TOPIC:

Hi everyone,

I want to convert analog 7.1 surround sound (from my home hifi) into digital for feeding into DDRC-88D.

I don't want the DDRC-88A, because I want to use my own DACs and DSP XO after the Dirac box, so I need the DDRC-88D.

I thought it would be a simple matter to shop and buy 8 channels of good-performance, reasonably-priced ADC that has digital output compatible with the DDRC-88D inputs. Either one box with 8 channels, or 4 stereo ADC units.

But I am having a terrible time finding anything suitable. I thought a pro audio audio interface would do it, but they seem to have analog out, or USB out for feeding into a DAW, but no direct output in the right format for feeding into the DDRC-88D.

How am I supposed to do this? Any suggestions would be great.

Professional 8 channel converters will be very expensive, but they do exist...

Genelec AD9002A . . . . . . . . . . . . £559.00 ( you would need to get XLR x4 to 25pin D-sub loom cables, but it would work)
RME ADI 8 DS MKIII . . . . . . . . . . £1,336.48
Mytek Digital 8x192 . . . . . . . . . . £2,130.88
Lynx Aurora n8 + LM-DIG . . .. . £3098.00
Prism Sound ADA-8XR . . . . . . . . £8146.80

Another approach would be to look for a cheaper priced multichannel converter that does 8-channel analogue A/D to ADAT optical digital output (of which there are numerous to choose from Behringer, ART, Presonus, Focusrite, Ferrofish, Antelope, Alesis, etc.) then pick up an external digital format converter box from ADAT optical to the required AES/EUB 25 pin D-sub. (eg. Mutec MC4 or RME ADI-4 DD )

Neither is a very elegant or simple solution. Don't you have any way of getting your 7.1 surround material directly from digital source somehow rather than going to analogue and back to digital again for further DSP ?

It's a pity miniDSP can't include ADAT optical as one of the digital formats they offer, since they do already have Toslink optical for S/PDIF, and they already do make the USBStreamer product which includes switchable ADAT or S/PDIF optical.
I'm sure it's not an insurmountable technical hurdle for them to get the Alesis license and implement the circuitry to handle ADAT as well as S/PDIF optical.
Vast majority of popular pro / semi-pro products these days tend to use ADAT rather than AES/EBU D-sub because it's much cheaper (especially with cost of looms and particular screwthreads or wiring conventions vs very low cost of optical cables) and less messy, and also it avoids electrical ground loop issues or static shock problems.

.AJA ADA4 convert 2 aes/ebu to 4 analog or vice versa. Around $400 each but you can get them fir about half that.

Richard wrote:

Professional 8 channel converters will be very expensive, but they do exist...

Genelec AD9002A . . . . . . . . . . . . £559.00 ( you would need to get XLR x4 to 25pin D-sub loom cables, but it would work)

This is the only one in a price range for me, but I cannot find it by internet search. Can you help?

RME ADI 8 DS MKIII . . . . . . . . . . £1,336.48
Mytek Digital 8x192 . . . . . . . . . . £2,130.88
Lynx Aurora n8 + LM-DIG . . .. . £3098.00
Prism Sound ADA-8XR . . . . . . . . £8146.80

Another approach would be to look for a cheaper priced multichannel converter that does 8-channel analogue A/D to ADAT optical digital output (of which there are numerous to choose from Behringer, ART, Presonus, Focusrite, Ferrofish, Antelope, Alesis, etc.) then pick up an external digital format converter box from ADAT optical to the required AES/EUB 25 pin D-sub. (eg. Mutec MC4 or RME ADI-4 DD )

Neither is a very elegant or simple solution. Don't you have any way of getting your 7.1 surround material directly from digital source somehow rather than going to analogue and back to digital again for further DSP ?

I would love to get it direct from digital, if you have any suggestions how one de-embeds uncompressed 7.1 audio from consumer HDMI audio out of a bluray player or AV receiver, in a format suitable for a miniDSP Dirac product? I have looked far and wide for such a solution, and it would be my first choice.

