Add SPDIF to Topping DM7 8-channel DAC

[Dave Bullet]

If it's useful for anyone else.

I am using one of these successfully:

https://www.aliexpress.com/item/1005002592797661.html?spm=a2g0o.productlist.main.7.7d3717eeg7EyAi&algo_pvid=871e1add-b888-4f3b-af44-a00384fc21a7&algo_exp_id=871e1add-b888-4f3b-af44-a00384fc21a7-3&pdp_npi=3%40dis%21NZD%2123.54%2118.84%21%21%21%21%21%402102111816822861987407362d0716%2112000021302921644%21sea%21NZ%21122820545&curPageLogUid=JQq9Mlf2p6uc

Here's an image

It's a Cirrus Logic based cheapie USB 5.1 soundcard.

Now the ADC/DAC in it is poor quality (and has an aggressive high pass rolloff for low frequencies unless you replace the in-line caps)

However the SPDIF input seems to be straight through. It sounded identical to me, compared to a FLAC of the same CD ripped.

the chain is:
Digital transport (e.g. TV or CD player with optical out) -> USB 5.1 SPDIF (above) -> USB -> PC (running CamillaDSP with USB capture and DM7 output) -> DM7 -> amp/speakers

 

[soerenssen]

It does exist, it is called RME Digiface USB

Digiface USB - RME Audio Interfaces | Format Converters | Preamps | Network Audio & MADI Solutions

RME Audio Professional Live, Studio, Recording and Broadcast Solutions. Unrivalled Quality, Performance & Stability MADI Interfaces, Converters & Preamps.

www.rme-audio.de

It can do USB --> 4x SPDIF out and 4x SPDIF in --> USB
But you will definitely need a PC to make it work, it is not standalone

In terms of quality I would highly recommend using a PC as a source and as DSP too since then your options will become limitless - literally

I'm streaming Tidal from my WiiM Pro currently. It has SPDIF coax and Toslink optical outputs, both measure well (up to 24/192), but no USB connectivity. I will add a mini PC for 2.2 Dirac/DLBC processing, connected to a multichannel DAC like the DM7 (or the 4-channel Flex, being the only alternative around 600-800EUR with a remote controller).
Unfortunately Tidal Desktop doesn't have a Connect feature so I cannot control music playback remotely from the Tidal mobile app.

- Is it possible to connect the WiiM's coax output to the PC via USB to route it to the DM7 after Dirac processing? For this 1:1 connection which adapter would you recommend? Is there a potential quality loss with this extra conversion?
- What improvement would you expect, switching from the WiiM to PC as a source? (Tidal+Jriver might work via the WDM driver)

 

[ppataki]

- Is it possible to connect the WiiM's coax output to the PC via USB to route it to the DM7 after Dirac processing? For this 1:1 connection which adapter would you recommend? Is there a potential quality loss with this extra conversion?

We have already discussed the same topic in this thread:

HTPC's (or PC's) cannot decode Atmos surround sound

People are telling me I am wrong what I wrote in this first post, so I added this paragraph, did some text strike outs, and changed the title to say Atmos. I guess I was confused with Atmos vs regular surround. Sorry. The replies below are good though. HTPC's (or PC's) cannot decode surround...

audiosciencereview.com

You need a device with a coax in, with ASIO driver, etc...
I personally would not do it

- What improvement would you expect, switching from the WiiM to PC as a source? (Tidal+Jriver might work via the WDM driver)

With a PC you will have unlimited DSP - on top of Dirac you can have whatever VST plugins you want using Jriver

 

[soerenssen]

We have already discussed the same topic in this thread:

HTPC's (or PC's) cannot decode Atmos surround sound

People are telling me I am wrong what I wrote in this first post, so I added this paragraph, did some text strike outs, and changed the title to say Atmos. I guess I was confused with Atmos vs regular surround. Sorry. The replies below are good though. HTPC's (or PC's) cannot decode surround...

audiosciencereview.com

You need a device with a coax in, with ASIO driver, etc...
I personally would not do it

Yes I know. I meant connecting the Wiim's coax or optical out to the PC's USB using one of these converters, not to the DM7 directly.

 

[ppataki]

using one of these converters

Which converters?

 

[soerenssen]

Which converters?

The multiple SPDIF to USB converter from RME libked earlier in this thread or alternatively a cheap 1:1 converter since I have a single SPDIF source. I would connect the USB to the PC, not to the DM7, hoping that it can be routed to the analog outputs. Maybe I misunderstood and it's a dead end.

 

[ppataki]

The multiple SPDIF to USB converter from RME libked earlier in this thread or alternatively a cheap 1:1 converter since I have a single SPDIF source. I would connect the USB to the PC, not to the DM7, hoping that it can be routed to the analog outputs. Maybe I misunderstood and it's a dead end.

