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Steve MacMillan 11-28-2007 09:07 AM

Rhythmic algorithm
 
You might find this interesting...

It is my understanding that the Rhythmic algorithm works by not stretching the first bit just after the warp marker, then after x number of ms. the audio starts stretching. This is designed to preserve the transient.

OK, I just did a test with five second cymbal crash sample. I put the cymbal on the top of bar two and consolidated back to bar one. I duplicated the track, and phase flopped the dup. I put the dup into Rhythmic mode and manually put an Analysis marker right at the top of the cymbal. Then I warped the cymbal so that it started at the same place but extended out to 7 seconds.

Play both and there is total cancellation for 1 second. Then you can hear the stretch work. This is a really great algorithm. The cymbal transient cancelled completely. You should not experience any smearing of the transients.

In my experience of correcting a couple of drum kits, there were a few spots (mainly very open crashes and hi hat scoops) where I could hear the transition from transient to stretch. This was a 250ms kind of flangy moment. I found that by manually moving the warp marker's placement to the left and then pulling the warp maker left until the audio lined up on the grid. I was able to shift the transition to a better place.

STeve

Steve MacMillan 11-28-2007 10:26 AM

Re: Rhythmic algorithm
 
One more thing. Should you decide to render with the X-Form plug-in, it no longer cancels at the transient. But the standard render does. So maybe the standard render is more suitable for rendering drums.

STeve

SessionKat 11-28-2007 10:44 AM

Re: Rhythmic algorithm
 
Quote:

You might find this interesting...

It is my understanding that the Rhythmic algorithm works by not stretching the first bit just after the warp marker, then after x number of ms. the audio starts stretching. This is designed to preserve the transient.

OK, I just did a test with five second cymbal crash sample. I put the cymbal on the top of bar two and consolidated back to bar one. I duplicated the track, and phase flopped the dup. I put the dup into Rhythmic mode and manually put an Analysis marker right at the top of the cymbal. Then I warped the cymbal so that it started at the same place but extended out to 7 seconds.

Play both and there is total cancellation for 1 second. Then you can hear the stretch work. This is a really great algorithm. The cymbal transient cancelled completely. You should not experience any smearing of the transients.

In my experience of correcting a couple of drum kits, there were a few spots (mainly very open crashes and hi hat scoops) where I could hear the transition from transient to stretch. This was a 250ms kind of flangy moment. I found that by manually moving the warp marker's placement to the left and then pulling the warp maker left until the audio lined up on the grid. I was able to shift the transition to a better place.

STeve

thanks for the 'applause' here Steve. The Rhythmic algo is a cousing on what is used in Synchronic, and uses a bit of the "Fill & Smooth" from Beat Detective.

To preserve a smooth tail of a stretched trasnients' decay, Rhythmic uses a micro-sized forward & back loop iteration of the tail, with tiny micro-fades apllied to increase smoothing. You will find there are some physical limitations of this when applying extremely long stretches, but we also offer the Decay control to adjust characteristics.

Finally, consider all these algorhythms as "Version 1" with many years of improvements to come!

Cheers,

-tv

PaulV 11-28-2007 10:44 AM

Re: Rhythmic algorithm
 

Yes, good point. For rendering drums, Rhythmic will often do a better job than XForm.


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