Comment by vortico

The only issue with low bitrates is noise floor, so if you're hearing other distortions, it's not caused by the bitrate but maybe your room treatment or headphone drivers. A recording would have to have a hilariously large amount of headroom for 16-bit noise floor to be noticible when the music is played at a desired level, and while symphonic and jazz recordings have ridiculously high dynamic range, it's not 100dB of headroom, maybe 60, so 16-bit should be fine.

If you still think it's a problem, adding good dithering with ffmpeg's quantizer/resampler flags will make the noise floor 6-10dB smaller.