sincere compliments for the excellent series of tutorials, well-made and exhaustive.
I have connected an old but working audio interface to my Mac, an Edirol UA25, and a keyboard, also vintage, a Korg M1, which I use as a silent keyboard (and which works very well).
The sounds available in the software library are excellent, but the program would still allow for the use of external ones, as is the case with those from the M1.
I have resolved many problems of various kinds, thanks also to the tutorial, but I haven't found a way to use sounds from external MIDI instruments, neither here nor elsewhere.
I have some keyboards that are now quite old and I would like to integrate these banks into Logic; my attempts so far have failed.
There is no way, as far as I know (it's not even written in the Logic manual), to import external sound banks into Logic. It is possible to use them with external MIDI, by connecting an external MIDI device and making it play using MIDI regions in the external MIDI track. It is then possible to recover the audio signal coming out of the external MIDI instrument and send it back to Logic in an Audio track, this time in waveform form. As has also been stated in the video courses... MIDI Track -> Uses MIDI IN (MIDI input from external peripherals), Audio Track -> Audio input from external peripherals or microphones, External MIDI Track -> Uses MIDI OUT towards external MIDI peripherals. In reality, the process described above is equivalent to performing a bounce in place (realtime) of what is heard, utilizing MIDI data outputting to an external MIDI instrument that plays by sending the audio stream to the LINE IN of a sound card.
An alternative could be to sample the sounds of the instruments using Logic's EXS24 sampler and then reuse them when needed.
This topic has already been discussed in the forum at this link
External sound banks are proprietary to the system on which they are used. One would need to look for players and/or emulators if they exist for that particular system.