Topping DM7 8-Channel DAC Review

[sarumbear]

I would have thought the basis of a review of any consumer product is, based on who or what the product is designed for, will it meet their expectations? When you don't even know who or what the product is for, you can't even start to assess it.

What is a DAC for? Answer that to yourself and than think of scenarios where multiple power amplifiers are used. You will get there.

 

[mdsimon2]

Topping could just add SPDIF input and that was that. So no need for ASRC unless you’ve some other requirements.

It’s not that simple. A stereo SPDIF input is of little value on an 8 channel DAC unless you have DSP to expand that to 8 channels of output.

With a USB DAC the simplest way to do this is to add the ability to route that SPDIF input signal to the USB host, do processing on the host and then route the processed signal back to the DAC. This looks something like the Okto AES/USB mode or what is offered by interfaces. This is a much more complex product.

You could also do something like the Okto where you have 4x stereo digital inputs but that adds it’s own complications. What are the clocking requirements on those inputs (Okto has trouble with some sources when using all 8 channels over AES)? There are also not many processors available with 4x stereo outputs.

To me I think the Topping makes a lot of sense as is. Very good measured performance, it offers IR volume control / indication which is only offered on the Exasound and Okto at a much higher price point. If some wants stereo digital inputs or additional sources you can do this relatively easily. Biggest issue to me is $600 is a lot to spend on something that may not have the best support.

Michael

 

[Trell]

I was looking at the product website to see who or what it was designed for. No luck.

I assumed it was an external DAC for an AV system, but others point out that the lack of connectivity and software means you have to attach a laptop, you can't attach a normal consumer AV source product.

I would have thought the basis of a review of any consumer product is, based on who or what the product is designed for, will it meet their expectations? When you don't even know who or what the product is for, you can't even start to assess it. Most of the comments in this thread are questioning who or what it is for.

@Glitch at ±176 aove summarises is much better than me: "The 120dB SINAD is great and worth the asking price, except in practical terms a well implemented 8ch DSP with 96dB SINAD and various inputs is much more valuable. It's as if Topping is playing to their strengths without addressing practical uses."

The product is not for you and I dare say you don’t understand why.

 

[sarumbear]

What the world needs is a Raspberry Pi running an opensource software that supports all codecs, receiving HDMI eARC input and sending multichannel audio in its USB output, with a web interface to set up channel levels, high/low pass filters and even some PEQ or room correction.

Then we would have a great solution for TV => Raspberry Pi decoding => multichannel DAC => multichannel amp for our home theaters.

There’s no consumer codec available for spatial audio (Atmos, etc.)

 

[Trell]

It’s not that simple. A stereo SPDIF input is of little value on an 8 channel DAC unless you have DSP to expand that to 8 channels of output.

With a USB DAC the simplest way to do this is to add the ability to route that SPDIF input signal to the USB host, do processing on the host and then route the processed signal back to the DAC. This looks something like the Okto AES/USB mode or what is offered by interfaces. This is a much more complex product.

You could also do something like the Okto where you have 4x stereo digital inputs but that adds it’s own complications. What are the clocking requirements on those inputs (Okto has trouble with some sources when using all 8 channels over AES)? There are also not many processors available with 4x stereo outputs.

To me I think the Topping makes a lot of sense as is. Very good measured performance, it offers IR volume control / indication which is only offered on the Exasound and Okto at a much higher price point. If some wants stereo digital inputs or additional sources you can do this relatively easily. Biggest issue to me is $600 is a lot to spend on something that may not have the best support.

Michael

But the device does not have SPDIF, so what am I missing apart that you want more digital inputs?

 

[Atanasi]

Does this mean that TR connectors can not be used? How should one then connect to unbalanced equipment?

Probably it means that unbalanced connections are not directly supported. It needs adapters like this:

TRS-2xRCA cables are readily available. The white side connects to the positive pole, and the other pole is left floating. Female RCAs are preferred, so that the connectors are not touched by accident.

 

[MCH]

Sure, hit me up after you have it all figured out and have debugged all the problems, I'll be interested.

RPi4 + CamillaDSP Tutorial

Intent of this thread is to provide a tutorial for setting up CamillaDSP on a RPi4. There is a lot of good information scattered through ASR, DIYAudio and the CamillaDSP GitHub but there also appears to be a lot of apprehension. My goal is to give concrete examples of how to use CamillaDSP with...

audiosciencereview.com

Have it working strong as a rock since months.

 

[Rednaxela]

DAC

Perhaps just call it a sound card.

 

[mdsimon2]

But the device does not have SPDIF, so what am I missing apart that you want more digital inputs?

You were the one that asked for Topping to include a SPDIF input, not me.

Topping could just add SPDIF input and that was that. So no need for ASRC unless you’ve some other requirements.

We might be speaking past each other. I think the DM7 is fine as-is. I just described how you could add a SPDIF input for less than $50 if wanted, that is all.

For all those lamenting the lack of physical inputs if you are running CamillaDSP it is very easy to add a SPDIF input with a device like this -> https://hifimediy.com/product/s2-digi/. Just set the hifimediy as your capture device and the DM7 as your playback device and enable async resampling and rate adjust and CamillaDSP will bridge the clock domains. Poor man’s Okto at half the price.

