Good evening,

I occasionally edit PAL dubbing (25p / 50p / 50i), which I then have to adjust to match the image of the original (usually 23.976 p or 24p). The way I prefer to do this is to do the conversion in the first step with an Sample Rate Converter (SRC) according to the formula: source framerate : target framerate x 48000. I use the SRC from iZotope RX9 Advanced. I noticed that the audio track after the conversion does not hit the exact length of the original. Often I have to use crooked values to get closer to the length of the original. A few years ago I did such frame rate conversions using the Pro Tools algorithm. This never resulted in such differences in length. Unfortunately, I don't currently have access to Pro Tools. Also, PT's built-in SRC is not one of the best.

Does anyone know of any alternatives and can make a recommendation? I have other SRC, but they all work with fixed sample rates and don't allow crooked input like 46080. It is often only a matter of a few frames, but in some cases this leads to a visible deviation in synchronicity between picture and sound. At present I help myself by setting several intermediate cuts in order to correct once again within the audio track. However, this is comparatively time-consuming and therefore I would like to spare myself this.

I thank you in advance for your helpful answers.

 

Voxengo - r8brain is a free audio sample rate converter application.
www.voxengo.com/product/r8brain/

 

Did you try yor editor of choice, like premiere does it well enoug

 

Thank you for your answers. (Unfortunately I didn't see them earlier or I would have replied sooner).

I currently only work with audio (Sequoia) and don't have access to Premiere or Avid at the home office. (I could possibly test Resolve. But I am not familiar with this program.)

I even own the "Pro" version of this program. But unfortunately with "r8brain" you can only set fixed values (e.g. 44.1 / 48 / 96 kHz). But I need the possibility to enter free selectable values (e.g. 50050 kHz).

 

Convert audio online
www.aconvert.com/audio/

 

Last edited: Mar 15, 2022

This seems a tricky problem indeed. As you said a fraction doesn't give enough accuracy the moment the video lasts a while.
Perhaps would be easier to dub (record) at the closest standard freq (44.1/48/96) and then to use a time-stretch program/plugin to match the exact duration.
A shot in the dark but off the top of my head...