Please help me clear some questions >> multichannel DAC for HT use.

[mga2009]

Hi,

I recently sold my receiver and started experimenting with an HDMI 8 channel DAC to DSP and then to amplifiers. Results were very satisfactory but I might be getting some SQ loses in the duplicate ADC - DAC conversion as I've got the DIGITAL to ANALOG from the HDMI DAC, and then again the ADC and DAC of the DSP... so I think I can't get rid of that If I use my computer as a sole source form y media, so I can use it as DSP and also allows me to use a high quality DAC to feed my amplifiers.

I am thinking this:

PC > USB > HIGH QUALITY 8 CHANNEL (OR MORE) DAC >> AMPLIFIERS

For High quality DAC I have the following choices:
-. OktoDAC8 Pro
-. Motu Ultralite MK4 (or similar)
-. miniDSP DDRC-88A

My questions regarding those DACs are:

-. I connect them with USB to my PC, and I willl be able to route/manage all 8 channels independently? I ask because I've experimented with some lower end USB interfaces and there is always a driver problem to output all channels at once and also having control over them (for PEQ, XEO, etc.)

-. Can I use 2 (or more) USB interfaces (very same model) simultaneously to my PC for "doubling" the channels? Just in the case I wanted to go with active XO and needed the extra output channels or if in the future people got a way to decode object based audio by software and needed more than 8 channels...

-. Can I use any software (like EQ APO) to manage the interfaces or do I need a specific branded software? Will this branded software be compatible with PC's video players like Potplayer or JRiver?

-. Can I input 8 analog channels to my interface, process it, and then output thru the DAC in real time without too much delay? That way I might be able to also use another media source, although I suspect SQ would be worse as I would be adding a DAC before the ADC of the interface.

This setup would be used strictly for home theater/gaming use, just in case anyone cares.

Looking forward to you help and knowledge.

Cheers.

 

[Blumlein 88]

On Windows you'll run into problems using two devices.

Listen to the 8th generation loopbacks I've posted. I think a single extra ADC step is nothing to worry about using high quality devices like you have.

https://www.audiosciencereview.com/...-choose-the-8th-generation-digital-copy.6827/

https://www.audiosciencereview.com/...dac-loop-vs-the-original-can-you-hear-it.448/

 

[mga2009]

On Windows you'll run into problems using two devices.

Listen to the 8th generation loopbacks I've posted. I think a single extra ADC step is nothing to worry about using high quality devices like you have.

https://www.audiosciencereview.com/...-choose-the-8th-generation-digital-copy.6827/

https://www.audiosciencereview.com/...dac-loop-vs-the-original-can-you-hear-it.448/

Thanks for your reply!

Well, actually now I don't have "high quality" devices.... the HDMI DAC is a Cirrus Logic 4353 and the DSP I am using is the Analog Devices 1701 and Analog Devices 1452.

You say "in Windows" I will run into problems... where I am not? Linux? OSX?

I will check the 8th gen loopbacks carefully to see If I notice something!

 

[Blumlein 88]

Mac will run more than one audio device just fine. It is the easiest way to do this if you want to do so.

 

[mga2009]

Mac will run more than one audio device just fine. It is the easiest way to do this if you want to do so.

Thanks, will consider OSX as an option.

Regarding the other questions, If I stay with 1 device, is it possible to use it for HT, with PEQ, room eq, etc. capabilities?

 

[Blumlein 88]

Thanks, will consider OSX as an option.

Regarding the other questions, If I stay with 1 device, is it possible to use it for HT, with PEQ, room eq, etc. capabilities?

Too many variables for me to give you an answer of any help. I'll say maybe, but I don't know how myself.

 

[somebodyelse]

Linux is fine with multiple devices too, but whatever the OS there's potential for multiple devices to drift out of sync if you don't link them with a master clock. That's a feature that you'll probably only find on pro audio interfaces, but many of those don't have linux drivers.

How are you decoding the multichannel audio for HT?

 

[mga2009]

Linux is fine with multiple devices too, but whatever the OS there's potential for multiple devices to drift out of sync if you don't link them with a master clock. That's a feature that you'll probably only find on pro audio interfaces, but many of those don't have linux drivers.

How are you decoding the multichannel audio for HT?

The only caveat for my usage of OSX and Linux is that they offer a very poor gaming experience... that's why Windows is my main target.

I've read some people claim that connecting two USB interfaces with ADAT, the second one syncs with the master clock (interface connected thru USB to my PC)... the thing is that other people claim this is not possible. Don't know who believe.

