44.1 kHz vs. 48 kHz - why not use the higher?

[Mr. Kelly]

Hey all,

I've been noticing on here that there are a bunch of people that say that their "standard" sessions are 24 bit 44.1 kHz. I've always used 24 bit 48 kHz sessions, then truncated down to 16 bit 44.1 kHz for mastering.

Anyone have reasons, other than file sizes, to NOT use a 48 kHz sample rate? Does the truncation yield a point of diminishing return, i.e., not produce enough of an improvement to offset the detriments of the truncation?

What session rates do you use?

[albee1952]

In theory, sample rate conversion may cause errors in the audio files. THis is the same logic that records at 88.2(instead of 96K) for a final product CD. The math to convert form 88.2K to 44.1K is simple, vs the math to convert from 96K to 44.1K. My philosophy is simple. If the end goal is audio(CD or uploads) I go 44.1K. If the end goal will be tied to video, I go 48k. In either case, I always record at 24 bit and dither the final 2mix during mastering (even if its nothing more than dither and Waves L2 for a rough CD. I bounce to disk at the original sample rate and bit depth. Any conversion or bit reduction gets done in a separate step in WaveLab(including mp3). Now, having said all this, if your ears tell you that 48K sounds better, then go with it(I have yet to have a client mention it).

[Top Jimmy]

Originally Posted by albee1952

The math to convert form 88.2K to 44.1K is simple, vs the math to convert from 96K to 44.1K.

So you had to go and whip out that chestnut huh albee? While it seems logical, it really doesn't matter.

But you are right. It's the SRC that has always been frowned upon. Avoiding it is looked upon as a step towards quality.

Historically, many SRC algorithms have been quite atrocious. While many have improved over time, you can see a visual of where some are currently here. http://src.infinitewave.ca/

And of course, Audioease's world-famous audio demonstrations. http://www.audioease.com/Pages/Barba...a4SRCTest.html

[albee1952]

I only stated my opinion No one needs to agree, and other views are always welcome(since I would not claim to be the end-all on this one). Besides......he started it

[waltz mastering]

Originally Posted by Mr. Kelly

I've always used 24 bit 48 kHz sessions, then truncated down to 16 bit 44.1 kHz for mastering.

Anyone have reasons, other than file sizes, to NOT use a 48 kHz sample rate? Does the truncation yield a point of diminishing return?

Truncating causes distortion.

[jazzdrumr]

Ask your mastering house what they prefer. The folks I use don't care what the file is, they play it out analog to their mastering system. Yes, it's a D/A and A/D conversion but they swear by it. Most of what gets distributed these days is MP3. CD's are so 1987! Why let 25 year old technology decide this? My 2 cents.

[daeron80]

For the most part, it's pretty hard to hear the difference between 44.1 and 48. They're just really close in frequency - about the same as one musical step.

Where it can show up a little more is when you do something that aliases, even only a tiny bit, and then apply distortion of some kind. E.g., poorly programmed soft synths that use some kind of generative function, like an FM synth built with SynthEdit. Or some guitar amp sims.

As you know, aliasing happens when a digital audio system is asked to represent a frequency greater than half the sample rate. Mostly, that's handled with brickwall filters at I/O. But they can sometimes be generated internally through a digital process. When that happens, it produces a new tone at Nyquist minus the difference. 48 has a Nyquist of 24, so if a frequency of 40 is required, a tone is produced at 8 (24-(40-24)). It's like a mirror reflecting those high frequencies back down. The big problem is, they're practically guaranteed to be inharmonic (read "ugly as heck"). Thankfully, they're usually too quiet to hear - UNLESS you apply harmonic distortion. Then suddenly it's harshness city. That's why it shows up with amp sims. They're all about harmonic distortion.

So, even though 44.1 and 48 aren't that far apart, using the higher rate does make it less likely that aliasing will occur, thus reducing the fizzy buzzies that plague many amp plugins.

Another reason to use 48, as albee said, is if it's sound for video or film. If it's going to be output at 48, it might as well start there.

Other than those considerations, I can't say I've noticed any difference.

[waltz mastering]

Originally Posted by Mr. Kelly

Does the truncation yield a point of diminishing return, i.e., not produce enough of an improvement to offset the detriments of the truncation?

I assume you sample rate convert, but instead of truncating why don't you dither when reducing word length?

Izotope has a very good src algorithm as well as dither program.

[necjamc]

I am learning something from this thread.

[chrisdee]

I'v not been able to hear any difference between 44, 48, 88 or 96 KHz, but I'm only on an mbox 2 pro.
Maby better AD/DA converters would make it more audible ?