HDMI and digital out

[ackcheng]

I have done some readings and it appears the HDMI carries LPCM multichannels. If this is the case, we should be able to get the LPCM signal from universal players with SACD and DVD-A functions via HDMI interface.

anyone has any idea whether this may be feasible?

 

[Sangram]

You are correct, it does. I am now watching this thread.

I believe there is DRM involved in demuxing the HDMI signal into audio and video signals.

Keenly interested to see how it is implemented. There is some (somewhat unrelated, and somewhat preliminary) discussion at the Linux thread on decoding at least the audio signal, as it may offer an option to USB and SPDIF.

 

[voodooless]

If this is the case, we should be able to get the LPCM signal from universal players with SACD and DVD-A functions via HDMI interface.

Do we? I don't think so.... Why? Since HDMI can support MLP, when using DVD-A, it will siply directly stream MLP data via HDMI, and not convert it to LPCM first. SACD is kind of the same, if you hava HDMI 1.2, you will simply have a DSD stream via HDMI, and again: no LPCM. And in case you have an SACD player an no HDMI 1.2 of more, you have: nothing at all...

At least... that's what I think will happen.

 

[ackcheng]

I have come across some HDMI to DVI + SPDIF converters on the net. Google for HDMI SPDIF converter. But it doesn't say what is carried in the SPDIF? Not sure if it is only stereo or multichannel

http://www.converters.tv/products/digital_video_system_converters_431.html

 

[ezkcdude]

I was thinking about this the other day. There are some HDMI receiver chips available at digikey. I started to look through the data sheets - but it was way over my head. Something about TDMS, yada, yada. In theory, it is definitely possible. I played a CD through HDMI to an LCD tv recently. (That's what got me started thinking about it.)

 

[rfbrw]

You chaps ought to read up on HDCP.

 

[jheoaustin]

Setting aside HDCP that I don't know well, HDMI 1.0 ~ 1.3 can carry PCM, either stereo or multichannel. HDMI 1.1 ~ 1.3 Tx's are allowed to transmit multichannel PCM from DVD-A discs. HDMI 1.2 ~ 1.3 Tx's are allowed to output stereo/multichannel DSD. Unfortunately PCM converted from SACD contents are reportedly prohibited over HDMI link, but some Oppo player does that on HDMI 1.1.
Now HDMI 1.3 Tx's support all the mentioned formats over its link, in addition to that, they can transmit bitstreams of new audio formats for BD/HD-DVD like DD+, DTS-HD and TrueHD.

For clarification, multichannel PCM are transmitted over HDMI for DVD-A playback. For some reason, they didn't put MLP stream on HDMI, and it simplifies the system design by not putting MLP decoder on the A/V receivers and pre/pros.

If you can somehow get HDMI receiver chips or preferrably a boards (since HDMI chips would require some microcontroller intervention to work), getting PCM and DSD would be possible. It would be tricky to apply some processing on the DSD stream if needed, and decoding of new audio formats(even the old legacy formats) would be impossible at DIY level.

 

[rfbrw]

Setting aside HDCP that I don't know well,

In that case you are unlikely to get very far.

 

[jheoaustin]

In that case you are unlikely to get very far.

FYI, I am not going that way.

 

[jheoaustin]

Modify a receiver

If you guys want some HDMI receiver for multichannel digital audio, I'd rather go with modifying existing HDMI-equipped AVRs. They are cheap, and have all the input selection and even some decoding capabilities. Hacking the mute and I2S signals from DSP to DAC would be the thing to do. Then probably you can make or find multichannel S/PDIF Tx to get digital audio out of the box, and use multichannel S/PDIF Rx to receive the signals into your DSP or DAC boxes.

 

[ezkcdude]

You chaps ought to read up on HDCP.

I forgot about that. So, you would need to get a license to deal with the copy protection issues. That's a problem.

 

[KOON3876]

I heard Sony Playstation3 converts SACD to PCM inside and send PCM on HDMI, then TA-DR3200ES or upper can receive them.
does anyone has PS3? I wonder how about BD..


I already have DSD to PCM converter and SACD/DVD-A player, by http://www.dvdupgrade.ch, I hope they also hack BD or HD-DVD player

 

[jheoaustin]

I heard Sony Playstation3 converts SACD to PCM inside and send PCM on HDMI, then TA-DR3200ES or upper can receive them.
does anyone has PS3? I wonder how about BD..


I already have DSD to PCM converter and SACD/DVD-A player, by http://www.dvdupgrade.ch, I hope they also hack BD or HD-DVD player

I recently read about that news, but turned out that it only outputs downsampled/truncated stereo PCM or re-encode it to DTS over S/PDIF, not HDMI. Well, it still offers more options than before, but thinking that most SACDs are hybrid and thus have stereo PCM version of SACD contents, it is not a big deal, I am afraid.

 

[KOON3876]

I recently read about that news, but turned out that it only outputs downsampled/truncated stereo PCM or re-encode it to DTS over S/PDIF, not HDMI.

