Connecting mutichannel sources such as PS3 to O1V96 via Toslink / ADAT

[mrg198]

Moderation: This query was originally appended to an old (Nov. '06) thread about multichannel input via a specific M-Audio sound card. However, since the requirement and solutions have diverged greatly, we've split this on off into it's own topic at the request of the OP.

 

 

I was getting horribly confused yesterday about ADAT/SPDIF/DTS etc.

 

I had thought that S/PDIF and TOSLink were synonymous. i.e. TOSLink was just an optical version of S/PDIF (as opposed to the RCA Coax version). Someone told me that S/PDIF supports only 2 channels and I couldn't correlate that to using a TOSLink cable to connect a DVD player or games console to a decoder and have 5.1 channels down the cable.

 

Correct me if I'm wrong, but I think I managed to tie this up on the basis that S/PDIF is about transmitting 2ch of audio as opposed to Dolby Digital/DTS etc. 5.1 channels of compressed data and the decoder turns it back into audio at the other end.

 

The reason I got into this in the first place is that I was wondering how I might connect a 5.1 ch source such as a DVD player to an O1V96 and if it was possible to avoid using the analogue inputs (I might want more than one connected) and somehow use a separate converter to convert to ADAT - thoughts?

[Shez]

I believe Toslink is the name of the connector. What signal you put through it is a completely seperate issue.

S/PDIF is a two channel signal; ADAT is an eight (or four at higher sample rates) signal. Dolby digital / DTS is a data stream that needs to go through a decoder before it can be used. All of the above can use toslink connectors; none will talk to each other.

[mrg198]

OK, so my next question - is it possible to get an HDMI to ADAT adaptor to convert 7.1 LPCM audio to 8 channels of ADAT? In fact, is LPCM audio in that form the same conding as used in ADAT?

[James]

For DTS on Toslink to discrete digital chanels try something like this

 

http://www.dts.com/pro-audio/cad5.php

 

Then an MY16 AE card in your 01v96 and you are sorted.

 

James

[mackerr]

The reason I got into this in the first place is that I was wondering how I might connect a 5.1 ch source such as a DVD player to an O1V96 and if it was possible to avoid using the analogue inputs (I might want more than one connected) and somehow use a separate converter to convert to ADAT - thoughts?

5.1 implies 6 channels of audio. While you can probably get the encoded 5.1 into the o1v96 via a stereo stream such as S/PDIF, to derive the 6 channels from 2 requires a decoder. Usually this is your home theater receiver. The o1v96 can mix in surround, but it has no decoder to get the 6 channels out of the encoded 2 channel signal that comes out of your Transit. You need a decoder before the console, and then you are going to need 6 inputs on the console.

 

Mac

[mrg198]

Apologies. I kinda hijacked the transit thread after a search for spdif and adat because it was describing a similar problem to mine - in my case how to hook a ps3 up to an O1V96 using ADAT.

 

The PS3 can output DTS, AC3, AAC or 2 ch LPCM (44.1 or 48kHz) over optical (TOSLink) but on HDMI will also do up to 7.1 LPCM @ 44.1kHz up to 192kHz. For any applications involving 5.1 and PS3 up till now we've used a home cinema amp and TOSLink to decode the 5.1 (either AC3 or DTS) or used DSP for videos playing from the hard disk to turn 2.1 into pseudo 5.1 and then use the pre-outs via 6 DI boxes to feed 6 amp and 6 sets of speakers. If we wanted to mix other sources such as radio mics into the system, then we took the L & R feeds into a stereo mixer input and added the mics and fed the mixer outs to the L & R amps.

 

I was looking at the O1V96 as a new addition to our kit and liked the fact that it would do 5.1 mixing. What I was trying to work out was if there was a neat way of connecting up PS3s to one of these without having to go through the analogue conversion and thus save all those analogue inputs. I could then hook up a couple of PS3s using an 2 x ADAT input card and still leave the analogue inputs for my radio mics etc.

