This guide will show you how to convert your audio files to MP3 format with iMoviesoft MP3 Converter for Mac.
Steps:
step 1. Download and install iMoviesoft MP3 Converter for Mac

step 2. Add Videos.
There are two methods for you to add audio:

step 3. Select your aiming Profile and Output Folder for your audio
step 4. Adjust the Audio Parameters if you want.
step 5. Click “Start” button to begin the conversion.
Tips: You can pause, stop and continue smoothly when converting.
Two ways for trim

Audio Parameters
You can adjust different parameters of audio including Channel, Sample Rate, Channel, Audio Bitrate, Audio Codecs
Besides above edit functions, you can merge several audios into one output file.
Hopefully you can enjoy your videos on your iPhone with the help of iMoviesoft MP3 Converter for Mac
Related tutorial:
How to Convert Your Audio like MP3 to AAC, AAC to AC3, MIDI to WAV, etc on Mac?
How to Covert Your Audio like MP3 to AAC, WMA to AC3, MIDI to WAV, etc?