It's a pity miniDSP can't include ADAT optical as one of the digital formats they offer, since they do already have Toslink optical for S/PDIF, and they already do make the USBStreamer product which includes switchable ADAT or S/PDIF optical.
I'm sure it's not an insurmountable technical hurdle for them to get the Alesis license and implement the circuitry to handle ADAT as well as S/PDIF optical.
Vast majority of popular pro / semi-pro products these days tend to use ADAT rather than AES/EBU D-sub because it's much cheaper (especially with cost of looms and particular screwthreads or wiring conventions vs very low cost of optical cables) and less messy, and also it avoids electrical ground loop issues or static shock problems.

Yes, but all a bit speculative for my immediate problem.

Thanks for your thoughts.

rhollan wrote:

AJA ADA4 convert 2 aes/ebu to 4 analog or vice versa. Around $400 each but you can get them fir about half that.

I had not seen that before, thank you, it looks very promising. 24/96 is fine, pity there is no spec on the input analog SNR.

Currently this looks like my best option.

Yes, I feel your frustration having been through a similar process about two years ago.

I found two acceptable solutions although I did not look extensively into the pro sector.

I discovered Arvus products after I had selected my current solution and the HDMI-2A would have been ideal.

So, I found a website offering after market modification of Oppo BDPs and Octava HDMI matrix units and needing a Blu-ray player I chose the Oppo Vanity card modification. Of course, that was before Oppo pulled out of the audio market.

In your case, the Octava may appeal but check out the Current website for the latest.

alandbush wrote:

Yes, I feel your frustration having been through a similar process about two years ago.

I found two acceptable solutions although I did not look extensively into the pro sector.

I discovered Arvus products after I had selected my current solution and the HDMI-2A would have been ideal.

So, I found a website offering after market modification of Oppo BDPs and Octava HDMI matrix units and needing a Blu-ray player I chose the Oppo Vanity card modification. Of course, that was before Oppo pulled out of the audio market.

In your case, the Octava may appeal but check out the Current website for the latest.

Arvus HDMI 2A is £2375 last time I checked. I bit too Spendy for me.

nowater57 wrote:

Genelec AD9002A . . . . . . . . . . . . £559.00
This is the only one in a price range for me, but I cannot find it by internet search. Can you help?

www.musicstore.de/en_GB/GBP/Genelec-AD92...r/art-REC0007204-000

nowater57 wrote:

I would love to get it direct from digital, if you have any suggestions how one de-embeds uncompressed 7.1 audio from consumer HDMI audio out of a bluray player or AV receiver, in a format suitable for a miniDSP Dirac product?

Unlikely to find cheap consumer hardware device that does this, as the market for such a device would be very small with typical consumers. The professional Avrus HDMI-2A will do it for a hefty price.
However, I was thinking more that you could play the Blu-Ray disc on a computer instead, and just route the 7.1 audio output paths to an external USB soundcard / audio interface which has whatever digital audio format connections you require, or maybe ADAT out to an external DAC solution.

Richard wrote:

nowater57 wrote:

Genelec AD9002A . . . . . . . . . . . . £559.00
This is the only one in a price range for me, but I cannot find it by internet search. Can you help?

www.musicstore.de/en_GB/GBP/Genelec-AD92...r/art-REC0007204-000

nowater57 wrote:

I would love to get it direct from digital, if you have any suggestions how one de-embeds uncompressed 7.1 audio from consumer HDMI audio out of a bluray player or AV receiver, in a format suitable for a miniDSP Dirac product?

Unlikely to find cheap consumer hardware device that does this, as the market for such a device would be very small with typical consumers. The professional Avrus HDMI-2A will do it for a hefty price.
However, I was thinking more that you could play the Blu-Ray disc on a computer instead, and just route the 7.1 audio output paths to an external USB soundcard / audio interface which has whatever digital audio format connections you require, or maybe ADAT out to an external DAC solution.

