PureBasic Forums - English

For testing purposes I would like to mix a few audio clips down to 5.1. Actually, I would like to create a short sound track which contains of a few test tones plus two music samples. After that I'd like to play that soundtrack over a specific channel, ie. Left front and nothing else, right front and nothing else, etcetera.

I've been looking around, and though Audacity is supposed to be able to do it, I can't figure out where that function is hidden but anything else (which is free, obviously ) could be the ticket.

Any suggestions?

Well, got one step further. Managed to create a .WAV and .AC3 file with 5.1 contents, but haven't been able to play it back on my home cinema kit...

If I play it on a laptop, which is connected with SPDIF to my amplifier, no DTS or DD is ever decoded. I have some other .WAV files that I found on the internet, which are recognized by my amplifier when I burn them to CD and then play them back, however they are not recognized as DTS or DD when I play them from the laptop over SPDIF.

The other problem (alternative solution) is the .AC3 / .WAV files I've created myself are not swallowed by Nero, so how to get them on a CD?

Suggestions welcome...

a) 5.1 WAV and 5.1 AC3 di have different channel orders, so watch out

b) If you do simply burn a WAV PCM Stream to CD and feed it to your DS Amplifier this probably wont be recognised as DolbyDigital and for shure not as DTS (DTS is a compression algo just like AC3). Such a WAV will be recognised as uncompressed PCM Bitstream (some DVDs do contain PCM Tracks)

So do crete a 5.1 wav file in for example Audacity (If Audacity really can handle 5.1) or do chose a diff. software like the Audition from adobe if it can handle 5.1.
When you got a correct channel ordered 5.1 WAV you can use ffmpeg or aften to create a DD compilant AC3 stream which will be recognised by your DolbyDigital Setup.

Well, I got one step further... or actually a few steps, but ran into some interesting things...

Problem 1 - 5.1 mix in Adacity - solved, it works, I can export 5.1 AC3 files
Problem 2 - 5.1 over SPDIF from my laptop to my amp - can't get it to work, dunno why
Problem 3 - Nero AC3 plugin - solved, I can burn AC3's to audio CD's
Problem 4 - I don't understand how audio files are recognized
Problem 5 - well, more of a question - what does the surround led on my amp make light up?

Here's the thing: you can find some files on the internet in .WAV format, containing DD or DTS information. Try, for example, the sample files on Kelly Industries, or those on masterpinguin.de

Now it gets interesting: currently nothing played on my laptop over SPDIF is recognized by my amp as surround, this may be caused by the laptop though... But... there is some inconsistent behaviour when playing back files from a CD. Here's what happens when I burn the downloaded .WAV or created .AC3 files on CD and play it back on my kit:

kelly industries wav file (DD) -> audio track on CD -> digitaal to amp -> works and is recognized
kelly industries wav file (DD) -> audio track on CD -> analoog to amp -> doesn't work
own creation ac3 file (5.1) -> audio track on CD -> digitaal to amp -> works but isn't automatically recognized
own creation ac3 file (5.1) -> audio track on CD -> analoog to amp -> works but isn't automatically recognized

To play back my own AC3 in surround mode I have to change the setting of my amp to 'ProLogic', 'II', 'Neo', 'Multi' or whatever, but it won't recognize my own tracks in 'AFD Auto' mode. Appearently there is a difference

Audacity is really a daft program. Use reaper instead, it does everything what you can do
like the pro's out there. Only reaper comes with a clear interface and without the bloatware,
it's only 5 Mb. It comes with a fully working trial and it will continue working even after
the trial, leaving it up to you. Download : http://www.reaper.fm/
cw