"In terms of quality for resampling, this is the canonical information source: http://src.infinitewave.ca/"

Yep, was looking at that. But would appreciate any additional insight, since I am not entirely sure how to read that. For instance, if I compare SoX to FFmpeg, yes, SoX looks way better in this particular case. Question is - are these meaningful differences?

Also, the test goes from 96kHz back to 44.1kHz, and people very rarely upload 96kHz.

So, I would mostly be interested in 48->44.1 and 44.1->44.1. Specifically, does anything change in the latter case?