• Welcome to ASR. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Pass-through / convert from optical **to** USB

@john61ct Idea: Get a Toslink to USB adapter, plug it into something like a Raspberry Pi, then somehow send that output through the Pi's USB ports. The info for how exactly to do this is all over the place, so here's a potential quick implementation from Grok: https://x.com/i/grok/share/CD92DqzOR6yNIlt11E6mtOlWm

The best part? All you need is "something" that runs Linux so it could be an old PC, some super cheap Raspberry Pi competitor, etc.
 
Last edited:
bachatero said:
something like a Raspberry Pi, then somehow send that output through the Pi's USB ports
Click to expand...
LOL bit of a kludge there! but sure, thanks

If it turns out there are no reasonably priced turnkey boxen out there, such a project might be a cheaper / smaller path forward, not just challenging but maybe fun!
 
Not a very specific one. In my ignorance of the details of USB protocols, I had assumed any-to-any conversion was routinely possible, and in general, just wanted to be able to take a S/PDIF signal and feed it to devices that only accept USB.

A dongle from Sennheiser "BTD 700" (Auracast, aptX Adaptive) was my nominal spark, but of course many small DACs and other device types also match that criteria
 
Last edited:
john61ct said:
Not a very specific one. In my ignorance of the details of USB protocols, I had assumed any-to-any conversion was routinely possible, and in general, just wanted to be able to take a S/PDIF signal and feed it to devices that only accept USB.

An dongle from Sennheiser "BTD 700" (Auracast, aptX Adaptive) was my nominal spark, but of course many small DACs and other device types also match that criteria
Click to expand...
Okay, this is actually a use case that makes sense, but your path of least resistance is going to be a different device. It looks like Auracast transmitters that take SPDIF in do exist: https://www.amazon.com/HomeSpot-Bluetooth-Transmitter-Compatible-Headphones/dp/B0DJ33677Q
 
  • Like
Reactions: MCH
Yes and thanks, but the more general "gadgets as USB Host" issue / question is actually more interesting to me now.

Sweetwater hasn't got back yet, I hope to delve further into the Wiim Ultra capabilities, and perhaps over time members might surface additional candidates.
 
Creative claims their Sound Blaster X5 outputs USB in Host mode.

The better reviewed SoundblasterX G6 , likely not
 
Meh, too many uncertainties there I think, but I s'pose at least it's not as pricey as that Mutec unit.

If it turned out SoundblasterX G6 did have USB Host mode that would be better value at half the price, great gaming flexibility and decent SQ for audio too.

Otherwise it seems Creative just dropped the ball over the decades...
 
Incoming SPDIF is clock master. Outgoing USB can be slave (if the USB device is isochronous adaptive - inexpensive headset), or master too (if the USB device is isochronous asynchronous - basically all DACs these days). Two clock masters in one chain must be aligned via asynchronous resampling - not trivial.

Then the question of compatibility of devices with the UAC1/UAC2 standards (which are quite loose by themselves). Only a subset of devices support the standard flawlessly, many require some quirks. It takes a linux kernel => computer (which can be embedded in a device, of course) to support most of the devices. I have yet to hear of a non-linux embedded solution which would be close to the level of USB-audio support.

As of that Creative card with USB-A host port - either it supports only limited selection of devices (with UAC1 adaptive which could be hard-coded in some chip), or it has embedded linux (I very much doubt it), or the port is simply output of an integrated USB hub and the attached devices will appear as devices in the connected host computer (IMO quite likely). I could not find any detailed specs in this regard, neither on the vendor website nor in the user manual.
 
There are these modules, which I have no clue how they work + I believe they only do uac1

emPower-USB-Host board

Evaluate SEGGER Software (embOS, emUSB-Host) on SEGGER emPower-USB-Host
www.segger.com www.segger.com
 
MCH said:
There are these modules, which I have no clue how they work + I believe they only do uac1

emPower-USB-Host board

Evaluate SEGGER Software (embOS, emUSB-Host) on SEGGER emPower-USB-Host
www.segger.com www.segger.com
Click to expand...
UAC1/2 support of that embOS is actually quite comprehensive, including explicit async feedback https://www.segger.com/doc/UM09001_emUSBD.html#Audio . Of course no device quirks. Nice, thanks for the link.

Of course async resampling would be required (but it can be hardware-based and running permanently).
 
phofman said:
Of course async resampling would be required (but it can be hardware-based and running permanently).
Click to expand...
You will definately need a hardware solution for this. A 180 MHz M4F will not be fast enough to run high-quality ASRC. You'll have to significantly lower your standards to run it on the device, and even then, only at maybe 48 kHz or so. Ti SRC4392 is your best friend :)
 
Last edited:
staticV3 said:
Though sub integration via mixed-format Analog out+Async USB out may not work well due to clock drift.
That's a general concern, not specific to the WiiM.
Click to expand...
As I understand it PipeWire added the capability to handle this a while back, and from a conference presentation it seems use cases like TVs, streamers and soundbars were a target. They compared the cpu usage to a couple of alternative methods, so it's not the only way. I think the advantage was that you could mark inputs and outputs with a clock domain so ASRC was applied only where there was a difference in clock domain, rather than being all or nothing. The point is there are ways to solve this problem. Whether Wiim (or others) are using them is another matter.
 
I don't mind people posting DIY / techspeak above my understanding if that helps others in the community, but just to clarify MY OP context

I am looking for finished, "deployment by noobs ready" audio-specific gadgets

TOSlink input --> USB Host output

solutions at high SQ, the expectation with digital conversion is fidelity and transparency, so the clocking issue must be a solved one, not a DIY project more complex than using an actual OTS Linux host.

Wiim Ultra seems certain to work just fine.

I agree Creative is sus.

Waiting for confirmation on the Mutec 1.2+

So far that's it...
 
With a Raspberry Pi with a HAT you can have USB, optical, HDMI, coaxial, etc. May be an option for you and very cheap.
 
Nicoff said:
With a Raspberry Pi with a HAT you can have USB, optical, HDMI, coaxial, etc. May be an option for you and very cheap.
Click to expand...
Yes bit of a DIY project, but sure, thanks

If it turns out there are no reasonably priced turnkey boxen out there, such a project might be a cheaper / smaller path forward, not just challenging but maybe fun!
 
john61ct said:
Yes bit of a DIY project, but sure, thanks

If it turns out there are no reasonably priced turnkey boxen out there, such a project might be a cheaper / smaller path forward, not just challenging but maybe fun!
Click to expand...
Also, have you looked into a WiiM product? Those are fairly inexpensive and not DIY project.
 
Yes, see #10

Note that only the Ultra has USB output, it's a full Host mode port.

Just the PEQ / room correction / HP-LP sub crossover bass management makes it good value!

Nicoff said:
Also, have you looked into a WiiM product? Those are fairly inexpensive and not DIY project.
Click to expand...
 
You must log in or register to reply here.

Similar threads

F
Looking for DAC with USB in, balanced line-out, Coax out and HP amp
2
Replies
20
Views
1K
FlyingTeuton
F
G
Searching for a digital preamp with multiple digital inputs and outputs.
Replies
7
Views
902
somebodyelse
S
ICIETDIYEUR
New SMSL C200PRO
Replies
13
Views
4K
KillerCars
K
T
Question about wiim streamers doing Toslink to coaxial transport
Replies
14
Views
1K
kemmler3D
kemmler3D
I
How to apply Dirac Live Processor to my Play Station 5 Pro sound?
Replies
5
Views
780
Keith_W
Keith_W
Back
Top Bottom