The Mac SE is a more advanced Mac that the one Kurzweil expects. If "About this Mac" says it has 4096K, then it contains eight times the required 512K. No need to open it or do anything more.
400K format and 800K format can only be read/written by Macs with a built-in Diskette drive. These Macs used a variable-speed motor that was never adopted by other manufacturers. But the diskettes themselves are the same 2D or 2DD diskettes used by comparable IBM systems as 720K diskettes. If you can get IBM-compatible 720K diskettes, the Mac can read, write, and reformat them for its own use.
The oxide on HD diskettes is different. They are NOT interchangeable. If written as 2DD diskettes, the data can begin to decay within minutes, and may be completely unreadable in as little as an hour. (This is more of a problem using 2DD as if they were HD.)
I have one other question: The serial port on the back next to the SCSI port looks to have 19 pins and from what I know about the cable that is used to interface with the Kurzweil on the Mac side has 8 pins and the Kurzweil 37 pins. Called a QLS 3 meter cable it works with the QLS software that let's you edit samples on the Kurzweil K225 RMX. From wiki it's described as:
"A QLS cable for connecting the Apple/Macintosh DB-9 or Mini-DIN 8 (typical) or Geoport port to the Kurzweil DB-37 computer jack (DB-9 Male or Mini-DIN 8 Male or Geoport Male to DB-37 Male) -or- the PC DB-9 to the Kurzweil DB-37 computer jack (DB-9 male to DB-37 male)."
The SE has a port that is 18 or 19 pins. Does this suggested cable use only 8 or 9 pins?
The round ports about the size of the keyboard/mouse ports with about 8 pins are MiniDIN-8 serial ports, one marked printer (has a slightly higher priority) and the other marked modem. The older Macs used the much larger DB-9 for the same purpose.
The 19-pin port is for an additional external diskette drive that uses all 19 pins. I don't recall ANY other peripherals that plug in there.
The DB-25 is not a printer port, it is a SCSI port, and if you plug a Printer (or any non-SCSI device) in there your Mac will not boot.
You used a key word in your description. The word is 'Geoport.'
We need to break down your instructions. "A QLS cable for connecting the Apple/Macintosh DB-9 or Mini-DIN 8 (typical) or Geoport port to the Kurzweil DB-37 computer jack (DB-9 Male or Mini-DIN 8 Male or Geoport Male to DB-37 Male) -or- the PC DB-9 to the Kurzweil DB-37 computer jack (DB-9 male to DB-37 male)."
The DB-9 was on the computers prior to the SE. With the SE, Apple moved to a new style of connector. The keyboard on a Mac Plus was a phone connector. The keyboard on the SE was an ADB, or Apple Desktop Bus. That port could connect to things like a weather station or other input devices. The comm ports, namely printer/network port and modem port, were also new style round plugs. They were similar to the keyboard plug in size but eight pins instead of four. IBM compatibles copied that style of plug but made a slight change to the keyboard plug to distinguish it from a Mac keyboard plug. The cord also looks like S-video ports on newer digital cameras.
The Geoport was an attempt to skip having a modem. The idea did not catch on. Any device that was designed for the geoport was intended for the modem port. If you have a cable that fits into your Kurzwell K225 RMX and fits into the modem port on the SE, that will match the instructions you have quoted.
Hi folks, please try the Kurzweil K250 yahoo group. A lot of knowledge there and even a lot of software in the files section. Best place for every K250 owner.
You cold also contact me directly, glad to help. I have two K250 and one RMX, connected to old trusty Macs IIci, which are indeed great machines in combination with a K250. Recapped them, they run since 23 years now. :-)