Heh. I am doing exactly this. Better universal players (like the Oppo 10x and 20x series) have a secondary HDMI output, designed to carry audio. Apparently, they will provide 7.1 LPCM audio over black video with no HDCP. (You configure the audio as either bitstream or LPCM, and, in the latter case, the Oppo decodes bitstream formats like TruHD, etc.) I suppose you could split off such a signal from an existing encrypted HDMI signal with something like an HDFury AVRKey. In any case, you can run that through an HDMI to SDI converter (SDI is a professional video format that carries uncompressed digital video over a single 75 ohm coax cable), and thence to an SDI audio de-embedder, Black Magic makes both kind of devices. Look up their mini and micro converters. Two boxes (under $100 for HDMI to SDI, and under $200 for SDI audio de-embedder) will give you 4x 2ch digital AES/EBU audio on balanced TRS connectors.

www.blackmagicdesign.com/products/microconverters
www.blackmagicdesign.com/products/miniconverters

The SDI to audio de-embedder can produce either 4ch balanced analog audio or 4x 2ch balanced AES/EBU audio. SDI can carry up to 16 channels of audio at 24 bits (48 or 96 kHz, IIRC), and the de-embedder has switches to select which bank of 4 or 8 channels. You can daisy chain the SDI signal to a second unit if you want to use two to extract 8 balanced analog audio signals.

I'm not sure how good the DACs are so I splurged for two AJA ADA4 A/D D/A converters: these take 2x 2ch AES/EBU digital audio and convert to 4ch balanced analog audio, or vice versa, or half one way and half the other. These run a bit more: about $400 each, but they can sometimes be had for half that or less (I've paid as little as $95 used).

Woww.. Great find @rhollan ... We look forward to hearing how your project goes!

DevTeam

Here's a link to the AJA ADA4: www.aja.com/products/mini-converters/ada4

MSRP is US$390 but they can be had from anywhere from $95 to $195.

What bothers me is the lack of quality specs for the D/A converters in both the Blackmagic deembedder and AJA converter. As I have both, I'll be able to test: two daisy-chained Blackmagic deembedders would be cheaper and more convenient than one deembedder and two AJA converters.

Just received a nanoAVR HD. With my nanoAVR DL I can see tge effect of bass management before and after Dirac Live room correction. I expect no difference with level and delay adjusted speakers.

I will also have a chance to compare the AJA and Blackmagic DACs. Have to instalk four BG Radia PD6-LCRI speakers in the walls first.

rhollan wrote:

Richard wrote:

nowater57 wrote:

Genelec AD9002A . . . . . . . . . . . . £559.00
This is the only one in a price range for me, but I cannot find it by internet search. Can you help?

www.musicstore.de/en_GB/GBP/Genelec-AD92...r/art-REC0007204-000

Ah, 9200A! I was looking for 9002A...

nowater57 wrote:

I would love to get it direct from digital, if you have any suggestions how one de-embeds uncompressed 7.1 audio from consumer HDMI audio out of a bluray player or AV receiver, in a format suitable for a miniDSP Dirac product?

Unlikely to find cheap consumer hardware device that does this, as the market for such a device would be very small with typical consumers. The professional Avrus HDMI-2A will do it for a hefty price.
However, I was thinking more that you could play the Blu-Ray disc on a computer instead, and just route the 7.1 audio output paths to an external USB soundcard / audio interface which has whatever digital audio format connections you require, or maybe ADAT out to an external DAC solution.

Heh. I am doing exactly this. Better universal players (like the Oppo 10x and 20x series) have a secondary HDMI output, designed to carry audio.

What about devices without a second HDMI output? Could I still do the solution you mention below for audio, but take the SDI Loop output from the HDMI-to-SDI converter and feed it into a SDI-to-HDMI converter, then off to the video device?

Apparently, they will provide 7.1 LPCM audio over black video with no HDCP. (You configure the audio as either bitstream or LPCM, and, in the latter case, the Oppo decodes bitstream formats like TruHD, etc.) I suppose you could split off such a signal from an existing encrypted HDMI signal with something like an HDFury AVRKey. In any case, you can run that through an HDMI to SDI converter (SDI is a professional video format that carries uncompressed digital video over a single 75 ohm coax cable), and thence to an SDI audio de-embedder, Black Magic makes both kind of devices. Look up their mini and micro converters. Two boxes (under $100 for HDMI to SDI, and under $200 for SDI audio de-embedder) will give you 4x 2ch digital AES/EBU audio on balanced TRS connectors.

www.blackmagicdesign.com/products/microconverters
www.blackmagicdesign.com/products/miniconverters

The SDI to audio de-embedder can produce either 4ch balanced analog audio or 4x 2ch balanced AES/EBU audio. SDI can carry up to 16 channels of audio at 24 bits (48 or 96 kHz, IIRC), and the de-embedder has switches to select which bank of 4 or 8 channels. You can daisy chain the SDI signal to a second unit if you want to use two to extract 8 balanced analog audio signals.....

