Any tips for resyncing audio?

[Stuka]

I'm sure I'm not the only person that seems to have a bit of difficulty syncing audio files with shows that are available for ShowTime, LSX, etc. -
My recurring issue seems to be audio that starts out perfectly in sync with the show tracks, but starts lagging (generally) as the show progresses.

With this in mind -
Does anyone have any proven tips for correcting sync issues using Audacity or other audio editing programs?

Thanks!

[GoolGaul]

most audio proggies will let you adjust the time/pitch of a file.

if it's 4:05 just adjust it to 4:04 or :03

or u can turn the pitch up .01%

[masterpj]

tracks useually get an editted silence in the start, do check for this.
Check when the music starts, then in a video editor or audio editor make it so it starts at the exact same time the show starts
something like that

[allthatwhichis]

That shouldn't happen; what shows? I don't have that problem often... can't really remember the last time I did which I think turned out to be a music file issue, as in all I had to do was replace the file. I am not sure trying to "fix" the music is the best approach although I can't provide a better idea either except get a new music file.

[soforene]

Another possible solution may be the format of the music file.
i.e. MP3 vs WAV.

Might be worth converting (if your laser proggy accepts other audio formats).

[White-Light]

Depends on how it got out of sync. If you ripped it and the ripping utility slowed as it used up system resources, then you're pretty much screwed as the beat varies along the length of the track in a non linear way.

Best option in that scenario is find the location of the exact mix you need and buy it.

IF it just comes up short in a linear way, sometimes you can stretch the track.

[markmtts]

I always try and use WAV files for anything audio related from source (especially anything that needs sync to something else) and avoid MP3's. Even an audio track ripped to MP3 and then converted to WAV can have sync issues so in my experience it's best to rip direct from CD to WAV if possible even though the files are larger.

That said it can be difficult to get the exact audio track for laser shows even if you buy it online - it may have encoding issues which would may cause it not to align correctly. As others have mentioned the track may be cropped at the beginning differently also.

Having said that, I've also had success stretching the audio slightly by using a stretch audio function of audio editors to pull the beat back in line (time stretch rather than pitch), but as White-Light correctly indicates this will only work if the BPM is reasonably consistant otherwise different parts of the track will 'appear' to stretch at different rates.

[JohnYayas]

I don't know what media player is used with your application but I do know that some have problems with certain MP3/WMA formats. It could be a matter of simply encoding into a different format. Variable rate formats cause issues for sure.

[Stuka]

I don't know what media player is used with your application but I do know that some have problems with certain MP3/WMA formats. It could be a matter of simply encoding into a different format. Variable rate formats cause issues for sure.

Yeah, I think that is probably the root of most of the sync issues I have, at least when trying to use my MP3's that have been around for awhile -
I think I probably ripped most of them using a high, variable bit rate.

I'm probably going to have to dust off the CD footlocker and start ripping again!!
(At least for the tracks I want to sync to a laser show...)

[alexhu]

I recommand you to learn some music edit software such as audition,cooledit!
They're simple to learn,but useful for editing music.
Or else some syc software has the time offset function such as sunlite suite Easyshow.