I think the decoding is done in the video player thru FFMPEG... right now I get LPCM to my HDMI DAC > DSP

 

[Blumlein 88]

I've read some people claim that connecting two USB interfaces with ADAT, the second one syncs with the master clock (interface connected thru USB to my PC)... the thing is that other people claim this is not possible. Don't know who believe.

It is true you can connect two interfaces with one going via ADAT to the one connected to the PC. The secondsry one will not be connected via USB and you have to set the input and output routing while connected, and then disconnect it to run as a stand alone device. So your connected interface will have routing of those ADAT signals, but you'll not have any other control over the secondary device. Some secondary devices will allow you control from the front panel even then, while others work differently and your settings are simply fixed to however you last left them.

 

[mga2009]

It is true you can connect two interfaces with one going via ADAT to the one connected to the PC. The secondsry one will not be connected via USB and you have to set the input and output routing while connected, and then disconnect it to run as a stand alone device. So your connected interface will have routing of those ADAT signals, but you'll not have any other control over the secondary device. Some secondary devices will allow you control from the front panel even then, while others work differently and your settings are simply fixed to however you last left them.

Thanks for that info!

By "not have control" you mean levels, peq, delay, xo, etc.? Maybe I can connect it to another PC (laptop) to control it if I need... the thing is if when disconnected from the PC it retains the saved configuration, much like working as a stand alone DSP (i am pretty sure not all interfaces can do this).

 

[Blumlein 88]

Thanks for that info!

By "not have control" you mean levels, peq, delay, xo, etc.? Maybe I can connect it to another PC (laptop) to control it if I need... the thing is if when disconnected from the PC it retains the saved configuration, much like working as a stand alone DSP (i am pretty sure not all interfaces can do this).

Most, but not all interfaces will work stand alone disconnected from a PC.

And yes, you'll not have software control over PEQ, delay, any number of things. You could in fact use a 2nd PC for that. But for playback of music or movies you've created quite the frankenstein device if you go that route.

 

[somebodyelse]

The only caveat for my usage of OSX and Linux is that they offer a very poor gaming experience... that's why Windows is my main target

Decent reason - Proton has certainly improved thigns, but it's not great.

I've read some people claim that connecting two USB interfaces with ADAT, the second one syncs with the master clock (interface connected thru USB to my PC)... the thing is that other people claim this is not possible. Don't know who believe.

It probably depends on the interface and the controls it exposes. If the second interface lets you select the ADAT input as the clock source then it might work. I think you can do something similar to sync the old M-Audio Delta/Audiophile cards via the SPDIF ports but I've never had reason to try it. I assume the MOTU AVB devices sync via the network if you use a compatible router.

I think the decoding is done in the video player thru FFMPEG... right now I get LPCM to my HDMI DAC > DSP

So limited to AC3 or DTS still I assume - AFAIK the more advanced formats only work as passthrough, although i live in hope!

 

[mga2009]

Decent reason - Proton has certainly improved thigns, but it's not great.

It probably depends on the interface and the controls it exposes. If the second interface lets you select the ADAT input as the clock source then it might work. I think you can do something similar to sync the old M-Audio Delta/Audiophile cards via the SPDIF ports but I've never had reason to try it. I assume the MOTU AVB devices sync via the network if you use a compatible router.

So limited to AC3 or DTS still I assume - AFAIK the more advanced formats only work as passthrough, although i live in hope!

Really? I thought FFMPEG decoded also more advanced formats, excluding object based. So, what I am actually hearing when I launch a Bluray backup (MKV format) in POTplayer or JRIVER? Just a compressed version of the TrueHD soundtrack?

 

[somebodyelse]

Really? I thought FFMPEG decoded also more advanced formats, excluding object based. So, what I am actually hearing when I launch a Bluray backup (MKV format) in POTplayer or JRIVER? Just a compressed version of the TrueHD soundtrack?

I'm not certain so I was hoping you might have better info than me - it could be that the documentation I've found just hasn't caught up with new capabilities, since writing the code is more fun than updating the ducumentation The ffmpeg codec page doesn't list DTS at all, although 'ffmpeg -codecs' has it. The VLC formats page suggests it decodes DTS Core only, and that for DTS-HD it extracts the DTS Core and only decodes that.

 

[Vasr]

Hi,
so I think I can't get rid of that If I use my computer as a sole source form y media, so I can use it as DSP and also allows me to use a high quality DAC to feed my amplifiers.

