From Steve (& KAT):

The DD 720MB disks don't have the square hole on the opposite corner to the
record lockout slider, so if you cover this hole on a HD 1.44MB disk with
some tape, and format it as a 720MB it should work.
It's a pity Korg didn't make the i3 and i4s with a HD disk drive.
cheers
Steve

Bob Snelgrove wrote:
> 
> I keep a win 98 OS around just for formatting the i3 drives. Can't do it in
> XP :(

From Günter Nagler:

I wanted to suggest to use commandline
FORMAT /F:720 a:

but you are right that it doesn't help, XP doesn't format 720k by design
as Microsoft pages tell

From Jurgen Schuhmacher:

it is a common issue,
that HD-compatible disks sometimes
are not formatable in DD.

That is why i keept some packets of DD disks over the years.

Well , people should have a lood at the amiga coputer stores :
older amigas can't use HD drives due to there "BIOS" - so it
is not possible to replace the drive like I recommended in one of 
my emails. These old amigas have to stay with DD- drives AFAIK.

I do not know about the KORG Keyvoards so well - but what
happens, if you replace a DD drive by a HD drive ?
It might go one writing 720k only, but it should be possibly
to insert PC-formated HD disks then.

From Peter Inhat:

Hi all,

Just my few cents worth -

1. I know of a few people who have made High Density (HD) floppy disks
look like Double Density) DD disks by 'adjusting' the holes and so
fooling the drive. However it's not as simple as that. It will work but
don't rely on this being the only copy of your files because the 2 media
are actually physically different and you may get unexpected data
reading/writing errors (imagine being on stage, the crowd are going
crazy and your i3 won't load the next song!!). There's quite a bit on
the 'net about this but one reference is
http://www.pcguide.com/ref/fdd/mediaDensity-c.html
Basically the magnetic coatings are different because the higher density
disks use a lower magnetic field to write data to stop interference
between tracks. HD drives can switch between the 2 types of depending on
the media but I don't know whether this is done internally or by the
software talking to the drive.

2. Swapping the DD drive with a HD drive in your Korg - I don't know if
this will work. I'm guessing that a HD drive's default operation is as a
HD drive, not DD.

3. Following on from 2. above you won't be able to use a HD drive and
disks for EXTRA disk storage in the i2/3 since the software in the i2/i3
doesn't support the extra tracks, etc.

4. Formatting disks - 
> I keep a win 98 OS around just for formatting the i3 drives.
> Can't do it in XP :(

Don't forget that one of the functions in the disk menu of the i2/i3 is
to FORMAT a disk - you don't need to do it on a computer.

Regards
Peter


And a followup from Peter:

Hi Glen and everyone,
solution 1:
I don't know about XP but I assume it's the same as the other windows -
as long as you have a DD disk, put it in the drive, double click My
Computer, right click on   31/2 Floppy (A:)  and slide down to Format
...
Under 'Capacity' you can select 1.44Mb or 720Kb.

solution 2:
Format all your disks on the i2/i3 (go to DISK menu).  The computer will
recognise the size correctly so just drag your files there as normal.

Peter