resample quality - OUCH !!!

wazer wrote on 5/3/2003, 9:35 AM
uhh.

I'm working on a MIXcd for my DJ friend. I have to adjust the pitch (like on the turnable) many times in one song, becouse the turntable doesn't play static tempo. (sorry, i don't know the right word for it). Sometimes i need to adjust at least 30-40 cents to get the tempos matched at the mixes.

It's so simple to do this in the VEGAS. That's why i love it.


THE PROBLEM IS : T H E S O U N D !!!!

JesusChrist!
I'm using VEGAS for a long time, but i didn't expected this until now.
(..where was my ears?..)

When i change pitch - NOT the PITCHSHIFTER algo! - in VEGAS it LOOSES the HIGH frequencies! (at resample quality : Best.)

I tried to do this via OPEN COPY - of the original file - in SoundForge.
That's OK! (at accuracy 3 - High )
It means a lot more time on editing... And that is so boring..
(Adjusting the take w/CTR, then looking for the pitch value in the take's properties (memorize it), then set back the algo to NONE, then open copy in SF, then apply pitch shift, then save and return to VEGAS.... )

Now if i count after i won't be finished the CD till deadline. If i wanna make it right.

And now i know why my DIGITAL mixes in VEGAS sounds so "dummy".. I've used this method a lot..

Anybody?

w!

Comments

bgc wrote on 5/3/2003, 3:59 PM
Doing good resampling is very expensive computationally and Vegas has to do it in real-time so it's not going to be the best algorithm. While Sound Forge is boring, it's really the best way to do it. Sorry.
Sari wrote on 5/3/2003, 8:41 PM
Find and get Prosoniq's Time Factory. The best program that does only two things: Pitch Change and/or Time Stretch. It is very good.
PipelineAudio wrote on 5/3/2003, 10:17 PM
could be the same anti-aliasing (or sometimes even aliasing ) plauging the whole plugin market with wet blanket over the audio sound effects
Geoff_Wood wrote on 5/3/2003, 11:53 PM
If I was trying to do what wazer is, I would be using Acid, not Vegas.
stakeoutstudios wrote on 5/4/2003, 5:36 AM
there should be an extra option to increase the quality of the algorithm used at the expense of CPU though. That would be especially nice!
wazer wrote on 5/5/2003, 5:57 AM
Webpuppy's right.

Or when i adjust the pitch, the VEGAS sholud ask for "make a new take?" and P-R-O-C-E-S-S IT, exactly like SF does. I have 1-2 secs to wait, but i don't have BETTER idea/program to work with...

Easy of use AND the quality are the keywords to me..

w!
SonyMLogan wrote on 5/5/2003, 1:57 PM
Wazer,

There is indeed a bug in Vegas 4.0's "Change length and pitch" stretching process. Filtering is being applied with inappropriate cutoffs in several instances. This results in loss of high frequency signal dependant on output frequency.

One method to get around this problem is to render your output to a project rate higher than your desired output rate, then resample the file to your desired output. For example, say you need to produce a product with a sample rate of 48k. First render your project to 192k (using "Best" resample, then resample the rendered file to 48kHz.) There is only a 4dB roll-off (versus a 90dB roll-off if your output is initially 48kHz) at 24kHz.

As to the suggestion that CPU utilization prevents the current "best" algorithm from being as good as it could be – this is not the problem. Vegas is already designed to provide a range of resampling methods ranging from "fast-n-crude", to "slow-and-pristine". Check out your relative CPU usage between “preview” and "Best" if you don’t believe me.
bgc wrote on 5/5/2003, 2:57 PM
Hi Matt,
Thanks for the feedback/update. Looks like my information was old or incorrect.
bgc
GaryStebbins wrote on 5/6/2003, 2:34 PM
Matt, will this bug be fixed in 4.0c?