I am thinking this:

PC > USB > HIGH QUALITY 8 CHANNEL (OR MORE) DAC >> AMPLIFIERS

You may find my detailed notes on this useful. It is possible to do what you are thinking. I would stick to Windows for availability of third party software especially free ones.

https://www.audiosciencereview.com/...ring-a-pc-as-a-8-ch-pre-pro-experiment.14785/

For High quality DAC I have the following choices:
-. OktoDAC8 Pro
-. Motu Ultralite MK4 (or similar)
-. miniDSP DDRC-88A

You can use any of them. What you want to avoid is having the overall volume be controlled only from within the PC in software. It is asking for trouble as there are many scenarios in which the volume can be bumped up to max inadvertently. Having a hardware volume in the chain is preferable. So that rules out the Motu whose hardware volume control only applies to the main 2 channels and the rest is controlled by input volume.

Okto is great for this and you can offload channel balancing to it (although it can be done fairly easily within the PC).

miniDSP DDRC-8A has Dirac but involves a ADC-DAC stage. DDRC-8D avoids the latter but its connectivity is a pain. You need an additional $300 dongle just to get USB into it.

Dirac can be done in the PC itself as explained in my notes.

So the Okto is really the best bet amongst these. Unless you need some of the pro features of the Motu.

-. Can I use 2 (or more) USB interfaces (very same model) simultaneously to my PC for "doubling" the channels? Just in the case I wanted to go with active XO and needed the extra output channels or if in the future people got a way to decode object based audio by software and needed more than 8 channels...

In theory, yes. But there are two issues. One is timing issues between the two. Small fixed relative delays can be offset but there is no guarantee they will not get out of sync while playing. Second is what you would use to route from a source that outputs more than 8 channels to split it between the two devices. You can use Equalizer APO to do some rudimentary routing but something has to be able to split a 8+ channel stream and more likely you need one of the Pro Audio boxes with their software to handle this. They are designed to handle a large number of channels and their routing with minimum latency.

-. Can I use any software (like EQ APO) to manage the interfaces or do I need a specific branded software? Will this branded software be compatible with PC's video players like Potplayer or JRiver?

See my notes on how to set this up system wide so any application can use the DSP/Crossover/Balance/Delay processing.

-. Can I input 8 analog channels to my interface, process it, and then output thru the DAC in real time without too much delay? That way I might be able to also use another media source, although I suspect SQ would be worse as I would be adding a DAC before the ADC of the interface.

I am not sure what you mean by interface above. If you mean the PC interface, getting multi-channel audio into it is a pain. Windows is not designed for it and in some cases works against it (no Windows audio device can be more than 2 channels for input, for example after Windows XP). So you will need something that can act as an audio source via USB externally, and provides drivers/software to use on the computer to do direct ASIO bypassing Windows limitations. Again Pro audio equipment/software are better for this.

This setup would be used strictly for home theater/gaming use, just in case anyone cares.

The major caveat for this is to understand that all of this works for playing content with multiple channels that is not DRM protected. Since the above set up will not be HDCP compliant. So streaming commercial content that has DRM will not work with the processing done above. Ripped content to your drives/NAS or content without DRM is fine. This is the main drawback of this approach.

Gaming is typically not as much of a problem as the reliance on DRM is far less for audio output.

 

[mga2009]

You may find my detailed notes on this useful. It is possible to do what you are thinking. I would stick to Windows for availability of third party software especially free ones.

https://www.audiosciencereview.com/...ring-a-pc-as-a-8-ch-pre-pro-experiment.14785/


You can use any of them. What you want to avoid is having the overall volume be controlled only from within the PC in software. It is asking for trouble as there are many scenarios in which the volume can be bumped up to max inadvertently. Having a hardware volume in the chain is preferable. So that rules out the Motu whose hardware volume control only applies to the main 2 channels and the rest is controlled by input volume (...)

Thanks for your reply! Tons of great information! I have read the other thread several times, and did not find what is exactly your audio setup. Are you using just a soundcard as DAC? I know you are using a CMEDIA soundcard for SPDIF input (2 channels only) to the PC. Maybe I just missed it.

Also, why the use of Voicemeeter Banana? I know its a "virtual" mixer, and have use it occasionally. But, in this case, does this replace the Windows Mixer? I know Windows Mixer is bypassed when using ASIO or Wasapi (in direct mode) thus there is no way to use E-APO (leaving Jriver DSP as the "best" choice for audio without upsampling/downsampling)

The Dirac Live Processor for Windows multichannel standalone costs USD$500, and that's pretty close to the cost of used NAD 758 v3 AVR. Is it really worth it? From your comments I assume it is... Have you tried using the VST plugin directly on Equalizer APO?

