Subject:Problem with synchronizing 2 long tracks

Posted by: sdavmor

Date:1/20/2002 11:16:38 AM

The Mellotronist in the Systems Theory project has just [this week] acquired ACID Pro 3.0. He has encountered a problem that I expect someone here can resolve. In his own words:
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I have got my hands on ACID Pro 3.0 and have been having no end of problems with it. I know that it says that it's designed as a loop-based recording facility, but you can use it as a multi-tracker if you want.

The major problem I am having is that if I (say) have an MP3 on track #1 and record an instrument 'live' onto track #2 I find that on playback, although #2 starts off properly, it inevitably loses synch with #1. If I play #2 back solo I can hear a bit of noise during which time some of the music is lost, seemingly having been chopped up.

The MP3 isn't beatmapped and obviously neither is the instrument on track #2. Any ideas?
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We've cleared up that the *guide* MP3 has noise glitches. He's using a Celereon 400 with 128MB of RAM, and the disk was defragged recently. I've suggested that he might want to set his project tempo to the same tempo of the MP3, and Beatmapping the MP3 might help. Also that adding another 128Mb of RAM probably would help the conversion of the MP3 in real-time. Wade in, folks.

Regards and thanks,
Steven Davies-Morris -- a 21st century schizoid man
http://systemstheory.net

Subject:RE: Problem with synchronizing 2 long tracks

Reply by: Maruuk

Date:1/20/2002 4:56:24 PM

Where to begin? SF openly states they "don't recommend" even a fast Celeron for Acid--not up to the task. Add to that SF doesn't support Acid with any CPU as a multi-track at all. Bottom-line, yes, the advertising is misleading. You don't want to use Acid to record whole tracks. Just little ones as loops or "one-shots". Oh yeah, while Acid will play back MP3's, the extra processing required to decompress the compressed audio further tasks the system. Fahgedaboudit! Get another app that can handle it all. They're cheap and good.

Subject:RE: Problem with synchronizing 2 long tracks

Reply by: Iacobus

Date:1/20/2002 9:17:06 PM

Try the following suggestions?

And what else is in the system? Soundcard? Programs running in the background? Version of ACID?

Iacobus

Subject:RE: Problem with synchronizing 2 long tracks

Reply by: sdavmor

Date:1/20/2002 10:11:57 PM

I'm sure that Mike tried to record his mellotron overdub while playing back an MP3 because I have no problem doing it on my machine [900mhz Pentium III with 1.5gb of RAM]. So he should convert the MP3 to WAV first -- we'd already concluded that -- and he should add another 128MB of RAM. Any practical pointers as to why the playback of the two files gets out of sync? They start fine, then drift.

Regards,
Steven Davies-Morrsi -- a 21st century schizoid man
http://systemstheory.net

Subject:RE: Problem with synchronizing 2 long tracks

Reply by: sdavmor

Date:1/20/2002 10:19:11 PM

Celeron 400 + 128MB RAM running Win98, Soundblaster card of some sort, no other programs running, defragged disc, ACID 3.0, not the latest build. Any thoughts as to why the two files drift out of sync during playback? Mike solved the immediate problem by re-recording out of his mixer into his minidisc unit, while playing the guide MP3 back through phones, then pulling the mellotron overdub onto the PC with Sound Forge 5.0, then importing it into ACID 3.0, at which point it synced perfectly. So what are we missing here?

Regards,
Steven Davies-Morris -- a 21st century schizoid man
http://systemstheory.net

Subject:RE: Problem with synchronizing 2 long tracks

Reply by: Maruuk

Date:1/21/2002 1:39:04 AM

My Celeron 600 was deemed by SF to be inadequate for all but the most basic procedures--the functional equivalent of a PII 400. If you must flog the dead horse, make sure the converted WAV file is played out of RAM by selecting a sufficiently long time in the "play one-shots of XX length as loops" options window. Loops = RAM playback. If none of that works, there are other inexpensive apps with full Acid support without these absurd limitations.

Subject:RE: Problem with synchronizing 2 long tracks

Reply by: Iacobus

Date:1/21/2002 11:37:49 AM

You can also double-click the respective track's track icon and, under the General tab, select "Loop" as the track type.

You'll get a warning on how much RAM will be used. Typically, a 3:00 minute song can take at least 45 MB of RAM or more, so be careful.

Also, note the approximate tempo of the loop and adjust the overall tempo of your project (or the loop itself) accordingly if you need to.

Iacobus

Subject:RE: Problem with synchronizing 2 long tracks

Reply by: SonicJG

Date:1/21/2002 12:03:20 PM

Hello Steven-

A standard Celeron 400 with 128MB of RAM and average drive performance should be able to handle what you're doing without problems.

When you bring the recorded file into Sound Forge and listen to it, does it have any audio drop outs(with snips)? If that's the case, that may explain why the sync is getting lost, and things don't work right out of the box. What kind of sound card are you using, and do you have the latest drivers for it?

Also, when the original recording happened, was the mp3 that was being used as reference set up as a beatmapped file or a one-shot? If that was a one-shot, and the file you recorded was a one-shot, they should line-up perfectly, minus the latency of your system set up.

Also, within the record dialog, was the "Make new track follow project tempo" checkbox checked? If yes, and both tracks are beatmapped, then you can check that both of them actually have the same tempo, by right-clicking on the track-type icon on the left side of the track view and noting the value in the context menu for "Use original tempo"--they should be the same, else you'll drift.

Another thing you can do with ACID to make them sync up is to use the Time markers("Hit" markers) originally designed for syncing your audio up to your audio up to a video clip, but can also be used to sync audio up to an audio one-shot. Drop a hit marker at the end of your one-shot recording by pressing H, then drop the cursor at the end of your beatmapped mp3, then right-click the hit marker's tab, and you can sync them up.

Hopefully this helps.

Sincerely,
Joel

Subject:RE: Problem with synchronizing 2 long tracks

Reply by: sdavmor

Date:1/21/2002 1:30:50 PM

Thanks Joel, making both tracks *one shots* worked like a charm. Much appreciated. I've suggested upgrading the soundcard to a 24bit beast and adding more RAM. The soundcard is actually okay, since the playback heads on an M400 are grungy and earthy [by the standard of modern digital sampling keyboards]. Some of the audio used to make the original mellotron and chamberlin tapes [like "3 violins", "mixed brass" and "solo flute"] weren't hi-fi recordings to begin with, so the 16bit card does a fine job. The Celeron will be upgraded to hold as much RAM as possible [384MB I believe], and my associate will make sure that he's configured properly in ACID before doing this kind of mellotron overdubbing in the future.

Regards,
Steven Davies-Morris -- a 21st century schizoid man
http://systemstheory.net

Subject:RE: Problem with synchronizing 2 long tracks

Reply by: sdavmor

Date:1/21/2002 1:32:37 PM

Thanks for the tips. Joel from SF solved it for us.

Regards,
Steven Davies-Morris -- a 21st century schizoi man
http://systemstheory.net

Subject:RE: Problem with synchronizing 2 long tracks

Reply by: sdavmor

Date:1/21/2002 1:33:22 PM

Thanks to you also for the tips. Joel from SF solved it for us with the *one shot* suggestion.

Regards,
Steven Davies-Morris -- a 21st century schizoi man
http://systemstheory.net