 

Since I know a bit more about how all the digital audio encoding works for sending 6 ch over (and that S/PDIF isn't the same thing as) TOSLink, I realise you can't do away without the home cinema amp when working with encoded data streams such as DTS and AC-3, but what about using HDMI, which supports 8 channels of uncompressed audio? - in theory I think this means I could do 8ch into ADAT, but I'd need an HDMI to ADAT converter and I can't find one!

 

Secondly as a bit of an aside, I had to take the home cinema amp to a job to do this flying it with my luggage which was a pain since it is a) large and b) very heavy. I began wondering if I could save my baggage allowance flying 7 heavy power amps I didn't need by using some sort of decoder which didn't have power amps in but I couldn't find any! Does anyone know if such a thing exists? I'd need the complete range as for a home cinema amp - i.e. DTS, AC-3 and some DSP options as well but just gave line outputs (preferably balanced) in some sort of rack mount box and less than £600 if possible?

 

Thanks for the help so far though!

[mackerr]

One solution, all be it expensive, is the Dolby DP564 which has Toslink in and 4 sets of stereo AES outputs on BNC connetors, as well as analog out. To get the AES into the Yamaha console you need the MY8-AEB card which is 8 in and 8 out on BNC. There may be other pro surround decoders, but Dolby is the mothership.

 

Mac

[mrg198]

Interesting..although of course it only does Dolby based coding and not DTS (unlike the DTS one mentioned before which doesn't do Dolby). It seems there's nothing between a home cinema amp and the sort of thing you'd see in a cinema.

 

That still leaves the HDMI -> ADAT route as a possible conversion. The PS3 can do the decoding and output 8 channels of LPCM over HDMI so an HDMI -> ADAT converter would do the trick nicely. How can I get someone interested in making one of these?

[mshults99]

My motherboard, like many Intel Media Series motherboards, natively supports ADAT 8-channel, 24-bit x 48KHz LPCM audio out. I have an amplifier that natively accepts this format as input, D/A's it, and amplifies it into 7 speakers and a subwoofer. Nice solution.

 

However, it doesn't work under Vista, and I don't expect that it ever will, since HDMI is where everyone's energy seems to be focused these days. HDMI's fine, and I need it for video output, but I'd like to continue to be able to use my ADAT amplifier in the future.

 

Does anyone know of an external device that can take multichannel LPCM digital feeds over HDMI and convert them to ADAT? This could require down-sampling, since ADAT can only handle 24x48 into 8 channels (and my amplifier can only handle 24x48, regardless of the number of channels).

 

My alternative is to replace the ADAT amplifier with an HDMI amplifier, but I'd rather not do that.

 

The ADAT amplifier is from Simplifi Digital (www.simplifidigital.com). It's inexpensive, and very high-quality.

[mervaka]

My motherboard, like many Intel Media Series motherboards, natively supports ADAT 8-channel, 24-bit x 48KHz LPCM audio out. I have an amplifier that natively accepts this format as input, D/A's it, and amplifies it into 7 speakers and a subwoofer. Nice solution.

 

However, it doesn't work under Vista, and I don't expect that it ever will, since HDMI is where everyone's energy seems to be focused these days. HDMI's fine, and I need it for video output, but I'd like to continue to be able to use my ADAT amplifier in the future.

 

Does anyone know of an external device that can take multichannel LPCM digital feeds over HDMI and convert them to ADAT? This could require down-sampling, since ADAT can only handle 24x48 into 8 channels (and my amplifier can only handle 24x48, regardless of the number of channels).

 

My alternative is to replace the ADAT amplifier with an HDMI amplifier, but I'd rather not do that.

 

The ADAT amplifier is from Simplifi Digital (www.simplifidigital.com). It's inexpensive, and very high-quality.

have you considered reverting back to XP? vista is turning out to be a horror story for a lot of people, especially over here.