I don’t agree with you there, bias is very much in effect when you start listening to your new equipment, but falls off over time. If you swap between equipment with short delays, you need to do it as a blind test.
For me, its much more reliable to listen to the new stuff for a few days, and then maybe switch back.
I can take an example: I added some internal metallic screens between the two boards in my NC500 power amplifiers. I was sure it was going to make an improvement, and at first I though it did. But a few days later I felt it hemmed in the sound somewhat, so I removed them and realized that the tweak was not any good at all. That’s an example of how to overcoming bias, and the reason you hear a lot of experienced audio people say that you should listen for longer period of time before deciding if its good or not.
You can perhaps do a blind test yourself, borrow a mR without the upgrade, swap them around until you don’t know which one has the upgrade and then try to decide by listening in any way you want which sounds better.
Hey, I’m an old man too so be nice… Joking. I have an utraRendu 1.2 I believe (how do you tell?) using NAA and powered by SBooster 9v PS and also a few Rpi 4’s laying around.
I booted up a Pi4 with the HQPlayer NAA image. Used the same ethernet cable (Cat 6 unshielded generic brand) and USB cable (AQ Carbon) to my Denafrips Pontus II dac and also powered the Pi4 with a battery pack. If there is a difference, it is very small and I would have to really, really, pay close attention to notice anything different (if there are any differences all).
Conclusions… possibly my network is relatively quiet via ethernet, my Pontus dac has a good USB implementation, I don’t have ground loop issues, and maybe my hearing is not up to it.
YMMV
PS, I’m keeping the ultraRendu, got it used for a good price, I like it.
Sender side. But DAC side has two clocks; USB/MCU clock and audio clock separately. Unless it is some really poor implementation.
Usually USB clock is some regular inexpensive part.
And the two audio clocks (22.5792/24.576 MHz or 45.1584/49.152 MHz) are high quality since these are the ones that matter.
ADI-2 doesn’t have galvanic isolation, so you need to pay some attention on your signal paths. Buf of course this has nothing to do with USB clocks or such. It is just about analog paths through the USB connection.
Well, I haven’t experimented with USB clocks in the receiver (DAC) so I am not 100% sure about this, but the USB sender clock definitely matters. And I know you like the May DAC so I checked it out and their improved USB receiver card mentions an improved USB clock and it certainly looks like a Crystek clock (its above the XMOS but hard to tell for sure).
But instead of theory-crafting, take a leap of faith and listen instead on for example a quality streamer, we are dealing with HiFi after all
That board in picture certainly doesn’t have a fancy Crystek clock, because it is so small. I have tubes of Crystek CCHD-957’s for both audio clock frequencies. And they are much larger 9x14 mm package.
And the board in picture is the one I have in my DACs, not the new fancy one. Although the one in the picture performs perfectly fine (measured).
In any case, I’m interested to see hard measurement data from the DAC analog outputs showing these differences.
Any updates here please @Magnus Or in general in regards to USB reclockers in NAA context? Do you have a favorite right now from your personal experience? In case you like e.g. an I2S reclocker,please mention too. Myself not limited to USB only. (Although measurements and theory much more important to me now and starting to learn on that, myself will not do that „=„ between measurement and SQ, as you pointed out too.) + Any share of experience with reclockers by you or someone reading it highly appreciated!
I don’t own a reclocker myself, but I have heard them in action. Also, somewhat similar, updating the clock in the streamer I use to a Crystek made a big difference (its the 24M clock for the USB protocol).
In fact, a streamer is also a reclocker so if you have a good enough streamer you won’t need a reclocker. A friend of mine owns a streamer from Pink Fauna with an very good OCXO clock, but it quickly gets very expensive when you look at those kind of streamers.
I did the opposite, starting with an Allo USBridge, and yet today I use an RPI4 almost permanently. I have a Musician dac which has a galavanic isolation of the USB (the circuit tests for the presence of the usb + 5v and then switches to its own internal 5V).
I wanted to buy a RPI4 in december for fun and testing. It turns out that I can’t get the RPI4 to recognize the dac, while everything works with the CM3 compute module of the Allo.
But with a simple usb hub, it works (!!).
Anyway, I had an Ohlenbach reclocker (basic) in my cartons, which can now play the quality hub.
This little box is now sold for a small price (80$) and even includes a quality power supply (MeanWell 7.5v GST25).
As I have a Shanti with 2 outputs, I supply the Rpi4 + reclocker with 5v. All under my special PicorePlayer/NAA. Well, I prefer it to the Allo which seems more “dry” and less " joyful ".
Thank you very much for sharing ! It has a Jitter cleaner as well. This is cool! For asynchronous USB, I assume Jussi and dabass will tell us, that the audioclock is done by the DAC…hihi…dabass will roll over, telling that in regards to jitter only the DA step is relevant, if you pass bitcorrect to DAC…i assume but you like the sound with that little guy more instead w/o it, if i get it right?
(did order the little Oehlbach from their promotion offer, that you thankfully posted. Thank you again for sharing! @Stef_Dahl )
+++Well for HQP PCM Output still love Hifiberry Digi2Pro via I2S Pi - Tos (so no USB at all and 192 only upsampling sounds great to my old ears), disadvantage not really doing SDM with that specific hat that way. Believe DoP64 only possible. So paying around to optimize USB. Right now using a PI400 for that.
Only in regards to Jitter (no reclocking):
Well another interesting review in this context and for this thread imo. Myself still learning on this please.
It’s also that my dac was not recognised by the RPI4 and that it only worked with a hub… so as a hub, I prefer this box.
I connected it to the RPI on the usb2 port and added the “right” command line to disable the USB3 ports.
A Zen stream certainly works as well but it is limited to DSD256 and seems less ‘open’.
Yes, that’s the case. If your USB connection is computer → NAA, then there’s nothing to clean up. It is no different than connecting a USB HDD or similar.
For DAC connection, any USB reclocking doesn’t matter, because USB clock is not related or involved in audio clocking in any shape or form. It just facilitates moving bits between two memory buffers.
USB isolators may help depending on the DAC (whether it has built-in isolation or not).
When i moved in my new house two years ago, i upgraded my audio system. Part of my upgradejourney was to test if a Innuos PhoenixUSB could make a difference.
So i orderded one to test en set it up between a mac mini with Roon and HQplayer and a Hegel H590. Later between the mac and a Holo Audio Spring3.
I found that The PhoenixUSB was not a minor accessory but a necessity to use.
Difference is night and day. It did more for my system then the AudioQuest Niagara 1200.
I recon my findings are somewhat contradictionary to what Jussi said above.
My recommendation is that if you consider a PhoenixUSB, you test one.
A good clock on the USB source does indeed help, even though I am not sure why. And remember that we are clocking the USB protocol, 24Mhz, and not any audio data.
Maybe a good USB protocol clock helps reduce the DACs work in decoding the signal and hence results in less electronic noise internally for the DAC.
but you like the sound with that little guy more instead w/o it, if i get it right?