New Audio-GD DI-20?

[Confused]

An interesting product.  In my case I use a Mutec MC3+USB fed from a Mutec REF10.  The REF10 is a keeper, but I would be interested in anything that might out perform the Mutec MC3+USB, which is a fine product but is arguably held back a touch with it's built in switch mode power supply.

 

So if anyone ever puts one of these head to head with the MC3+USB, I would be fascinated to know the outcome.

[Confused]

I run a Mutec MC3+USB.  With the Mutec, if you feed it DSD, the Mutec itself will convert the DSD feed to PCM, reclock, then output via S/PDIF.  This I understand, and Mutec claim this is how things must work, as you cannot "re-clock" DSD.

 

This begs a question.  If I am interpreting things correctly, the Audio GD DI-20 can accept DSD via USB, and output DSD via S/PDIF / AES/EBU.  The Audio GD DI-20 also has a 10MHz input, for something like a Mutec REF10 or similar.

 

Therefore, if you were feeding the Audio GD DI-20 DSD via USB, and getting the same DSD rate via S/PDIF output, I presume this is kind of a "pass through" mode, and the REF10 (or internal clocking) would effectively be doing nothing?

 

Is this right?  Does anyone have any insight into this aspect?

[Confused]

One other question.  My only proper reference for "digital to digital converters" is my own Mutec MC3+USB.  I have searched through the 'net for some kind of comparison between the MC3+USB and the Audio GD DI-20, and basically found nothing.

 

Has anyone seen anything?

[Confused]

21 hours ago, Summit said:

 

Max DSD 128 dop is possible from the S/PDIF output.

 

Some folks on Head-fi are using the Mutec Ref 10 together with DI-20HE.

 

https://www.head-fi.org/threads/audio-gd-di-20.918123/page-68

Thanks for the link.  Plus, thinking about all this, the fact that the Audio GP can output DSD as DoP, whereas the Mutec MC3+USB cannot, I believe this answers my question in post #18.

[Confused]

9 minutes ago, Summit said:

 

Sorry my friend I do not think you are right in post no.18, there is no "pass through" mode in a DDC, and REF10 does what it does, ie works as a reference clock, no matter what output or format you use. The (reference) clock signal from REF10 is independent of whether the decoding is for PCM, DSD or DSD dop.

Actually, that is what I meant in post #21, although I could have been clearer in my post.. 

 

So to clarify, GD DI-20 can output DSD as DoP, and this can be "clocked".  The Mutec converts DSD (DoP or native) to PCM, and cannot output DSD in any form.

 

In post #18, I had not thought this through and was thinking of native DSD with respect to the GD DI-20, which in this case is irrelevant as it is DoP.

 

So some earlier miss thinking in post #18, but I think we are now actually agreed.  We are certainly agreed that I was not right in post #18!

[Confused]

@Summit - Good luck with your Audio-GD DI-20HE.  I shall be very interested to read your comparison.  I was very interested in the Gustard U16 because it (in theory) offered DSD output and 10Mhz clock input, which is what I am after.  However, after a little research I found that there are firmware issues with the U16, and basically it is not fully compatible with the sMS-200Ultra, which is want I want to use it with.  That said, I did read many subjective listening reports for the U16, and on this basis alone it seemed to be exactly what I am looking for, hence I will be very interested in how you think the DI-20HE compares.

 

I can offer you one early observation, the DI-20HE is a little larger than the U16, I am not sure if you had noticed this? 

 

Being serious for the moment, it is huge!  It makes the Gustard look like a toy.

[Confused]

@GoldenOne - Excellent review and measurements, great information and waffle free text.  I have to say that I have seen some rather disappointing measurements for some other Audio GD products, so I had somewhat dismissed the DI-20-HE.  So it is great to see some measurements for the product itself that show that is actually performs very nicely.

 

As someone who currently uses a Mutec MC3+USB, I was interested to compare the Audio GD measurements with those performed by Hifi News for the MC3+USB.  To be honest, I am struggling a little correlating the two.  See link:

 

https://www.mutec-net.com/downloads/manuals/MUTEC_MC-3plusUSB_-_HFN.pdf

 

Is it possible to correlate the HFN Mutec measurements to yours for the Audio GD DI-20-HE?

