If you want to convert your MIDI file to MP3 format without using specialized conversion software, you can do it using the free Audacity editor. Audacity is a powerful open-source audio recorder that manages to do much more than you think, despite being free software.
Steps
Step 1. Launch Audacity
If you don't have it yet you can download it from SourceForge.net
Step 2. Set inputs and outputs
Check your MIDI recorder or DAW is receiving the audio signal. The Audacity input should match the outputs of your MIDI recorder.
- You will find the outputs of your MIDI recorder in the audio preferences of that application.
- In Audacity, choose from the options in the drop-down menu next to the microphone icon.
Step 3. Select the output
Choose mono or stereo, whichever you prefer, from the drop-down menu next to the speaker icon.
Step 4. Check the levels
Set Audacity to "Record Ready" mode by pressing "Pause" (the two vertical blue lines), then "Record" (the red dot). Start the MIDI file, and in Audacity, set the input volume (the slider next to the microphone) so that the level meter rarely touches 0.
Step 5. Record your music
Once you are satisfied with the levels, bring your MIDI file back to the beginning, hit the "Record" button in Audacity, then hit the "Play" of your MIDI file. You should now see the waveforms of the audio signal in the Audacity track.
Step 6. Stop recording
When the song ends, press the yellow "Stop" button in Audacity, and then stop playing the MIDI file.
Step 7. Verify your file
Click on the "Play" arrow button in Audacity, and listen to your song to make sure everything sounds as intended according to your needs.
Step 8. Export your song
Select "Export…" from the "File" menu, name your file from the window that will appear and choose "MP3 Files" from the drop-down menu.
Note that you can also choose WAV, AIFF, WMA and many other formats - choose the one you think best suits your needs
Step 9. Enjoy your new file
Advice
- This method is certainly cheaper than buying professional MIDI conversion software.
- There are many other software of this type (besides Audacity) that offer this possibility, so if you already have one try it.
- If the midi file contains karaoke lyrics, the lyrics will be lost during conversion. If you want to keep the text even during the conversion and get mp3-karaoke files, a valid solution is given by KantoKaraoke, a software that converts midi / kar to mp3 while preserving the original text.
Warnings
- With large files, Audacity may take a long time to complete the export process, sometimes it may even seem to hang. Try to be patient.
- Make sure you don't do anything illegal with your new MP3.
