Gustard R26

@Kairosman - from my reading the conventional wisdom is most DACs when fed sources like I2S, s/pdif and AES that contain a synchronous word clock will use that embedded clock signal untouched so theoretically at least a master clock connected to the DAC wouldn’t be used to reclock the stream so would be of no benefit. And that conversely with asynchronous sources like USB and ethernet they are of necessity reclocked by the recipient DAC/ streamer and so if the DAC/streamer is being slaved to a master clock you’ll get the benefit of its greater temporal precision. Indeed from memory Gustard’’s R26 product blurb that appears on vendors’ sites is consistent with this referring to the USB and Ethernet inputs being reclocked.

So far so logical. But then it gets rather less clear cut with:

a) a clarification Gustard provided over email to a Headfi member (copied verbatim below, ambiguous punctuation and all) that suggests - depending on how you read the punctuation - that all the R26’s inputs benefit from an external clock with NOS & DSD DIRECT OFF (ie over sampling ON) but with NOS/DSDD ON only the asynchronous inputs, USB and ethernet, benefit; and

b) at odds with a) my observation from careful testing that there is a satisfying audible benefit of toggling an EXT Clock ON for I2S and s/pdif regardless of the NOS/DSDD setting. Fairly sure a number of other Gustard *26 owners who use I2S and NOS/DSDD also find a good benefit with an external clock. As to the mechanism of action/benefit from the external clock if these synchronous inputs are not buffered and reclocked (which would seem unlikely), your guess is as good as mine!

It has become apparent there’s substantial language barrier/translation error risk factor with any comms with Gustard, so a pinch of salt with all their comms and publications especially on nuanced technical points is wise. Eg. They accepted the manual had a translation error re DSD processing.

Credit to HF member MMWMM:

This is an answer from Gustard regarding the use of a 10Mhz external clock with the R26 and when its clock signal is used to reference the internal K2 synthesizer and when is not used.

“When playing PCM

1. PCM NOS: OFF
The improvement provided by the external clock applies to all R26 inputs.

2. PCM NOS: On
The improvement provided by external clock applies to USB and LAN inputs, IIS AES coaxial optical Bluetooth does not apply.

When playing DSD

1.DSD DIRECT: OFF
The improvement provided by the external clock applies to all R26 inputs.

2.DSD DIRECT: ON
The improvements provided by the external clock apply to USB and LAN inputs, IIS AES coaxial optical Bluetooth does not apply.”

@arafiq I use the R26 streamer with Roon and HQplayer, faultless operation and sounds great. I use HQP upscaled PCM768 & DSD512.

I prefer the sound of the R26 internal streamer to my Ifi Zen Mini (+ IFI Power X) > Gothic Audio pure silver Outsider USB cable > Gustard U18 DDC > BJC FE I2S > R26. I actually found using a USB direct connection from my server to the U18 (albeit with the Holo Titanis USB regenerator plugged into the server) to be better than the Zen > U18, and closer to but still some way behind the R26 internal streamer. With an external clock in play the gap widens.

That said I know of a few folk with better streamers (like the Ifi Neo Stream) or servers (such as with $2k JCAT USB & ethernet upgrades) who prefer I2S and/or USB connection to the internal streamer. 

@kereru thanks for the info! Out of curiosity what other DACs have you got to compare the R26 to?

@kairosman Nothing more exotic right now alas. My only point of comparison was a head-to-head with a similarly priced and since returned SMSL AK4499 VMV D2 DAC last year, which the R26 beat handily. Oh and a Topping E50 they both destroyed. R26 & D2 were using the Zen/U18, Roon/HQP and an Ock-1.

All I know is that my R26’s sound has improved out of sight since then with network chain improvements, better external clocking and signal grounding (I can’t recomment Quartz Acoustics Premium grounding boxes highly enough). If the ’stock’ I2S input R26 YT reviewers compared favourably with R2Rs up to maybe the level of the Pontus/Venus and the Spring 3, then I reckon (he says, perhaps a little optimistically) in my more optimized setup it’d now surely soar well past them, if perhaps not quite as far as your Baltic 4...

@soix

and in the end it’s what’s on the inside that counts unless you’re an insecure audiophile who needs the bling to show it off to friends. I’m not one of those.

I don’t think it’s fair to assume that audiophiles who care about how the equipment looks are necessarily driven by the need to ’show it off to friends.’ Many audiophiles, myself included, care about the way our equipment looks. If I’m listening to my music I also tend to look at the speakers, amps, racks, etc. At least for me it adds to my enjoyment if the view is equally pleasing to my eyes. I’ve put in a lot of effort to make my listening room aesthetically pleasing (to my eyes). It is important to me that the equipment fits in with the overall vibe of the room. But I can assure you, it has nothing to do with showing off to anyone else.