Best sample rate conversion for 48 --> 88.2?

Post general topics related to Nuendo 6 here.

Best sample rate conversion for 48 --> 88.2?

Postby Headlands » Mon Feb 24, 2014 3:56 am

Hey guys, I'm doing a project that's at 88.2k, and the vocals that were sent to me are 48k (both are 24 bit). What would you recommend as the best way to assure the best possible quality conversion? Use Nuendo to convert the actual files in the Pool? Or another way? I've done 88.2 -- 44.1 and vice-versa before, but am wondering if there are different considerations since 88.2 and 48 are not multiples of each other. Thanks!
Nuendo 6 and Cubase 7.5, Win 7 x64, 16GB RAM, UAD2-QUAD, Lynx Aurora 8, RME HDSPe, lots and lots of toys.
Headlands
Member
 
Posts: 524
Joined: Tue Mar 01, 2011 6:13 pm
Has thanked: 39 times
Been thanked: 28 times

Re: Best sample rate conversion for 48 --> 88.2?

Postby Rickard » Thu Feb 27, 2014 8:04 am

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
Win7|i7|12gig ram|LynxAES16|Lynx2C|Lynx Aurora|N6 + Nek|PT10 HD|UAD Quad x2| UM-3EX|Midex 8|Mackie Control + 2 extenders|too many mics and preamps to list
Rickard
Member
 
Posts: 218
Joined: Fri Jan 13, 2012 11:33 pm
Has thanked: 2 times
Been thanked: 6 times

Re: Best sample rate conversion for 48 --> 88.2?

Postby neilwilkes » Mon Mar 17, 2014 4:05 pm

Headlands wrote:Hey guys, I'm doing a project that's at 88.2k, and the vocals that were sent to me are 48k (both are 24 bit). What would you recommend as the best way to assure the best possible quality conversion? Use Nuendo to convert the actual files in the Pool? Or another way? I've done 88.2 -- 44.1 and vice-versa before, but am wondering if there are different considerations since 88.2 and 48 are not multiples of each other. Thanks!


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
www.opusproductions.com
Intel E5-2687W 8-core Xeon, 32Gb RAM, Windows 7 Pro x64, RME RayDAT, UAD-2 Octo x2 & Quad x2 (fully loaded), Adam A7 x5, WK ID Console
Nuendo 1-6, Cubase 6-7, WaveLab 5-7, DTS/DD encoders, Surround Edition etc, Waves Mercury
Blu-Ray authoring, DVD authoring & high resolution audio specialists.

Detailed Specs on request
neilwilkes
Senior Member
 
Posts: 1026
Joined: Thu Dec 16, 2010 11:55 am
Has thanked: 1 time
Been thanked: 10 times

Re: Best sample rate conversion for 48 --> 88.2?

Postby Robin Walsh » Mon Mar 17, 2014 5:53 pm

@ Neil - interesting post
Nuendo 6.5.2/64bit- Windows 8.1 -Nvidia K4000 - RME - UAD
User avatar
Robin Walsh
Junior Member
 
Posts: 149
Joined: Thu Nov 15, 2012 9:13 am
Has thanked: 10 times
Been thanked: 1 time


Return to General

Who is online

Users browsing this forum: No registered users and 3 guests