Upsamling audio from 22.5k to 44.1k?

[Bahamuth]

Hey everyone,

I have several audio files with bitrates like 22.5k and I think down to 8k sometimes. (MP3/WAV files) Most are Stereo, some are Mono.

I can easily keep the original files and play them on my PC.

But let's say I want to unify everything to 44.1k Stereo files, like for players who don't support this low settings. What would be the most quality way these days to do that? Many years ago I have heard SSRC was the best way to do such.

But how is it today? Any suggestions? I'll keep the choice of output file type open to hear as many suggestions as I can.

[Brazil2]

Many years ago I have heard SSRC was the best way to do such.

That or r8brain or SoX:
https://sourceforge.net/projects/sox/

Resamplers comparisons:
https://src.infinitewave.ca

[j7n]

Compare the 8K by ear. I would relax the settings in SOX to leave some aliasing. The "best" software aims to create a rectangular response, which sounds unnatural where you can hear it.

[Bahamuth]

Thank you for your suggestions! I will try them out and will believe my ear what sounds best.