[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.