Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
What is the diff between AC3 and AC3 Passthru? And why won't they work on ATV2?
- Thread starter marcel-v
- Start date
- Sort by reaction score
I assume you are talking about options in the latest handbrake nightly builds...
"AC3 Passthru" will take an existing AC3 soundtrack and include an exact copy as a track in the final encode.
"AC3" will take a non-AC3 source (ex. DTS for a DVD or Bluray) and convert it to AC3. This is useful for devices that do not support other formats (ex. AppleTV).
Both options will create audio tracks that are compatible with the AppleTV. There is likely something else about your encode causing your problem.
"AC3 Passthru" will take an existing AC3 soundtrack and include an exact copy as a track in the final encode.
"AC3" will take a non-AC3 source (ex. DTS for a DVD or Bluray) and convert it to AC3. This is useful for devices that do not support other formats (ex. AppleTV).
Both options will create audio tracks that are compatible with the AppleTV. There is likely something else about your encode causing your problem.
I am not sure how you mean that but i have 300 m4vs i encoded with handbrake with the 1st audio track selected being the AC3 track and the second audio track being the AAC track. Works fine in ATV2 as well as on iPad or iPhone
But are you getting 5.1 surround sound that way? It's supposed to be the other way around.
The ATV software looks for AC3 in track 2. If it's there, then it enables AC3 passthrough via the optical port. By default, track 1 is enabled and is AAC, AC3 is disabled and is track 2.
Attachments
On every file. I did not know that "it was supposed to be the other way around". What does that mean? Your saying the ATV2 cant play a AC3 track that is listed as track 2?
I have converted MKVs, Blu Rays (which go to MKV then to handbrake), DVDs and AVIs. My preset it the 5.1 track first followed by the AAC track. Whether its passthru or DTS conversion, I have never had a problem with one file.
The reason the Apple TV preset in Handbrake sets track 1 to AAC and track 2 to AC3 is because that's how the files from Apple are. Handbrake just replicate's Apple's videos for the Apple TV.
http://support.apple.com/kb/TA25199
http://support.apple.com/kb/TA25199
Those requirements on that support page are "should" and not "must" nor "shall."
Putting them in a different order doesn't violate the spec, and "should" work, but YMMV.
So if you set the dolby digital to audio, i believe if the AC3 track is track 1, it will not pick it up and instead play stereo. However, i am not sure why you would never set it to on instead of auto, which is how i have it, and this it works regardless of how it is encoded - track 1 or track 2. That said, no reason for me to not switch it from this point on in case something changes.
Hi.
What if the source is let's say "E-Ac3" and I select AC3 pass through, or DTS pass through, what is the output file?
Because it doesn't give any error as such if I select that.