 

[gene_stl]

I have been watching this thread. I have not done any of this yet but a correspondent I have at Quadrophonic Quad pointed me to the following devices which may well be applicable.

https://www.esi-audio.com/products/gigaporthd+/ retail approx $115 up to 96 kHz

https://www.esi-audio.com/products/gigaportex/ retail approx $200 up to 192kHz USB 3.1

above made in Chermany I love the pricing. Software bundled too. Unbalanced outputs.

https://store.focusrite.com/en-gb/product/scarlett-18i20-2nd-gen/MOSC0015UKEUDM~MOSC0015UKEUDM
Focusrite $304

I have not tried any of these. I will probably try one of the second two before long.

 

[Vasr]

Thanks for your reply! Tons of great information! I have read the other thread several times, and did not find what is exactly your audio setup. Are you using just a soundcard as DAC? I know you are using a CMEDIA soundcard for SPDIF input (2 channels only) to the PC. Maybe I just missed it.

I was using the soundcard just to get the SPDIF in from an external source so I could use the crossover in EAPO and output 2.1. Now I am using an external DAC and a crossover, so that is no longer necessary. Analog out of a soundcard in my system has serious ground loop problems.

Also, why the use of Voicemeeter Banana? I know its a "virtual" mixer, and have use it occasionally. But, in this case, does this replace the Windows Mixer? I know Windows Mixer is bypassed when using ASIO or Wasapi (in direct mode) thus there is no way to use E-APO (leaving Jriver DSP as the "best" choice for audio without upsampling/downsampling)

Voicemeeter was necessary for two things. One for getting the SPDIF in and then passing it through EAPO for the crossover and to route the 2.1 to the downstream DAC. This is not necessary anymore for me as above. The other reason is to hook up Dirac VST running VST Host, there is no other reliable way to do it as a system-wide room eq with multi-channels. You can have Voicemeeter doing WASAPI or ASIO to the output device bypassing the Windows mixer but attach EAPO to the Voicemeeter virtual input and have the media players output to that in non-exclusive mode.

The Dirac Live Processor for Windows multichannel standalone costs USD$500, and that's pretty close to the cost of used NAD 758 v3 AVR. Is it really worth it? From your comments I assume it is... Have you tried using the VST plugin directly on Equalizer APO?

Getting reliable used equipment is an unknown quantity. Multi-channel Dirac on the PC is cheaper than buying multi-channel Dirac enabled hardware new. miniDSP solutions notwithstanding because of their ridiculous connector choices or extra ADC-DAC conversion depending on which one of them you use.

There are limitations on what VSTs can be used with EAPO. The main one for using something like Dirac Live Processor VST is that EAPO (unlike VST hosts) as far as I know has no mechanism to display any user interfaces (for settings) provided by the VST. So, I didn't even try it and have no idea if it will even work that way.

 

[dualazmak]

Hi,

I recently sold my receiver and started experimenting with an HDMI 8 channel DAC to DSP and then to amplifiers. Results were very satisfactory but I might be getting some SQ loses in the duplicate ADC - DAC conversion as I've got the DIGITAL to ANALOG from the HDMI DAC, and then again the ADC and DAC of the DSP... so I think I can't get rid of that If I use my computer as a sole source form y media, so I can use it as DSP and also allows me to use a high quality DAC to feed my amplifiers.

I am thinking this:

PC > USB > HIGH QUALITY 8 CHANNEL (OR MORE) DAC >> AMPLIFIERS

For High quality DAC I have the following choices:
-. OktoDAC8 Pro
...
...

I hope my successful multichannel multi-amplifier project with software crossover EKIO and DAC8PRO would be a valuable reference for you...

 

[dualazmak]

You may hopefully use two of DAC8PRO simultaneously to enable 16 channel output;
https://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-okto-dac8-8ch-dac-amp.7064/post-450063

I would like to suggest you to carefully read through the DAC8PRO review thread, and my multichannel thread, for your reference.

I believe all of your demands can be achieved digitally in one Windows 10 PC using very flexible ASIO I/O routings using ASIO4ALL, VB Audio Hi-Fi Cable, and software cross over like EKIO, as shown here.

I can/could actually use multiple DACs, DAC8PRO, OPPO SONICA DAC and ONKYO DAC-1000, simultaneously with EKIO's very much flexible unlimited number of output channels, even though the minor synchronization issue remains for different ASIO connections; in my experience, I do not have major "out of sync" problem even when listening to rather long track, ca. 30 min to 60 min.