Can a SPDIF/Toslink 1x8 out support 24/192? Please help!

[Inkey31]

Hello,

I am currently running 7 DAC's on my Desk and I am using SPDIF out of my motherboard to the amp below, however I was recently told that USB is much better then SPDIF due to SPDIF not supporting 32 bit or 24/192. I understand 32 bit inst needed for listening to music, but 24 bit is.

I did find that most AKM chips that handle SPDIF do do 24/192, yet... does it still do it if you have split the signal?

https://www.amazon.com/gp/product/B07RWQX9PM/ref=ask_ql_qh_dp_hza

 

[NTomokawa]

7 DAC's

Seven DACs? What kind of surround-sound system are you running?

 

[Inkey31]

Maybe someone could advise on a better method to hook up 7 DACs to one source?

 

[Inkey31]

Seven DACs? What kind of surround-sound system are you running?

They are all headphone AMP's and DAC's.

Currently I am using my ADI2, Schitt Gungnir MB, Schitt Modi 3, Modi 3 MB, THX 788, R2R Airist (POS), and a Toppping DX30 Pro.

 

[NTomokawa]

Connections aside, I'm curious how you're running seven DACs without having their clocks drift out of sync relative to each other.

 

[Inkey31]

Connections aside, I'm curious how you're running seven DACs without having their clocks drift out of sync relative to each other.

I have no problems at all having on all my headphone amps and DAC's on and switching between all of them streaming from Tidel and listening to flacs on Fubar.

Currently, I have SPDIF out to the AMP I linked above, then that has 8 SPDIF outs, I out into the DACs.

I am worried about quality however.

 

[NTomokawa]

I wouldn't call 24-bit needed for listening to music. 24-bit has objective advantages for mastering and post-processing since it provides more "wiggle-room" but for playback the extra bits are just noise.

That said, it makes me feel better, so I get you.

If that splitter doesn't resample anything, then whatever you're getting out of its 8 output ports should be the exact same as whatever it's receiving, i.e. whatever your source itself is outputting.

 

[Inkey31]

I wouldn't call 24-bit needed for listening to music. 24-bit has objective advantages for mastering and post-processing since it provides more "wiggle-room" but for playback the extra bits are just noise.

That said, it makes me feel better, so I get you.

If that splitter doesn't resample anything, then whatever you're getting out of its 8 output ports should be the exact same as whatever it's receiving, i.e. whatever your source itself is outputting.

Nice, thank you.

Is there a way to check and see what you are outputting? Or a way to check the signal coming out by testing the signal coming out of the cable? I am not sure if there is a tool that can do this or something of that nature.

Or software I can use on my computer to see what am I running at?

 

[NTomokawa]

What music player are you using?

If you're on Windows 10, you could go into your Sound Control Panel, select your output device, and see what's selected under Default format in the Advanced tab.

 

[Inkey31]

What music player are you using?

If you're on Windows 10, you could go into your Sound Control Panel, select your output device, and see what's selected under Default format in the Advanced tab.

It does give me the option to select 24/192, so I was hoping that the answer to question was the one you listed above.

However, it seems that USB or Coax does do a better job handling this, would you concur?

From my understanding yet it says 24/192, its hard to say thats what its really running at do to jitter? IDK if this is true or not.

 

[NTomokawa]

it seems that USB or Coax does do a better job handling this, would you concur?

I don't know. Stay tuned though; one or more of the many technical gurus of our fine forum are bound to show up and answer your questions to your satisfaction.

 

[Inkey31]

What music player are you using?

If you're on Windows 10, you could go into your Sound Control Panel, select your output device, and see what's selected under Default format in the Advanced tab.

I am using tidel and fubar 2000, too

Thanks for your help man, I really appreciate it.

 

[Doodski]

USB generally will have a higher rated output if available. The specs for your specific unit should indicate what the outputs are capable of.

 

[Casey Leedom]

I had thought that the limit was 96kHz/24bit x 2 channels. But if you look at the Wikipedia page for S/PDIF, it doesn't show any maximum Data Rate, though it does show that 20bit support is standard and 24bit is optional. One of the more interesting aspects of S/PDIF covered in the wikipedia page is:

The receiver does not control the data rate, so it must avoid bit slip by synchronizing its reception with the source clock. Many S/PDIF implementations cannot fully decouple the final signal from influence of the source or the interconnect. Specifically the process of clock recovery used to synchronize reception may produce jitter. If the DAC does not have a stable clock reference then noise will be introduced into the resulting analog signal. However, receivers can implement various strategies that limit this influence.

Generally, I've heard that USB or HDMI Transport of Audio Data works better because the Receiver can Flow Control the Sender, etc.

Of course, once you enter the obscure world of DSD, then life gets messier. There is no formal specification for DSD over USB in the USB Audio Streaming standard, so a hack was developed to allow DSD Audio Data to be encapsulated in PCM Audio Data Frames called DSD over PCM (DoP). These days there are "Native DSD over USB" implementations, but as far as I can tell from looking at the Linux kernel sound/usb/quirks.c, it's all based on USB Vendor and Device IDs rather than any interpretation of USB protocol headers.

Casey

 

[DonH56]

Nothing I know of actually sends 32 bits to a DAC, and no DAC (aside from some very low-speed instrumentation DACs) have anything like 32-bit resolution. 32 bits is often used by DAWs (digital audio workstations) but I don't think any final mix outputs that many bits (I could be wrong, but stand by my assertion that the DAC itself won't support 32-bit resolution).

The default resolution for S/PDIF is 20 bits with 24 bits optional; chances are most things today support 24 bits. Whether or not it has the bandwidth to handle 7 or 8 channels at that bit depth (or any bit depth) I am not sure; I thought it topped out at 5.1 for DVDs (16 bits, 48 kS/s) and two chanels at 96 kS/s but have not kept up. I don't think the standard itself sets a limit on sampling rate but leaves it up to the manufacturers of the chip sets (again, not my field, so I do not know).

Older chip sets actually had better jitter performance than the current crop IIRC. It is a bit harder to buffer the data and isolate the clock in a S/PDIF environment since you have to make very sure you stay in synch or you will lose bits (bit slipping). There is no Rx synchronization method in S/PDIF AFAIK -- no way to tell the Tx to resend bits. Ditto errors, though errors are essentially nonexistent unless the cable is bad or noise extremely high; no way to resend packets if errors are detected.

USB can have power/ground isolation issues but Amir's tests show you good products that do not. USB is generally more robust and has much wider bandwidth, assuming the OS is not impacting the bit stream, and supports higher rates and resolutions.

Bottom line: I'd use USB.

FWIWFM - Don