Apply DRC or not when transcoding from AC3?

[nonoitall]

I'm transcoding some AC3 anime soundtracks, and am wondering, what's the 'standard' practice for dealing with DRC? Do people usually just transcode the unaltered soundtrack, or do they apply DRC to the audio as it's being transcoded? Is one way objectively better or 'truer' to the original than the other?

I've heard that unaltered audio is good for good sound equipment and DRC'd audio is good for weak equipment, which makes sense, but what's the best choice if you just want a happy medium? Is it easier to make DRC'd audio sound optimal on high-end equipment or to make unaltered audio sound optimal on low-end equipment? Obviously, I'm sure there are a lot of variables that come into play that could sway the case-specific decision one way or another, but are there any general guidelines I should follow when making the decision?

EDIT: Just to be clear, I am referring to AC3's custom varying DRC metadata which is obviously lost when transcoding to another format. I'm aware you can always apply more general DRC.

[tebasuna51]

Is it easier to make DRC'd audio sound optimal on high-end equipment or to make unaltered audio sound optimal on low-end equipment?

This is the only question than I can answer clearly:

Yout can't make DRC'd audio sound optimal on high-end equipment, it's more easy make unaltered audio sound optimal on low-end equipment.

Other questions requires more info:
For what you transcode AC3?
To what?
5.1 -> 2.0?

[AlexKane]

Optimal has to do with the amount of dynamic range you can handle. DRC itself, has multiple loudness profiles (Film light, Film Standard,...) spanning a variety of listening environments. Playback devices normally reproduce the intended quality of the source.

Downmixing to stereo without preserving DRC metadata, will most likely result in clipping though.

[nonoitall]

Yout can't make DRC'd audio sound optimal on high-end equipment, it's more easy make unaltered audio sound optimal on low-end equipment.
Thanks. Sounds like I'd lean toward not DRC-ing the audio in that case.


Other questions requires more info:
For what you transcode AC3?
To what?
5.1 -> 2.0?
I have two editions of the same show. One release has good video, but the other has more audio dubs. I'm matching up the latter's audio with the former's video, but there are certain points where I need to trim or pad the audio to sync them. For example, the opening credits on one are a few frames longer than on the other. So the audio stream does need to be altered a bit to fit the other edition's video. I suppose with some ingenuity and the right tools I could probably achieve what I want by losslessly cutting and joining but I think it would be more cumbersome, and less precise on the timing.

I may actually end up encoding to several different formats for different devices. Definitely AAC will be one though.

And it's a stereo source.

[tebasuna51]

Apply DRC can be recommended when downmix 5.1 -> 2.0 to avoid than low volume in center channel (dialogs) can be mixed with high volume in front channels.

Over stereo sources the mix is already done and apply DRC or not is less important.

[AlexKane]

Over stereo sources the mix is already done and apply DRC or not is less important.

Yes, sorry. I was referring to multi-channel sources.

[nonoitall]

Alrighty, thanks guys!