Does the Allo DigiOne Signature or All USBridge Signature Provide Better SQ

Wanting to have Raspberry Pi Roon endpoint. Would you recommend the Allo DigiOne Signature or Allo USBridge Signature for sound quality? Thanks for your thoughts and comments

Title should have read “Does the Allo DigiOne Signature Player or Allo USBridge Signature Player Provide Better Sound Quality”.

The Allo DigiOne Signature provides very clean output–better than the Allo DigiOne which I have. Whether you can hear the difference is moot. Both provide textbook performance.

I can’t comment on the USBridge but I’d say that Allo are technically competent and back their claims with measurement.

Also, it’s be helpful if you stated what DAC you intend to use with the Allo as this may help determine whether USB or S/PDIF is best.

Martin- Sorry I am just now getting back to you. Greatly appreciate your input. Thanks for the info from ASR.

I have the following DAC’s:

  • Pro-Ject Pre Box 2s - for casual listening/headphone station
  • Cambridge DAC Magic - for casual listening
  • Exogal DAC- Serious listening
  • PS Audio Perfect Wave DAC- Serious listening

Was thinking of using either Chromecast Audio or Raspberry Pi (via wifi) for the first two DAC’s… For the Exogal i was considering the USBridge Signature. The PS Audio would continue playing through Mac Mini via USB (which would be my Roon server).

Thanks again for your input and help,

Greg

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This is an interesting question. What you’re doing with both of these is catching packets off the Ethernet (or WiFi) and forwarding the bits of the music, unchanged, whether in PCM or DSD format, on to your DAC. So I’d suspect the USB (USBridge) would be preferable, as the asynchronous USB Audio protocol should work better than the source-clocked S/PDIF you get with the DigiOne, but the difference, if any, is probably not important.

But frankly, if your DAC supports USB input, I don’t see why either of these is preferable to a simple Raspberry Pi 4, which at $80 seems like a better deal all around. I suppose if you have an old DAC or a poorly engineered one which is susceptible to analog electrical interference over its USB input, you might want something more like the USBridge device. But in that case, why not use optical S/PDIF with something like the HiFiBerry Digi+ Pro at $140, and get full electrical isolation?

Bill thanks for the input. I found the article by Audio Science Review and from what I read they feel that USB is better.

I had also considered the Raspberry Pi 4. Understand the way it is designed that it have less noise with USB. However, found this article indicating that RPi 3+ sounds better than RPI 4.

Which software would you recommend for RPI option (no hat)?

Thanks for your help.

Greg

Still trying to learn about all the options. Seems like it is never ending information and keeps changing with technological changes.

It’s not really that bad.

There’s still a lot of misinformation floating around, some of it is old wives’ tales (never true) and some of it was once true but is now obsolete. And I’m sure I don’t understand some of the subtleties, but here’s what I’m reasonably sure of.

The SQ of the digital side of the house is entirely determined by the Roon Core. It knows what’s in your music files, what your DAC is, what DSP you’ve asked for (if any) – and remember that Roon volume control is DSP – and it figures out what bits your DAC should be seeing. The entire job of the rest of the system is to get those same bits from your Core machine to your DAC unchanged. So there are only three things that matter:

  1. you use the correct cables, by which I mean that you use Ethernet cables certified for the speed of the Ethernet ports you are plugging them into, and you use USB 3 cables on USB 3 ports, USB 2 cables on USB 2 ports, etc.; and

  2. the chain from core to DAC is fast enough to keep up with the required bandwidth – the bits have to come at a speed that keeps the DAC busy; and

  3. the software on your streamer, if you use one, doesn’t muck with the bits.

You don’t have to worry about audiophile cables or linear power supplies in this part of the chain, because those are analog considerations and this is all digital. So a simple Raspberry Pi with the standard Pi power supply running RoPieee will be fast enough. The issue with the Pi 3 was that the Ethernet port and the USB ports shared a hardware controller, which caused problems. Not sure of the details, but it’s almost certainly a speed issue – the software drivers running on the Pi didn’t respond to hardware interrupts quickly enough, and packets were being dropped. In the Pi 4, this issue has been fixed (which to my mind calls into question why the Allo USBridge Signature even exists anymore).

The video you cite seems to me to be nonsense. I have to confess to never having learned anything I trusted to be true by watching one of Hans’ videos. He never uses that measurement equipment in the background, and he does these drive-by inanimadversions like calling the Pi’s USB “polluted” with no proof of that. (Folks who have actually put scopes on that USB port apparently haven’t found that “pollution”.) Since the only purpose of the streamer is to take the bits Roon thinks are the right ones, and send them to the DAC, and since a Pi running RoPieee is a very stripped-down very quiet computer with no moving parts dedicated to talking to the Core over the network and conveying the bits properly, there’s no non-magical way the sound of a Pi 4 could be worse than that of a Pi 3. In fact, with the separate USB controller, it should be better.

