The internal recorder of the FP-30X can store one song.
The recording capacity is approximately 500KB per song, which is equivalent to playing "Für Elise" about 30 times.
Note:
- To record multiple songs, please save them to a USB flash drive (commercially available, 32GB or less). Songs are saved as MIDI files (SMF Format 0). Up to 100 songs can be stored on a USB flash drive.
See the "Saving the Recorded Song to a USB Flash Drive" section in the FP-30X Owner's Manual: https://www.roland.com/global/support/by_product/fp-30x/owners_manuals/ - The internal recorder saves performance data in MIDI format. To save your performance as audio, connect a computer to the USB Computer port (USB B type) and record using music production software (DAW).