 deserves half a thousand USD. On the other hand, It appears that using a single iPhone to DAC as a streamer makes much less electrical noise to the circuit.

 

[MartinWT]

You are not understanding the total jitter and phase noise along the digital chain. You cannot take the U18's figures in isolation: an external clock, grounding boxes and low noise power supplies make a great deal of difference.

 

[ihyan2]

I am expecting delivery of the u18
Plan to use it after the Lumin u1 mini ( usb) and then I2S out to Rockna wavedream.

Which pin out settings can be used for Rockna?

Thanks

 

[Researcher]

You are not understanding the total jitter and phase noise along the digital chain. You cannot take the U18's figures in isolation: an external clock, grounding boxes and low noise power supplies make a great deal of difference.

What I see is u are appeared to fully grasp the meaning of the graphs. Lol. Good luck with this useless product

 

[kumar402]

U18 works so well with Sonnet DAC. I like it a lot and it has replaced both Pi2AES and Digione signature to secondary setup for time being.

 

[JaMo]

@Researcher
Don't. Just don't be a troll. This is an "Is there a God" discussion. Go by your numbers and be happy with that. For us who has been around for a while and have tested and started to understand more of these secrets and the fact that measurements are good for theoretic proof but we the humans are more complex than this for HiFi music reproduction. There is more to it. The best performing gears out there doesn't measure ultra good. Because they are tuned for best sound and not for best measurements. If You will be seriously investigating these things over the years, I shouldn't surprised if You had soften up a bit about this. As @MartinWT wrote: "I say we don't measure the right things that correlate with sound quality.". I find this true where I stand today after many years of investigating these "secrets".

So please don't criticize other people with other insights than Yours. Be happy pass on the very good U18 and get an excellent spec but probably a bit dull and fatiguing DDC instead. I wish You good luck with Your journey.
/Jan

 

[kumar402]

@Researcher one of the reason I posted above pic is just to show I own 3 DDC right now and also had SU-6 with me for few days. I have Pi2AES since start of 2019 well before it got popular and Digione signature since 2018. Pi2AES is a wonderful product and has buffered I2S for my Metrum DAC.I was using it non stop for 3 years now and will continue using it but when I put U18 in my chain the first thing that I noticed was tactility in bass and wider soundstage. I mean I didn’t A-Bed but it was apparent on first listen itself. Im not sure if 400 vs 70 ps makes any difference but I had positive result in my subjective test out of 400ps jitter

 

[801evan]

@Researcher one of the reason I posted above pic is just to show I own 3 DDC right now and also had SU-6 with me for few days. I have Pi2AES since start of 2019 well before it got popular and Digione signature since 2018. Pi2AES is a wonderful product and has buffered I2S for my Metrum DAC.I was using it non stop for 3 years now and will continue using it and when I put U18 in my chain the first thing that I noticed was tactility in bass and wider soundstage. I mean I didn’t A-B but it was apparent on first listen itself. Im not sure if 400 vs 70 ps makes any difference but I had positive result in my subjective test out of 400ps jitter

Very helpful post. Yea, like the Xspdif2 was measured so well by ASR but its own of the worst ddc for me. I even powered it with hdplex + lps1.2

 

[JaMo]

A thing not mentioned here so far, I think, is the importance of the burn in process. To get fully stabilized internal oscillators You got to have a full two weeks of power on (~340hrs). To get the fully burned in/stabilized electronics, You need 6 to 8 weeks of playing music 24/7 (~1000-1350 hrs).
For many of us, this is sort of normal or standard for digital gears. An extreme example in this aspect is Audio-gd's analog amps, both pre- and poweramps. Half a year is needed (!) to get them to sing out fully. The burn in period is a kind of a "roller coaster" with good days and bad days when You can wonder if this was a good idea buying this lousy bad sounding box and one day, suddenly there is happiness. Beautiful music flowing and wide smile on Your face. You can finally thank Yourself for being patient, waiting for this WOW!-moment. A very rewarding feeling.

To wrap up. In analog gears I doubt it is possible to measure these differences between the "before" and "after" finished burnin process. For digital gears I am sure it is possible find differences in the timing. In digital gears it is in this time domain the most important stabilizing is done. But this includes FPGA/CPLD's, PSU parts, capacitors and buffers (amps), biased material from factory normalizing..

To wrap this up. Never underestimate the need for a full burn in process of serious gears. It is vital for the full function and to unleash the full potential of the gear. Good/serious gear designers often add these recommendations with the delivery but You will get far with these "thumb rules" above in this post.

This is the Gustard U18's thread so I add that these recommendation is also valid for this very nice DDC, the Gustard U18.
Thanks.
/Jan