 

[Confused]

On 7/22/2021 at 10:33 PM, GoldenOne said:

I've posted some measurements of the Jitter and noise from the DI-20HE.
This thing is seriously impressive and is the best DDC I've seen thus far.

https://goldensound.audio/2021/07/22/audio-gd-di20he-measurements/

I was looking at this yesterday, and later reading a review of the Auralic Altair G2.1 in Hifi News and Record Review.

 

For the Auralic, HFN's "lab report" measurements quote jitter at 14psec at 48kHz and 14psec at 96 kHz.

 

Looking at the Goldensound measurements of the Audio GD, at 48kHz there is the level / frequency graph, which shows a reading of about 3p level (s) downwards from 20Hz, and below the graph figures (RMS) of 78.74ps and (peak) 229.2ps.

 

I am almost certainly demonstrating my own lack of knowledge here, but whilst I can easily compare one HFN measurement to another, and one Goldensound measurement to another, I cannot fathom how to compare a Goldensound measurement to a HFN measurement.

 

I presume the measurements from something like the Auralic and the Audio GD to be broadly similar, but how should the Auralic's 14psec number be compared to the Audio GD's 3p level (s), 78.74ps / 229.2ps numbers? My simple brain tells me that 3p level s is a lot lower than 14 psec, but 229.2 ps is much higher, so I am at a bit of loss as to how compare these different measurements.

 

Can anyone clarify this? I am slightly puzzled!

[Confused]

27 minutes ago, GoldenOne said:

Could you link this post? The HFN lab report I found doesn't seem to have the information you mentioned

Ha! No I cannot. The HFN article I read was in an actual magazine made of old school paper. 

 

Here is a snip of the lab report:

 

 

 

And the relevant part of the lab report words:

 

 

 

[Confused]

On 8/27/2021 at 12:05 PM, GoldenOne said:

Ahh ok, this cannot be directly equated/compared to my measurements. The ones in the article are 'inferred jitter', measures using a J-Test through a DAC.

My test is measurement of the jitter directly from the digital source. (With FFT spectrum of jitter)
I may start including J-Tests in future as well (particularly cause I can't measure I2S directly so it'd be useful to have some info on that in case it differs from coax performance significantly), but the problem is that even with the same digital source, the dac used will affect the measurement as different DACs have different approaches to PLLs, resampling etc.

Actually the most ideal DAC for the task would be a NOS, no-PLL R2R dac, such that there is no further digital processing or reclocking. The Holo May actually suits this very well given as you can disable the PLL so I'll look into that. BUT, it still can't be directly compared to the HFN measurements as they're using a different DAC.

 

Many thanks for the response, which is clear.

 

So ignoring the HFN numbers and just looking at you own measurements, these is one other thing that puzzles me a little.

 

Taking as an example your 48kHz jitter measurements for the Audio GD D120HE, the graphical representation indicates Level (s) from about 2ps / 3ps down to below 1e-13 ps at very high frequencies. What I am struggling to fathom is how this relates to the RMS level s and Peak level s readings, which are 78.74 ps and 229.2 ps respectively. In other words, 78.74ps is way higher than anything indicated graphically. I am sure that I am missing something fundamental here?

[Confused]

On 8/30/2021 at 12:33 PM, Confused said:

Many thanks for the response, which is clear.

 

So ignoring the HFN numbers and just looking at you own measurements, these is one other thing that puzzles me a little.

 

Taking as an example your 48kHz jitter measurements for the Audio GD D120HE, the graphical representation indicates Level (s) from about 2ps / 3ps down to below 1e-13 ps at very high frequencies. What I am struggling to fathom is how this relates to the RMS level s and Peak level s readings, which are 78.74 ps and 229.2 ps respectively. In other words, 78.74ps is way higher than anything indicated graphically. I am sure that I am missing something fundamental here?

I am not sure if @GoldenOne missed this one?

 

Meanwhile, can anyone answer the above question? I remain puzzled.