The RME that I linked (and which I use) is a multichannel USB to SPDIF converter (not SPDIF to USB)

You can connect the Wiim's SPDIF output to a PC using a device that has an SPDIF input (such as the MOTU we mentioned already)
This would be the 'SPDIF to USB converter'

As mentioned, this is a bit tricky
Instead, just use the DM7 with your PC as the source

 

[phoenixdogfan]

Why is using a computer not allowed? How else are you going to use the DM7 unless it is connected to some sort of USB host (whether Mac, PC or Linux)? Are you looking for 3 or 4 stereo (not clock synced) SPDIF inputs? Or 3 or 4 clock sync'd inputs? Can you describe your source(s) in a bit more detail? Are they variable sample rate?

If you only need 3 or 4 stereo SPDIF inputs you could use this -> https://hifimediy.com/product/s2-digi/ with an automated SPDIF switch like this -> https://www.tindie.com/products/beni_skate/automatic-spdif-opticalrca-audio-switch/. In any case you will need a USB to host to route the signal captured by the SPDIF to USB card to the DM7. See my signature for a tutorial on how to do this with a RPi4 and CamillaDSP, there are also other options but whatever you use will need some way of adapting the SPDIF to USB card clock domain to the DM7 clock domain.

Michael

Actually the easiest way is to buy an Octo Dac 8 Pro instead of the DM7. The Octo has AES/EBU inputs which are basically SPDIF inputs (just need a cheap SPDIF to AES/EBU transformer). The signal can then be routed to your PC via the AES/USB mode on the OCTO and the computer can then send the LPCM back to the OCTO for final DAC processing. This enables the user, for example, to take a spdif audio from his TV, route it to the OCTO, from there to the PC, do digital processing on it (PEQ, Dirac, high/low pass for subs), send the processed LPCM back to the Octo and from there the the amp(s).

 

[mdsimon2]

Actually the easiest way is to buy an Octo Dac 8 Pro instead of the DM7. The Octo has AES/EBU inputs which are basically SPDIF inputs (just need a cheap SPDIF to AES/EBU transformer). The signal can then be routed to your PC via the AES/USB mode on the OCTO and the computer can then send the LPCM back to the OCTO for final DAC processing. This enables the user, for example, to take a spdif audio from his TV, route it to the OCTO, from there to the PC, do digital processing on it (PEQ, Dirac, high/low pass for subs), send the processed LPCM back to the Octo and from there the the amp(s).

While I agree and have been personally running such a system with an Okto for a few years now, the OP clearly did not want to use a computer. He was of course mis-guided in attempting to use the DM7 without a computer but that was his request. He made this clear in subsequent posts.

I did not need, don‘t have and don‘t want to add a PC in my Audio chain.

My DSP x-over is a DEQX PDC-2.6p with koax and AES Dig.Output option, so a modern multi channel DAC which is affordable like the DM7, but with SPDIF input, would come in handy. But it seems like there is no simple Plug & Play solution.

Sorry, this was not clear from your initial post. You are looking for a multichannel DAC capable of receiving 3 or 4 synced digital outputs from the DEQX, not necessarily a new DSP solution. For all in one options look at the Okto dac8 pro or pro audio offerings like the Lynx Aurora 8.

Does the DEQX do volume control on the digital outputs or do you need that in the DAC? If you don't need volume control then 3 or 4 identical SPDIF input DACs is a perfectly fine solution.

Overall, I think the Okto is a better solution than the DM7 in all use cases. The ability to clock sync with an upstream interface via the AES input as well as provide a clock signal to a separate interface via the AES output gives you good options for making reliable phase measurements when designing DIY active speakers.

The 8 channel AES inputs also give you options for building DIY 5.1/7.1 systems without an AVR. Starting with something like an AppleTV 4K, a VanityPro can convert LPCM HDMI to 8 channel AES or a Dolby Decoder can covert DD to 6 channel AES, once you have 6/8 channel AES it is easily handled by the Okto.

Of course, this comes with a price penalty compared to the Topping DM7 or MOTU UL Mk5 or miniDSP Flex 8/HT/HTx.

The only significant downside to the Okto is the lack of ASRC which makes receiving SPDIF/AES signals from a streamer which dynamically changes sample rates like the Wiim challenging. You either need to restrict your source to a constant sample rate, add an ASRC between the source and Okto or provide some means of detecting the rate change and changing the Okto sample rate to match. Although people complain about the AppleTV ASRC, this is an area where it really shines as you get a consistent 48 kHz output which is easily handled by the Okto.

Michael

 

[soerenssen]

The RME that I linked (and which I use) is a multichannel USB to SPDIF converter (not SPDIF to USB)

You can connect the Wiim's SPDIF output to a PC using a device that has an SPDIF input (such as the MOTU we mentioned already)
This would be the 'SPDIF to USB converter'

As mentioned, this is a bit tricky
Instead, just use the DM7 with your PC as the source

My goal is to somehow keep the Tidal Connect functionality, without having to pay for Roon/Audirvana (for my family it'd be much more convenient instead of using a keyboard/mouse, they know how to use Tidal and got used to it).

Can I connect the WiiM's SPDIF output to the PC via USB using something like this: https://hifimediy.com/product/s2-digi/ ?
The WiiM would be the capture device, routed to the DM7 via another USB.

