export with 0db gain, +3 db gain, +6 +9 +12 db gain.
The mobile phone has only one speaker for ringtone, so mono.
Additionally I can assume the speaker is not the best, so the equalizer.
Sometimes the music is faint so I add a gain. Then I choose the gain which sounds best.
Could you tell me something about these steps?
Anything I could do better?
Just note that gain is relative, so a gain of +3dB or +6dB doesn’t tell you “where you’re at.” It’s the change you’ve made. So, I think it’s fine if you make 3 or 4 versions with different loudness and then choose the one you like.
Most commercial releases are “normalized” for 0dBFS peaks, and if you go over 0dB you can get clipping (distortion). But, some distortion should be OK for a ringtone if you’re not otherwise getting loud enough.
The peaks limit how “loud” you can go without clipping, but peaks don’t correlate well with loudness. That means you can have a normalized/maximized track that doesn’t sound very loud.
NOTE - Normally, you should avoid editing MP3 (if possible) because MP3 is lossy compression. It gets decompressed when you open it in an audio editor, and if you re-save (export) to MP3, you age going througn a 2nd lossy compression step.
The quality loss isn’t always noticeable and for a ringtone it probably doesn’t matter.
There are special purpose MP3 editors that can edit without de-compressing/re-compressing, but certain things like EQ can’t be done without de-compressing first.