Film-Tech Forum ARCHIVE: Dolby DTS

This is topic Dolby DTS in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=16;t=002361

Posted by Burleigh Ibbott (Member # 3917) on 07-07-2015, 07:31 AM:

Hi everyone
We have a Dolby CP750 and we sometimes play Blu-ray disc's through it but notice that lots of blu-ray send out there sound in Dolby DTS. Our CP750 converts it to 2 channel only. Can this be adjusted in anyway to read in 5.1?
We do have a Kramer switcher too if this helps

Many thanks

Burleigh

Posted by Marco Giustini (Member # 4544) on 07-07-2015, 11:02 AM:

Nope. You'll need a BD player with 5.1 ANALOGUE outputs to feed the analogue multich INPUT of the 750.
Dolby don't want anything to do with DTS! [Smile]

There are also BD which convert DTS to DD on the fly, never tried them.

Posted by Manny Knowles (Member # 1171) on 07-07-2015, 11:40 AM:

Did I miss a bunch of memo's? What the heck is "Dolby DTS"?

Posted by Steve Kraus (Member # 476) on 07-07-2015, 12:32 PM:

It's not the 750 which is turning it into 2-track; it's the setting on the player. But down-converting to 2.0 is the correct setting for your situation since if you let it send out DTS (via fiber or coax) your 750 will do nothing with it and you'll have silence. (Always test the actual movie since menu sound may be in a different format than the feature).

If you are having the player dumb it down to 2.0 you can still tell your 750 to expand the 2.0 into multi-channel surround sound. Get into the 750 setup program and set that input to Pro Logic. Not as good as true 5.1 but much better than 2 channel stereo.

As Marco said, if you get a player with 5.1 or 7.1 outputs you can let it handle decoding of both DD and DTS (set the player to prioritize these outputs) and feed that into the 750's multi channel input. Then you won't even care which disks are DD and which are DTS.

Another option is an external decoder box. Fiber or coax in; multi channel output.

Hey Manny: Dolby DTS just like Deluxe Technicolor. Whoda thunk it?

Posted by Marco Giustini (Member # 4544) on 07-07-2015, 03:45 PM:

Dolby acquired DTS and SDDS some time ago.

Now we have Dolby Digital Dynamic Systems. DDDS. Doesn't sound too bad after all. Works in EX too.

Posted by Carsten Kurz (Member # 5396) on 07-07-2015, 04:38 PM:

Samsung Players (even cheaper ones) support DTS->AC3/DD conversion for DD bitstream output (also the other way round). The feature is called DD Re-Encode in audio setup, you can download a Samsung BD-Player manual and check it before you buy. It appears similar to 2ch ProLogic downmixing/encoding (which all DVD and BluRay Players support), but is not the same.

Aside from the more expensive Oppos, it is nearly impossible now to find players with discrete analog multichannel out.

- Carsten

Posted by Bobby Henderson (Member # 840) on 07-08-2015, 01:18 PM:

While having a DTS bitstream converted on the fly to DD might be better than nothing, I would be concerned about obvious drops in audio quality depending on what kind of DTS track the player is decoding and then re-encoding into DD.

It probably wouldn't be a harmful thing for a Blu-ray player to take a lossless DTS-HD Master Audio 5.1 bitstream, decode it internally and then re-encode it on the fly into lossy DD 5.1 for someone with a basic surround sound system.

If the player was taking an already lossy compressed DTS 5.1 audio track and re-encoding that into lossy DD 5.1 I'm certain audio quality would be adversely affected. It's two generations worth of lossy data compression.

For basic 2 channel playback that kind of thing is largely unnecessary. Any Blu-ray player can internally decode both DTS and DD audio formats. A growing number of HDTV sets are also equipped with DTS and DD decoding capability. Maybe this is why fewer new Blu-ray players are being sold with the analog outputs.

quote: Marco Giustini
Dolby acquired DTS and SDDS some time ago.

Posted by Marco Giustini (Member # 4544) on 07-08-2015, 01:55 PM:

I was joking Bobby, on the "Dolby DTS" thing! [Smile]