Hi I remember where I saw,
http://rec.mailarchive.ca/audio.pro/2007-02/1916.html

they say
"Linear PCM 7.1 Ch 192"
"The Sony STR-DA5200ES ($1200-1400) appears to be such a device"

hmmmm... expensive

 

[jheoaustin]

It appears that 7.1-ch LPCM means it's supported for some contents (probably DVD-A or BD/HD-DVD, or maybe even some crazy WAV), but not explicitly SACD. Unless one says explicitly that the SACD multichannel DSD contents were converted to multichannel PCM and then transmitted over HDMI, I wouldn't believe so.

I saw that menu with my PS3, and it appears to merely specify the PCM output over HDMI supported for any audio contents. It is not directly related to SACD. Moreover, '192kHz' makes it suspicious, as 88.2kHz or 176.4kHz is the right sample rate to convert DSD into. If DSD is converted to 192kHz PCM, it involves complicated and resource-consuming non-integer ratio sample rate conversion which also introduces some artifacts. So, I'd conclude that 192kHz PCM is not related to SACD.

 

[voodooless]

For clarification, multichannel PCM are transmitted over HDMI for DVD-A playback. For some reason, they didn't put MLP stream on HDMI, and it simplifies the system design by not putting MLP decoder on the A/V receivers and pre/pros.

Looks like you are right, but what would one extra decoder matter? In fact, HDMI simply goes for standards: anything SPDIF will do, multi PCM, and DSD (and the lossless DTS and DD standards as of 1.3). Anything else needs to be converted..

I heard Sony Playstation3 converts SACD to PCM inside and send PCM on HDMI, then TA-DR3200ES or upper can receive them.
does anyone has PS3? I wonder how about BD..

Here is all you need to know: http://www.ps3sacd.com/faq.html

It appears that 7.1-ch LPCM means it's supported for some contents (probably DVD-A or BD/HD-DVD, or maybe even some crazy WAV), but not explicitly SACD. Unless one says explicitly that the SACD multichannel DSD contents were converted to multichannel PCM and then transmitted over HDMI, I wouldn't believe so.

See FAQ above, apparently the PS3 converts multichannel SACD to multichannel PCM 176/24...

 

[jheoaustin]

Here is all you need to know: http://www.ps3sacd.com/faq.html

See FAQ above, apparently the PS3 converts multichannel SACD to multichannel PCM 176/24... [/B]

Thanks. There are some good information on PS3 and media formats. BTW, it doesn't clarify which HDMI version can receive 176.4kHz multichannel PCM. I know 1.3 can, but not 100% sure about 1.2, and for 1.1, I hear conflicting stories. Do you know if HDMI 1.1 can receive 192/176.4kHz multichannel PCM?

Surprised to see that SACD support is dropped from 3rd generation. The short and pale era of DVDA and SACD are phasing away.

 

[Cauhtemoc]

I saw that menu with my PS3, and it appears to merely specify the PCM output over HDMI supported for any audio contents. It is not directly related to SACD. Moreover, '192kHz' makes it suspicious, as 88.2kHz or 176.4kHz is the right sample rate to convert DSD into. If DSD is converted to 192kHz PCM, it involves complicated and resource-consuming non-integer ratio sample rate conversion which also introduces some artifacts. So, I'd conclude that 192kHz PCM is not related to SACD.

Although 192 kHz is not used, I doubt that the actual sample rate conversion would have been much problem for a PS3, this is exactly the kind of thing that the cell processor was designed for.

 

[tiefbassuebertr]

About the term "HDMI Audio Extractor" there are to find some devices

Who knows one of the follow "HDMI Audio Extractor" devices

1) Lindy
HDMI Audio Extractor | AV | Video / Monitor Extender, Splitter & Umschalter | Umschalter - Konverter - Extender | LINDY DE
http://www.lindy.de/lindyshop/manuals/38090V1.pdf
Impressum | LINDY DE
Grandbeing Technology Co., Ltd - Products - HDMI Audio Extractor

2) Luxi Electronics
Luxi Electronics
http://luxielectronics.com/Documents/Luxi AHD-110 user manual rev 0.50.pdf
http://luxielectronics.com/images/Luxi AHD-110 picture s.jpg

3) Octava Inc
1x1 HDMI Audio Converter. Extract audio from HDMI to Optical Toslink. Full 1080P resolution.

4) Altona
Atlona Technologies AT-HD570 HDMI Audio Extractor - Black Your Price: $151.79 - AValive.com - 1-866-93PRO-AV (937-7628)

5) CYP
CYP HDMI SPDIF, PCM 5.1 7.1 Audiodecoder HDMI 1.3c ATC zertifiziert | Scaler | Konverter | HDMI W

6) Various
Audio D/A A/D, A/D D/A converter, HDMI Audio extractor, analog/digital audio converter, Toslink switcher
HDCP HDMI to VGA + SPDIF RGB Component YPbPr Converter | HDMI to RCA Converter