I must say this looks promising. Much appreciated. HDMI output from my source, into Blackmagic HDMI to SDI, then into Blackmagic SDI to Audio, which outputs 8 ch of AES/EBU for the DDRC-88D. US$300 for converters. If I need the video from the HDMI port, run the SDI Loop out into a Blackmagic SDI to HDMI converter. US$100 extra.

Does that look sensible to you?

Also, I'm not a huge video person, and don't understand everything I see on the Blackmagic website. Do I need the 6G or the 3G devices?

nowater57 wrote:

What about devices without a second HDMI output? Could I still do the solution you mention below for audio, but take the SDI Loop output from the HDMI-to-SDI converter and feed it into a SDI-to-HDMI converter, then off to the video device?

You will face two problems, though not insurmountable:

1) HDMI carrying "real" video (and not just black as a secondary "audio only" HDMI output would) will most likely have HDCP. You will have to strip it somehow, possibly with an HDFury AVRKey (which will give you "video" and "audio only" HDMI outputs). An advantage of the AVRKey is that it will pass full 4k video on the video HDMI output.

2) LPCM decoding. The minidsp and HDMI to SDI products expect LCPM audio over HDMI. They do not decode formats like Dolby TruHD, etc. Your playback device should be able to do this as an option. It is something to look out for. When a pre/pro or AVR does it, the data is sent over HDMI as a "bitstream". So, there should be a bitstream vs LPCM option. I'm not sure if the HDMI to SDI or minidsp units convey only accepting LPCM audio from the source so it could adjust "automagically". At least in the Oppo players, you can set it to bitstream, auto, or LPCM.

I must say this looks promising. Much appreciated. HDMI output from my source, into Blackmagic HDMI to SDI, then into Blackmagic SDI to Audio, which outputs 8 ch of AES/EBU for the DDRC-88D. US$300 for converters. If I need the video from the HDMI port, run the SDI Loop out into a Blackmagic SDI to HDMI converter. US$100 extra.

Does that look sensible to you?

Yes, though the video will probably be useless (black), unless you actually manage to strip HDCP from the video on HDMI. This is why all the fuss about "secondary audio only" HDMI outputs: they carry audio with black video without HDCP. Oh, and it's not US$100 extra: the Blackmagic HDMI to SDI micro converter is also a simultaneous SDI to HDMI converter, so yeah, you could loop the SDI video back. As I recall, however, if you provide an HDMI input and no SDI input, you will get the video on both the SDI and HDMI outputs (loopthrough).

Also, I'm not a huge video person, and don't understand everything I see on the Blackmagic website. Do I need the 6G or the 3G devices?

If you're just dealing with "secondary audio only" HDMI carrying 720p or 1080i black, the 3G devices are fine: they're good to 1080i. 6G is good to 1080p, and 12G for 4k. 12G gets expensive, and there are two ways to carry it: over four 3G cables, or a fibre cable. In my case I was interested in HDMI to SDI strictly from an audio perspective. because there were relatively cheap SDI digital audio deembedders.

Oh, and SDI can carry sixteen 24 bit 192 kHz audio channels, not just 8. And audio embedders are as available as deembedders, and they tend to have SDI loopthrough, just in case you need to run a bunch of audio somewhere.

I expect to be doing more testing along this route this weekend (or installing four surround speakers in my walls, or both).

I ended up going a different route: HDMI into nanoAVR HD into nanoAVR DL into HDMI to SDI converter and then to AES/EBU audio and through the ADA-4 DACs.

UNFORTUNATELY, the nanoAVRs seem to want to apply HDCP on their outputs EVEN IF the input signal is unencrypted (no HDCP negotiation). I am going to try an HDFury AVR Key to try and get around that. I was expecting the nanoAVRs to NOT apply HDCP on output if the input didn't request it.

We'll see if the AVR Key helps.

Oh, and SDI only supports 48 kHz audio sampling rate. I don't see that as a problem but some may,