DTS 768 to AC3 640?

[Xoemab]

Is it ok to convert DTS 768 to AC3 640? I heard that DTS 1536 is a bit better than AC3 640 and that DTS 768 is a bit better than AC3 448 so it seems not right to convert DTS 768 to AC3 640.

[microchip8]

if DTS at 768 kbps is "a bit better than" AC-3 at 448 kbps, then according to that explanation, AC-3 at 640 kbps should be better than DTS at 768 kbps. Remember that you're converting from one lossy format to another lossy format, so a "bit" of quality loss will occur. I don't think anyone can notice it, though

[tebasuna51]

Remember than there are other AC3's valid bitrate values between 448 and 640, if you think than 640 is to much and 448 to low, select 512 or 576 Kb/s.

[mindbomb]

unless you lack a dts decoder in your media player, I don't see the point.
and if this actually is the case, then you have no other options anyway... so there is not much to discuss lol.

Imo, 755kbps dts is pretty much equal to 640kbps ac3. However, that is assuming you are working with a lossless master and official encoders.

[tebasuna51]

Of course recode DTS to AC3 is for compatibility, there are many players/TV's without DTS support.

Recode a lossy format to another always lose quality, the question is how much you can assume.

@mindbomb
If you have the lossles master and good encoders, I think 640 Kb/s AC3 is much better than 755 Kb/s DTS, near 1509 Kb/s DTS.
This is a old discussion, each one can say your opinion but the discussion is closed.

[spawnbsd]

Of course recode DTS to AC3 is for compatibility, there are many players/TV's without DTS support.

Recode a lossy format to another always lose quality, the question is how much you can assume.

@mindbomb
If you have the lossles master and good encoders, I think 640 Kb/s AC3 is much better than 755 Kb/s DTS, near 1509 Kb/s DTS.
This is a old discussion, each one can say your opinion but the discussion is closed.
Agreed. Subjective testing done by many (including myself) show that AC3 @ 640kbit/s is subjectively +/- DTS @ 1.5mbit/s. Some people think it sounds better, some people think it sounds worse, either way it's extremely close in quality.

There was a good study done by EBU, that showed even AC3 @ 448kbit/s is virtually identical to DTS @ 1.5mbit/s.

My two cents.

[mindbomb]

im familiar with the EBU results, but I don't see it ruling out that 755kbps DTS would sound better than 448kbps AC3.
instead, i see it as 448kbps AC3, 640kbps AC3, 755 kbps DTS, and 1536k DTS all occupying a similiar plane of quality.

[filler56789]

IMHO, that study is outdated :devil: Now there exists the DTS-HD Master Audio Suite, now 755kbps and 1509kbps are not the only options available, and probably the DCA encoding algorithms have been improved a lot ;) since the days of the old CAE-4 hardware :D

[shon3i]

IMHO, that study is outdated :devil: Now there exists the DTS-HD Master Audio Suite, now 755kbps and 1509kbps are not the only options available, and probably the DCA encoding algorithms have been improved a lot ;) since the days of the old CAE-4 hardware :D
You partially right, since DTS specification is very simple, no room to improve something marginally, they probably improve something, but i doubt is spectacular, DTSMA encoder from mine earlier tests not give much better efficiency...