Should LinguaLibre upload its pronunciations in FLAC format instead of uncompressed Wave files? FLAC compression is lossless, so it would save space (and bandwidth for users) without quality reduction. The only downside is that LinguaLibre’s server would use a bit more CPU for compressing the file. But that’s probably a very minor issue since it’s only needed once per file. To convert to FLAC in maximal compression, you can use something ffmpeg -i input.wav -compression_level 12 output.flac. Wikimedia Commons automatically transcodes FLAC to Vorbis and to MP3; see example FLAC file. Just a thought, not sure if it’s worth it.