I just picked up a Roland D-5 and a D-20 synthesizer but I want to reset them to their factory preset sounds. I understand from the answer to this question that I can reset the device, but I'm not sure if the procedure described restores the synth to factory settings, or simply erases everything. Which is it? I am interested only in a factory reset - I don't want to end up erasing everything and then have no sounds at all.
According to this site, the D-5 cannot be reset, but the D-20 can.
From what I can tell, resetting the D-20 will put it back to factory defaults without losing all the sounds. (see the comments on this answer)