Hello to all.  In regards to the difference in HD (high-density) and
Non-HD discs -- Non-HD discs have a different magnetic coating on the
disc itself, wherein an HD disc has a much denser coating on the disc
itself (which is why the disc is labeled HD for "High Density").

That is why trying to use an HD (1.44M) disc as an DD (double density
720K) disc will cause problems, due to the fact that the HD magnetic
material on the disk requires a higher current (from the disk drive
head itself) to successfully record onto the disc.

Both SD and HD 3-1/2" disks are double-sided.  Years ago when 5-1/4"
floppy drives were used, there were single-sided and double-sided disks.

Depending on the version of the software in the PDS-128 control box,
it may have the ability to format diskettes in the drive itself.  Here
is one way to test this:

1. Turn on the system and insert a _known good_ recorded disc.  You
can use a pre-recorded PianoDisc disc to do this.  Make sure the little
slider on the disc itself (bottom left-hand corner when look at the
label side of the disc) it set so the little hole is OPEN.  This will
prevent erasing the disc.

2. After the control box reads the disc, repeatedly press the "Mode"
button (between the 1 2 buttons and 3 4 buttons) until you see
something on the display relating to disk functions.  It could show
something like "FREE NAME FRMT" or possibly "DISK" as one of the
options.

3. If it shows "FRMT" as an option, select it.  Follow the display --
I believe it will ask you if you want to format a disc; it will then
ask you to insert a disc and then follow the prompts.

Note: If it asks you to format a disc this way, the only discs you can
format are SD (720K) discs, which are getting VERY difficult to find
now.

4. If "DISC" appears, select that, then it will ask you if you want to
format a disc, and then ask you if you want to which type you want :
720K or 1.44.  Make sure you insert the correct disc for the format you
have selected!

In regards to PC formatted discs -- The later software in the
PDS-128(+) control boxes could read PC-formatted discs with SMF
(Standard MIDI File) MIDI files saved onto them.  It will also play
SMFs (if in format 0 (zero)) if there is a "Acoustic Grand Piano"
patch change at the beginning of the file.  It will then route the
piano part (regardless of channel) directly to the piano, and the
piano will play from the SMF.

However: A PC can _not_ format a PianoDisc-format disc nor can it read
the same type of disc.  That requires special software.

Hope all of this helps!

Mike Carey