Why 16 or 24 Kbps and not 128?
To some, 16 Kbps is extremely low quality and would likely sound very dull and/or highly distorted. The trick is, don’t use Stereo sound, and use a lower sample rate than the usual 44,100 Hz. Why use Mono and 11,025 Hz? For one, there’s no real difference between mono and stereo from what I can tell, nothing significant. This cuts the file sizes in half. Also, I hate actual sound frequencies above 3 KHz and I always mute them on equalizers. 3KHz needs a sample rate of at least 6000 Hz. 8000 Hz sample rates on the MP3 player sound extremely messed up (even with 32Kbps bit rates) so 11,025 Hz is the next best. I also use a 4x offset so, for a 3 KHz sound, the minimum would actually be 12,000. 11,025 is a more common standard so I use it, even though 12,000 is one of the standards. You’d otherwise have to be near the speakers in a silent area to otherwise hear the very minute distortions, so minute they aren’t distracting at all. Also, for a 16-bit, mono, 11,025 Hz WAV file, the 128 Kbps
