Subject:tempo change

Posted by: CharlesGarrett

Date:10/31/2003 2:32:37 PM

Unique problem: I need to effect a gradual tempo chage over several seconds (specifically, increase speed by 4% over roughly 3 seconds) in a recorded wave file. (i.e. accelerando) I don't know of any way to do this in SF, Acid, or Vegas. I have another program called Millenium Live, which will make tempo changes over time, but pitch gets altered as well, which is unacceptable in this case. Any ideas or techniques to get this effect?

Subject:RE: tempo change

Reply by: Rednroll

Date:10/31/2003 3:09:56 PM

You can do this in Sound Forge.

Select the part you want to change the Tempo.

Goto EFFECTS>PITCH>BEND. This will bring up the selected area with a pitch bend envelope, where you can add points and do exactly what you're looking for.

Red

Subject:RE: tempo change

Reply by: JTelles

Date:11/1/2003 7:56:56 AM

Another possibility is downloading the demo of Waves Transform bundle. It comes with a sound shifter plug-in that does tempo/pitch changes. The plug-in takes a lot of cpu power but the results are the best I have experienced. so far...
JT

Subject:RE: tempo change

Reply by: CharlesGarrett

Date:11/4/2003 8:14:39 PM

I need to change tempo OVER TIME. (i.e. faster and faster over several seconds)There can be NO pitch change associated with the tempo change. The recomended pitch/bend/shift idea changes the pitch, not the tempo. The tempo/stretch function changes tempo immediately, not over time - i.e. accelerando. Evidently no way to do this in the SF family. It would be a nice addition though. hint hint.

Subject:RE: tempo change

Reply by: CharlesGarrett

Date:11/7/2003 11:21:53 AM

OK, I've checked out the waves bundle, but it doesn't include "sound shifter" which is the plug-in which will change tempo over time (accelerando) without changing pitch. The Waves stuff or the serato "pitch in time" stuff would involve mega-bucks (including ProTools or bundled plug-ins) just to get a tempo-over-time plug-in. Is there any other option? Why is such a plug-in so costly?

Subject:RE: tempo change

Reply by: Rednroll

Date:11/7/2003 3:10:12 PM

You could effectively do this in Vegas or Acid if you have either of those programs. In Acid you could drop consecutive tempo markers and slow down the tempo without changing the pitch. In Vegas you could cut the part up into different events, and changing each events duration to something longer and make sure you have "Change Time, not Pitch" selected for each event.

Subject:RE: tempo change

Reply by: JTelles

Date:11/7/2003 4:33:36 PM

"OK, I've checked out the waves bundle, but it doesn't include "sound shifter" which is the plug-in which will change tempo over time (accelerando)"

As I mentioned in my previous post, you find it in the new TRANSFORM BUNDLE. Check the site below:

http://www.waves.com/htmls/prods/transform/soundshifter.html

The Sound Shifter Graphic allows you to draw a time envelope over a waveform screen, hence you can accelerate as you wish, WITHOUT changing the pitch. I suggest you download the demo (it's FULLY operational but expires in 2 weeks or so) of the Transform Bundle. As for the price, yes Waves plug-ins are always expensive, but at least you have the demo period long enough to play with it for free.
Good luck
JT

Subject:RE: tempo change

Reply by: CharlesGarrett

Date:11/7/2003 4:46:43 PM

Thanks guys. I do have SF, Vegas, and Acid. I found an earlier thread suggesting to chop the file into pieces, but as I recall, the person who tried it found the resulting product unsatisfactory. When I downloaded the waves bundle, it did not have the pitch shift plug-in. The stuff I did get looked very interesting. Perhaps worth purchasing.

Subject:RE: tempo change

Reply by: CharlesGarrett

Date:11/13/2003 12:12:31 AM

You are right and I was wrong. I had looked at the wrong download. I tried it and I liked it. Though it is expensive, I'm considering buying it. I do a lot of editing of pre-recorded material, and this program sounds great. I need to upgrade my SF to take full advantage of this program since it appears I can only affect one minute of audio with SF 5.0. (the site says you must use SF 6.0 ((or better?)) to use the plug-in) so I guess I'll be upgrading soon. Thanks for the help.

Subject:RE: tempo change

Reply by: JTelles

Date:11/13/2003 4:56:13 PM

Glad I could help...
Just one more thing:
Pay attentiom to the "TOTAL TIME -> INPUT TIME" in the screen of the Sound Shifter. I notice it defaults to 1 minute (it happens in Sound Forge 7 as well) and NOT to the total time of the Song you are processing. YOU HAVE TO TYPE the real total time of the wav file you are processing, otherwise it works for 1 min only and may crash or simply interrupt the processed file. Are you sure that is not what is happening to your tests? It took me a while to figure this too and you have to type the input time, sometimes more than once, to be sure it registered the actual time of your file. Once it gets this, the processing is never interrupted and the results are very good...
Another thing is , you need a fast computer to be able to preview (PIV 2.4GHz I know is ok, but PIII 1GHz can stutter in preview), but offline it works alright in a PIII 500MHz.
JT