OMNIFLOP  -or-  SDISKW  -or-  "dd"???

Using OmniFlop, SDISKW or "dd" depends on the method you create sample disks or image files. Each one has an advantage over the other

OmniFlop has a more user‑friendly GUI Windows interface and also works with other sampler/synth brands such as Akai, E‑Mu, Ensoniq, etc...
However, it does not support external USB drives. This requires OmniFlop to be used only on older model PC's with older floppy disk drive hardware. The big advantage OmniFlop has is that it's able to read *.OUT, *.IMG, *.S50, *W.30 and other Roland sampler disk image files for use with some GOTEK USB/FDE devices

SDISKW v1.7 offers the advantage of being able to work with either an internal 3.5" Floppy Disk Drive (FDD) -or- an External USB 3.5" FDD allowing use on more current model PC's. SDISKW v1.7 is able to load an *.OUT, *.IMG, *.S50, *.S33, or *.W30 disk image file and write it onto a physical 3.5" floppy diskette. However, it will not allow you to read Roland 3.5" Floppy Disks and save it as an *.OUT, *.IMG, *.S50, *.S33, or *.W30 disk image file (i.e. saving a disk image file onto a hard drive, SD Card, USB Stick, etc... will not work)

"dd" is a command line, Terminal window utility and some people might not find it user friendly. It works on Mac with external USB disk drives


I installed and tested OmniFlop Version: 3.0 with Windows XP (SP3) and also Windows 7 Ultimate (32‑bit) and various internal 720KB 3.5" FDD's

OmniFlop requires an Internal 3.5" 720KB 3.5" FDD with a 34‑pin ribbon cable. External and USB FDD's are not supported !!!

In order to get OmniFlop to work with the Roland disk formats, you will need to install the OmniFlop drivers which are included in the *.ZIP file. I followed the instructions in the PDF file and the new driver installation was hassle‑free*

     OMNIFLOP DOWNLOAD OmniFlop can be downloaded here   S-50 / S-550 3.5 ICON

*One thing I would watch out for is that the OmniFlop driver will overwrite your existing Windows Floppy Disk Drive driver and will also overwrite your Floppy Disk Controller driver. You might want to play it safe and back‑up these two driver files prior to installing OmniFlop. The original drivers for both of my Windows systems (WinXP Pro SP3 and Win7 Ultimate 32‑Bit) were located at:



My first attempt at using OmniFlop failed because the MITSUMI Model D353M3D 3.5" FDD was incompatible with OmniFlop and the Roland disk format. I wanted to point out this particular FDD because the specifications say this model is able to read/write 1.44MB disks and also 720KB disks. However, for unknown reasons, the 720KB mode does not work with OmniFlop and this model

So... I replaced it with a different brand and model, the NEC FD1231T. This new one works great. This model reads/writes both 720KB and 1.44MB disk formats. I have been able to create Boot and Sound Disks for the S‑50, S‑550, S‑330, W‑30 and S‑760 without any issues

Update - March 2018 - I've since tested two other 3.5" FDD's which also work well with OmniFlop



  • To create a 3.5" floppy disk image file to share with others
    • Insert a 3.5" diskette into the computer's disk drive (with the write protect tab on!)
           Example: Insert the diskette labeled "RSB_5504_5 - Industrial Strength Techno" into the PC
    • Run the OMNIFLOP utility
    • Choose Read Disk
    • Choose 80/2/9x512 Roland S5xx, S7xx, DD‑disk 720kB then click the NEXT button
    • Choose a unique filename (Click the BROWSE button if you want to use a different directory)
    • Choose the sampler format you are using
    • To create an S‑50 diskette, choose S50 image (*.S50). To create an S‑550, S‑330, S‑760 or W‑30 diskette, choose Roland S5xx, S7xx, DD‑disk 720kB image (*.OUT)
           Note: You can't use an S‑50 diskette to create an S‑550, S‑760 or W‑30 disk image file. All disks must remain true to their respective sampler model
    • The disk image file you just created (*.S50, *.S55, *.S33, *.W30, *.out, etc...) can now be uploaded and shared with others. When someone downloads the disk image file, they can use OMNIFLOP, SDISK, SDISKW, SCAT, SAMATARI or another sampler utility to create their own S‑50 or S‑550 3.5" sampler sound library diskette
      • To let others know the sampler your new disk image file is intended for, it's good practice to rename the file extender to *.S50, *.S55, *.S33 or *.W30

S-50 / S-550 SDISKW

Special thanks go out to Alexandre Souza for compatibility info about this external USB FDD!

I installed and tested SDISKW Version: 1.7 with Windows 10 Pro (64‑bit) using an External 3.5" USB Floppy Disk Drive (IBM Model#: FD05PUB). This IBM USB drive is able to read/write 720KB 3.5" disks for the S‑50, S‑550, S‑330, W‑30 and other select Roland Samplers, Synths and Sequencers. When pressing the READ button from the menu, the program will automatically detect the density on the 3.5" floppy disk. Likewise, the WRITE button will autoselect and format the diskette for the proper density. SDISKW v1.7 also worked with Windows XP (SP3) and also Windows 7 Ultimate (32‑bit) and the three internal 3.5" floppy disk drives shown above

To create a physical 3.5" floppy disk from an *.OUT, *.IMG, *.S50, or *.W30, disk image file, insert a 3.5" floppy disk and select A: or B: then press the Write button. Choose an *.OUT, *.IMG, *.S50, or *.W30, disk image file and the program will format and write a new 3.5" floppy disk

Note: SDISKW v1.7 will not allow you to read Roland 3.5" Floppy Disks and save them as an *.OUT, *.IMG, *.S50, *.S33, or *.W30 disk image file (i.e. saving a disk image file onto a hard drive, SD Card, USB Stick, etc... will not work)

     OMNIFLOP DOWNLOAD SDISKW v1.7 can be downloaded here
          NOTE: The website hosting the SDISKW v1.7 download disappeared at the beginning of 2022
          Access via the Wayback Machine also shows a blank webpage
          I'm not sure if this is temporary or not so I am adding a copy I download from way back in 2017


No installation is required for using the "dd" Utility on a Mac and everything you need to know is explained here


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