

For lower bitrates, I’d suggest using a different codec than MP3. Opus is really solid, and at 128 kbps it will probably get you quality similar to MP3 at 192 kbps. Or you could go lower, and 96 kbps with Opus will be similar to MP3 at 128 kbps. I don’t know an app that will do it automatically, but the CLI tools are really simple to use: you point them at the FLAC and tell it the target bitrate and that’s it.
Alternatively, if you have access to a macOS machine, their AAC encoder is really good and likely superior to any MP3 encoder at equivalent bitrates.
Hey! Good to know about the 128 kbps threshold.
What’s your take on MP3 bitrates? I’ve read some posts online claiming that 320 kbps is overkill most of, if not all of, the time. They claimed that there is little to no gain going above around 220 kbps. In your experience, is there any truth to this?