# Best sample rate conversion for 48 --> 88.2?

r8brain is a great program for sample rate convertion. It is free. Its big brother r8brain pro isn’t that expensive either. Both are highly rated.

Dean

The conversions can be done in whole numbers - it just takes 2 processes instead of one is all (details below).
How to approach depends on the projects & assets - if the whole project is at 48 and there are 88.2 assets to import, I would first back up project to a new folder, then swap sample rates & convert when asked - going up, we are padding existing files with zeroes so no harm, no foul. Incidentally we did this for fun last year after completing a 5.1 album mix supplied at 24/48. We created new copies of each project by backup to new folder, and then reset SR to 96KHz and allowed Nuendo to SRC up and simply re-ran the exports using exactly the same plugins, automation & mix - identical except we upsampled this one. We all heard a definite difference in the results very similar to the difference between 15IPS tape & 30IPS tape but not quite the same. The 48K versions had a slightly fatter & warmer low end whereas the 96K had better detail and superior imaging across the soundfield. This was unexpected - we thought we would hear a difference, but for it to be so pronounced was very interesting (although it must be said the mix was from stems (8 to 16 per track) that had been heavily processed (which is why we used them so as to keep the same sound as the stereo mix) before we got to them so we used very little in the way of effects apart from a few reverbs/delays and some sculpting/shaping EQ. But I digress…

As posted above, R8Brain is superb and it’s big brother is even better.
Both only use whole numbers to convert by means of the GCD (Greatest Common Denominator) as follows:
48000/300 = 160
88200/300 = 294
48000*294 = 14112000/160 = 88200
(The denominators always created by dividing the sample rates by 300. This gives you the factors needed for the conversion. Then take the first value & multiply by the second denominator and divide the result by the first one.
I think most of the decent SRC work this way these days but this websitehttp://src.infinitewave.ca/ is always revealing, I find - I wonder if the built-in SRC have got any better since v6/7 releases?)

Hope this helps

@ Neil - interesting post