If it doesn't work, I would replace the WiiM with a Raspberry Pi4 / Hifiberry (solely for Tidal Connect purposes) and connect it to the PC via USB.

 

[ppataki]

My goal is to somehow keep the Tidal Connect functionality, without having to pay for Roon/Audirvana (for my family it'd be much more convenient instead of using a keyboard/mouse, they know how to use Tidal and got used to it).

Can I connect the WiiM's SPDIF output to the PC via USB using something like this: https://hifimediy.com/product/s2-digi/ ?
The WiiM would be the capture device, routed to the DM7 via another USB.

If it doesn't work, I would replace the WiiM with a Raspberry Pi4 / Hifiberry (solely for Tidal Connect purposes) and connect it to the PC via USB.

Theoretically it could work but there might clock drift between the two devices....
Maybe it would be easier to follow @mdsimon2 's point above re. the Okto DAC since it has AES/EBU input

 

[312elements]

It does exist, it is called RME Digiface USB

Digiface USB - RME Audio Interfaces | Format Converters | Preamps | Network Audio & MADI Solutions

RME Audio Professional Live, Studio, Recording and Broadcast Solutions. Unrivalled Quality, Performance & Stability MADI Interfaces, Converters & Preamps.

www.rme-audio.de

It can do USB --> 4x SPDIF out and 4x SPDIF in --> USB
But you will definitely need a PC to make it work, it is not standalone
I highly doubt that there is any standalone device that could do this

I am a happy user of this little beast, I am using it as a multichannel digital-to-digital converter since I have a 4.0 setup in my living room - but of course you can use it for a multi-way stereo setup too

In terms of quality I would highly recommend using a PC as a source and as DSP too since then your options will become limitless - literally

have you had any sync issues with your setup? Do all of the DACs connected have to be the same? Any experience mixing and matching?

 

[ppataki]

have you had any sync issues with your setup? Do all of the DACs connected have to be the same? Any experience mixing and matching?

No sync issue whatsoever
I have not tried connecting different DACs to it
I have three Sabaj A30A connected to it and it works like a charm
Just on another note: next month I will order a miniDSP U-DIO8 just to test it (and to see how it compares to the RME)

 

[312elements]

No sync issue whatsoever
I have not tried connecting different DACs to it
I have three Sabaj A30A connected to it and it works like a charm
Just on another note: next month I will order a miniDSP U-DIO8 just to test it (and to see how it compares to the RME)

If I decide to move forward I'll report back on mixing dacs and sync issues. My hope (expectation) is that the RME will have significantly better jitter management and the minidsp.

 

[ppataki]

My hope (expectation) is that the RME will have significantly better jitter management and the minidsp.

I am not sure...if you check the measurements of the U-DIO8 the jitter was 800ps - that is the same that is stated in the specs of the RME too

 

[312elements]

That's a bummer @ppataki . Looks like Motu has a similar device as well (LP32)

 

[ppataki]

That's a bummer @ppataki . Looks like Motu has a similar device as well (LP32)

Yes, but for twice the price....
And no measurements or adequate specs (that I am aware of at least)

 

[wgh52]

OK Folks,

being the one having kicked all this off, I'd like to describe the configuration I'm in the middle of implementing:

Three DSP boxes are "in charge".
Box 1 is an openDRC DI in a larger case which also contains linear power supply and an ADC board. The miniSHARC and the ADC board are clocked by a Tentlabs XO3.2. This box is a pre processor for room correction, room curve and personal taste implementation (IIR and FIR filtering). Box 1 is placed with the sources in a rack.

Box 2 and 3 are mounted one each on the back side of my active DIY Speakers (with 4-Way analog Inputs) implementing the x-over functions plus overall Phase- and Frequency response linearization (IIR & FIR with Acourate). They get their SPDIF input signal from Box 1 via BNC Coax cables (I may go Toslink at some point). These boxes are both openDRC DI, with two Khadas DAC boards built into each case for up to 4-Way Output. miniSHARC and DAC boards are clocked by Neutrino Clocks. (Linear) Power supply comes from a separate small box also mounted on the back side of the speaker.

Still lots of work to do, but I feel confident to make it work

Thanks for all the input and advice!
Winfried

PS: By the way: The DEQX PDC stopped working, too expensive to repair, so I build my own solution

 

[312elements]

No sync issue whatsoever
I have not tried connecting different DACs to it
I have three Sabaj A30A connected to it and it works like a charm
Just on another note: next month I will order a miniDSP U-DIO8 just to test it (and to see how it compares to the RME)

Any chance you've got an overview of your setup posted here (software/hardware/etc). Looking through some of your posts it appears we have similar taste and I'm generally curious about how you managed to get everything to work together.

 

[ppataki]

Maybe this would help:

Multichannel Full Digital Amp (FDA) solution

I thought I would share my experience and learning here; hopefully it will inspire others too. I have been fascinated by the concept of a Full Digital Amp (FDA) ever since early models started to appear; I even had a pair of active monitors using FDAs (Nubert nuPro A-300) But I have always...

www.audiosciencereview.com