He is using hats on his Pi, though. I think hats introduce an extra layer of complexity and format conversion that is largely unnecessary, so I avoid them. Maybe his hats are causing the differences he claims to hear, or maybe it’s imaginary.

Again, the only purpose of the streamer is to convey the bits Roon thought were right, to the DAC. The DAC creates the analog sound of the music.

If you have old DACs which were improperly engineered, maybe because the shop that built them was an analog house and didn’t understand digital interfaces well enough, you might have electrical interference issues. But you wouldn’t want a DAC built by people who didn’t understand digital engineering, would you? Digital input to audio gear has been around for quite a while; here’s a nice explanation of the S/PDIF protocol from 2004, for instance. 15 years ago. Don’t buy badly engineered DACs, would be my advice.

And there are special cases. For instance, if your DAC is powered by the USB cable, as with the AudioQuest Dragonfly series, you have actual electrical coupling issues to consider. Buit any halfway decent DAC will be filtering that power input.

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Bill thanks for the input it was very helpful. So if I understand you correctly you would recommend the RPi 4 with Ropieee and a standard power supply. This should be all I need. Is Ropieee hard to install and do I need the 7" Raspberry monitor to be able to install Ropieee? When looking at a beginners guide for installing Ropieee they had recommended using the monitor.

Thanks again for your detailed message and help.

Greg

To my mind, using the monitor just adds complexity to the system, so I wouldn’t use it.

Anyone who can cable together a component audio system can snap together a Raspberry Pi. You download RoPieee to an SD card and slide it into the SD card of the Pi, and RoPieee takes it from there, pretty much. Instructions are on this forum. I’d recommend the Cana kit starter kit with a 1GB Raspberry Pi 4. I use a Pi 3B+ with WiFi, which also works perfectly well because I’m not using the Ethernet port for anything and my WiFi is fast enough.

I use a USBBridge Signature,(with roon rock on a nuc) with a Shanti psu
Now I can you recommend it!
More can I not say as listen to it and compare than you hear the difference :violin:
I’m happy with my usb bridge, play with Ropieee :notes:
Next week I try the Digione signature to my hegel.
Ben :wink:

I’m sure it sounds just fine. But I’m also pretty sure it sounds no better than a regular Pi 4 with the regular Pi power supply. Digital is just that way – there’s no way around it.

What kind of DAC are you running it into?

Hi :grinning: I go not say what you must do or hear… and you hear no difference… , hold what make you happy :+1:
I’m hear a different in my ears :violin::notes:
I do not like the standard power supply …
Than I do not more listening to the music to my hegel.
Ben :wink:

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I strongly disagree with this. A USBridge Signature with a Shanti PSU sounds (to me, at least) significantly better than a Pi 4 with regular Pi power supply.

Not even close. Night and day difference…

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OK. So how do you suppose that works? The only way the sound is changed is if the bits sent by the Roon core are changed by the USBridge into different bits before it sends them to the DAC. Is that what you’re suggesting happens here?

If so, is that really what you want? How does the USBridge know what what changes to make? Wouldn’t the Roon Core be in the best position to figure out the optimal bits?

I’d appreciate it if you’d suggest a plausible mechanism for this if you’re going to bring it up. Ideas are good!

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Bill thanks for the information. I will try RPi4. Want to do research on setting up Ripieee. I might be getting back to you if I have questions on the setup if you do not mind. Thanks again for your kind help,

Greg

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List of DAC’s:

  • Cambridge DAC Magic
  • Pro-Ject Pre Box S2
  • Exogal
  • PS Audio Perfect Wave

Thank for your help.

Greg

Bill thanks for your input.

Greg

The comparison is beyond me from a technical standpoint. Wish I had the ability to do a side to side comparison.

Thanks for everyones input as I am try to learn.

Greg

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I highly reccommend the allo usbridge sig. as endpoit . i didnt test the digione yet

https://www.hifiberry.com/blog/the-raspberry-pi-4/ nothing has changed with Pi 4 still noisy.
Tried one returned and my RME ADI-2 is pretty good at cleaning up USB signals.
What am I comparing it to try a Clone PC running Windows 10…search for RME ADI-2 thread for details.
Allo know their stuff has a good price point and the USBridge Sig is much easier to setup than a PC.