Michael

 

[sarumbear]

…object-based encodings aren't that common. In fact, a nontrivial player in the space, Auro 3d, recently declared bankruptcy.

There are almost no films released without Atmos. Here in the UK the HT installation market is 100% spatial.

Auto 3D failed because they started as a music format and have not made inroads to Hollywood. Eventually, Surround Audio died so have their market. Dolby on the other hand is a film format, which means their format is always alive.

 

[dwkdnvr]

If some wants stereo digital inputs or additional sources you can do this relatively easily.

Michael

I'm now wondering how hard it would have been to add a word-clock output to this. Slaving an external A/D or even a D/D interface (like the old Behringer SRC2496) would pretty much solve most of the limitations I see with this device. You could even slave an additional studio interface for additional output channels if needed.

 

[sarumbear]

I'm now wondering how hard it would have been to add a word-clock output to this. Slaving an external A/D or even a D/D interface (like the old Behringer SRC2496) would pretty much solve most of the limitations I see with this device. You could even slave an additional studio interface for additional output channels if needed.

Do you mind listing your limitations v

 

[sarumbear]

RME has that in their (audio) interfaces and the GUI for using that is called TotalMix but it's just a front end to the hardware capabilities. It's very handy and useful. I'm using it in video calls where one mic output is delayed 300ms for lip synch while monitoring is in real time. No DAW needed or wanted, and would just be a hassle. With 10ms increments it's that useful for multi channel setups.

The functionality is not free, though, but a major selling point.

Shouldn’t that be done at OS level?

 

[mdsimon2]

RPi4 + CamillaDSP Tutorial

Intent of this thread is to provide a tutorial for setting up CamillaDSP on a RPi4. There is a lot of good information scattered through ASR, DIYAudio and the CamillaDSP GitHub but there also appears to be a lot of apprehension. My goal is to give concrete examples of how to use CamillaDSP with...

audiosciencereview.com

Have it working strong as a rock since months.

I imagine this will be very easy to use in a RPi4 / CamillaDSP setup. None of the weirdness that some audio interfaces have with changing channel counts based on sample rates.

Overall I've had very good luck with multichannel interfaces on Linux. I saw Focusrite mentioned earlier as not working on Linux but I had an 18i20 2nd gen that worked perfectly. Only interfaces I've run in to recently with issues are MOTU AVB interfaces. Otherwise I've successfully used the Okto dac8 pro, MOTU M4, MOTU Ultralite Mk5, DIYINHK ES9016/9038, miniDSP USB streamer with a variety of ADAT DACs and Focusrite 18i20 2nd gen on modern versions of Ubuntu and a RPi4.

Michael

 

[Atanasi]

But the device does not have SPDIF, so what am I missing apart that you want more digital inputs?

One useful feature is S/PDIF as a clock source while sending audio through USB. This allows combining multiple DACs for even more channels while keeping them all synchronized to the same clock.

 

[Trell]

You were the one that asked for Topping to include a SPDIF input, not me.

I wrote it would nice if Topping included more digital inputs but that was for multichannel ones, but then price of course would increase. A trade off.

That still does but explain why you need ASRC, whence my question.

 

[Trell]

One useful feature is S/PDIF as a clock source while sending audio through USB. This allows combining multiple DACs for even more channels while keeping them all synchronized to the same clock.

Ah, I assumed an either/or situation with use of digital inputs.

 

[dwkdnvr]

Do you mind listing your limitations v

I did earlier.
a) no inputs to allow integrating external sources such as TV etc
b) no ability to add clock-sync'd additional channels in case 8 isn't enough. (e.g. 7.1 surround with 3-way DSP mains needs 12 channels)

As mdsimon points out there are some specific scenarios where you can deal with a) using adaptive asrc under linux, but the output side is trickier. A word clock output would more or less allow solving both by adding an external studio interface, but the majority of audio users would be perplexed by it.

 

[sarumbear]

I did earlier.
a) no inputs to allow integrating external sources such as TV etc
b) no ability to add clock-sync'd additional channels in case 8 isn't enough. (e.g. 7.1 surround with 3-way DSP mains needs 12 channels)

a) you describe a device that has other functionalities than what a simple DAC will have. An analogy will be asking multiple input on a power amplifier.

b) this is a consumer device designed to operate by itself.

The above is not a limitation of an 8-ch DAC. You want a different equipment, which this device is not.

 

[pos]

I wrote it would nice if Topping included more digital inputs but that was for multichannel ones, but then price of course would increase. A trade off.

That still does but explain why you need ASRC, whence my question.

Having multiple digital inputs is more complicated than it might look.
You need to have a common clock for the inputs and outputs, which means you either need to use one of the inputs as clock source (eg what the RME digiface does) or have an ASRC on each input to convert to your internal clock (eg what the minidsp UDIO8 does).
The second solution is arguably better when done properly, but more costly as it requires one ASRC chip per stereo pair.
The first solution on the other hand implies that all you inputs have to use the same clock (ie come from the same device, of fed from the same wordclock source).

I like the fact that the DM7 is only focused on outputs: it makes things simpler and helps keeping the cost low.
It is less versatile than an Okto for sure, but what it does it seems to do it right.