Converting from AC3

[Mr_Sheldrake]

Hi all,

I have a number of AC3 files I wish to convert to another format. When I play the original AC3 files in Windows Media Player they sound fine, so I guess this means the AC3Filter software (1.30b) is installed correctly.

When I convert the files from AC3 to any other format (WAV, AAC, etc.) the resulting sound file is garbled. The best way to describe the resulting converted file is it sounds like a 78 RPM record being played at 33.3 RPM (I know, I'm dating myself). In other words, it sounds like the playback is about 1/3 the speed. Dbpoweramp does not report any errors and the conversion "appears" to complete successfully.

I believe I have the DirectShow codec installed correctly. I have the .ac3 entry in the configuration file. I am running the latest versions of dbpoweramp (12.1), DirectShow codec, etc. I am using AC3Filter version 1.30b. Here is my configuration profile from dbpoweramp:

__________________________________________________ _____

Codecs Installed


Encoders (write)

Apple Lossless Release 6
.m4a
FLAC Release 7 (FLAC 1.1.4)
.flac
m4a Nero (AAC) Release 6
.m4a
mp3 (Lame) Lame 3.97
.mp3
Shorten Release 1 (Shorten Encoder v3.6.0)
.shn
Test Conversion
Wave Release 12.1
.wav
Windows Media Audio 10 Release 2 (WMA Pro 10)
.wma


Decoders (read)

Advanced Audio Compression Decoder
.aac
CD Decoder Release 12.1
.cda
DirectShow Decoder
.aa, .ac3
FLAC Decoder
.fla, .flac
m4a / mp4 Decoder
.m4a, .m4b, .mp4
mp3 Decoder Release 12.1
.m2a, .mp1, .mp2, .mp3, .mpa, .mpg, .mpga, .mpx
Shorten Compressed Audio File (*.SHN)
.SHN
Wave Decoder Release 12.1
.wav
Windows Media Audio Decoder
.asf, .wma, .wmv


Install on Demand

Monkeys Audio .ape
Musepack .mpc
Ogg Vorbis .ogg
Real Audio (Helix) .ra
WavPack .wv
Midi (read only) .mid

__________________________________________________


Again, the AC3 file plays just fine in WMP, dbpoweramp recognizes the AC3 file as a valid format for conversion, the conversion to WAV completes without incident but the resulting file is garbled. Any suggestions?

Thanks!

[Spoon]

What are the settings for the ac3? channels and frequency? and the settings for converted file?

[Mr_Sheldrake]

Wow, the man himself. Thanks for helping Spoon!

According to the right-click->properties page on the .AC3 file:

Channels: 2 (stereo)
Sample Rate: 48 KHz
Sample Size: 16 bit

When I do the conversion to WAV I leave dbpoweramp with all three of these settings configured to "as source". The right-click->properties of the resulting WAV file are:

Channels: 2 (stereo)
Sample Rate: 48 KHz
Sample Size: 16 bit
Bit Rate: 1,536 kbps

Encoder:
Encoder Settings: PCM
Audio Quality: DAT (Lossless)

I'm playing the WAV file in Sound Forge 8.0 so I know it's capable of handling a 48 KHz / 16 bit file.

The settings in AC3Filter are defaults across the board. I've even used the "Reset to Defaults" tool in AC3Filter - same results. If there is some way to capture the AC3Filter settings so that I could post them here (if that's important) please let me know. Otherwise I can go tab by tab through the settings and let you know what they're set to - again, if you think the AC3Filter settings are involved.

[Mr_Sheldrake]

Spoon, you were correct about the channels being the problem.

Unfortunately the right-click->properties screen was not giving me accurate information about the source AC3 files. I used GraphEdit and AC3Filter to confirm the source AC3 file was actually 5.1 channel, not 2 channel as the audio property screen indicated. I changed the output mode in AC3Filter to force 2-channel stereo output and now the WAV files are no longer garbled.

Thanks for your help Spoon. You are the man.

[Spoon]

It should work with 6 channel, try the new version here:

http://forum.dbpoweramp.com/showthread.php?p=64410#post64410

on 6 channels.