Tag Archives: HxC SD Floppy Emulator

E-MU Emulator II HxC Floppy Emulator

Ever since I got my EII I’ve been planning to add an HxC Floppy Emulator. These are some of the reasons:

  • One of the floppy drives doesn’t work and replacement drives are expensive
  • an SD card can hold a lot of floppy images
  • I don’t have a computer with a 5.25″ drive, so I have no way of transferring all the EII images I’ve got (could be solved if I get my Mac SE 30 and the serial thing working)

As the EII uses 5.25″ floppy drives, the connectors aren’t the same as for 3.5” drives. To solve this you basically have three alternatives:

  1. Create a new custom cable
  2. Create some kind of extension/adapter cable
  3. Modify the original cable

There’s a comprehensive manual from E M X P describing everything that you need to know about the HxC installation, including diagrams of the cables, whichever one you choose. Since I don’t like messing with the original one I chose to create one from scratch. I skipped the extension/adapter route since it would require a female 5.25″ connector, and I could as well create a whole new cable since I was messing with cables anyway. It’s also worth noticing that the cable is very long, almost a meter, which makes it nearly impossible to find a standard floppy cable and just add an extra 5.25″ male connector. In the picture below, taken from the manual, alternative 1 is the route I took. Alternative 2 shows the extension/adapter cable route.

Drawing of the 1) custom floppy cable that I make 2) The extension cable alternative. Screenshot from the E M X P manual (a must for everyone doing this conversion)
Drawing of the 1) custom floppy cable that I make 2) The extension cable alternative. Screenshot from the E M X P manual (a must for everyone doing this conversion)

Parts

  • About 1 m of 40-pin ribbon cable
  • Two standard 3.5″ floppy female connectors
  • One 5.25″ floppy female connector “34-way card edge connector IDC”
  • Lotharek REV F HxC drive (REV F is the 3.5″ floppy version). Buy it directly from Lotharek’s homepage. I should cost around €100, but I’ve seen “unofficial resellers” on eBay selling them for €150-200 – that’s a scam.
  • 5.25″ to 3.5″ adapter bracket, like this (I already had one from a computer chassis)
  • 4 pin Molex to floppy power adapter, like this (I had one lying around, probably included with a PSU)

Disassembly

First thing to do is to up open up the EII, which is a very simple process. Just a couple of standard Philips screws at the back and underneath. Then take the top of. Also locate the 4 screws that attaches the “floppy tower” to the chassis to remove it. 

At the middle of the main board, above middle C, a flat cable is folded, then going to the left, under the floppy tower and up to the drives. Remove this cable and use it as a model for the new cable.

Making the new cable

Prepare the flat cable by removing 6 of the wires to “convert” it from a 40 pin to a 34 pin flat cable. Then fold it at the exact same places and put the connectors at the same place, with one big difference – where the original cable has a 5.25″ for the upper drive, replace this with a 3.5″ connector. I used a vise to evenly squeeze the connectors to the cable. Make sure you orient the connectors the right way. Look for a little plastic piece between the 2nd and 3rd pins on the 5.25″ connector.

Swapping the faulty 5.25″ drive

The lower floppy drive didn’t want to load a disk that I know worked in the upper floppy drive.  Therefore I swapped them and carefully set their jumpers right. Now the lower one worked, but not the upper. Perfect, since my intention is to keep a working 5.25 floppy in the lower position and the floppy emulator in the upper position.

The faulty floppy drive with serial no 143922. Maybe it just needed cleaning, I don’t know –  I’ll keep it as a spare or something. It’s amazing the upper one works after 30 years…

5.25″ adapter and HxC metal work and jumper

I’ve used the HxC in lot’s of different samplers, and it has never properly aligned with the machine I’ve put it in. It always extends a couple of millimeters outside. So I decided to modify the HxC by drilling new holes in its metal chassis. For this I used 2.5 mm cobalt drill and used the adapter as a template. I chose this particular adapter since its pattern on the plastic matched the EII best.

Also set the jumper on the HxC to first position, as in the photos.

Floppy power adapter

For power to the HxC, a Molex to floppy power adapter was needed. Luckily I had a few of these lying around, probably included with some PC power supply, but never used. They can easily be found on eBay for a dollar or two. It’s simply connected to the Molex power connector that was previously connected to the now removed 5.25″ floppy drive.

Assembly

Simply reassemble the EII the other way around!

E-MU Emulator II bought on eBay

I just did something quite crazy – I bought an EII on eBay. It’s said to be working with the exception of the disk drives.  Those could and should be replaced with an HxC anyway. The big challenge will be shipping it to Sweden. To be continued….

Continued: It will be reshipped in a container since it’s larger than USPS allows. Will probably arrive around Christmas. Worth waiting for…

Bonus: someone has re-created “West End Girls” on an EII.  Fantastic!

Kawai K3 for Akai S900

I just swapped my Kawai K3 for an Akai S900 and a pile of cash. The K3 was one of those synths that are nice, but of some reason never is used. For that reason I decided to sell it.

I’ve also been working on converting Fairlight I/II/IIx disks to other formats. Akai S900 is one of them. So far I’ve used one of my Oberheim DPX-1s to playback the disks, but a lot of the S900 file formats aren’t fully documented. To be able to reverse engineer those formats I needed a real S900 to be able to set parameters. The DPX-1 is a sample player only, no parameter can be changed.

What’s interesting about the S900 and S950 is the fact that they have variable sample rates just like old drum machines like DX/DMX and Linn. This means that the S900  can play back sounds at any speed between 7.5 kHz to 40 kHz, and it does this by changing the clock. This could be described as manually turning a vinyl disk at different speeds. Most newer samplers uses the “drop sample” method instead. What this actually does is to throw away or duplicate samples. If a sound is to be played back at the double speed using the drop sample method, every second sample is discarded and never played back.

Next thing is to temporarily take the HxC SD Floppy Emulator from the Roland S-330 and put it in the S900 for testing my own generated disk images.

Roland S-330 power cable replacement

Lately my Roland S-330 sometimes hasn’t started when I’ve pushed the power button on the front. I’ve noticed that if I moved the power cable downwards it powered on, although a bit glitchy if I didn’t pull it hard enough. So when I had the S-330 out of rack I opened it up to see if everything looked alright near the power supply. And everything did, the soldering looked perfect. Moving the power cable made it turn on and off. I reckoned there must be some kind of breakage in the power cable, probably where the cable goes of the case.

I've unscrewed the metal plate in which a plastic part is mounted through which the power cable goes.
I’ve unscrewed the metal plate in which a plastic part is mounted through which the power cable goes.

As you can see the cable is run through a bit of plastic that is mounted on a separate metal plate. Removing the plastic was a major PITA, the trick is to rotate it a bit and using a pliers and push it from inside out. After the plastic bit is loose, it’s possible to open it with a flat screwdriver. As you can see in the photo below, the plastic piece has deformed the cable so it looks like a U.

The power cable has been U-shaped by the plastic piece, and it's here the power cable is damaged.
The power cable has been U-shaped by the plastic piece, and it’s here the power cable is damaged.

I bought a new power cable with a Euro plug, the original cable is an old style ungrounded plug.

The old plug (bottom) was an old style ungrounded one, the new cable (upper) has a Euro plug. This is the reason why I bought a new cable and not just cut away the damaged part of the old one.
The old plug (bottom) was an old style ungrounded one, the new cable (upper) has a Euro plug. This is the reason why I bought a new cable and not just cut away the damaged part of the old one.

To start with, I cut away the bad part from the plastic piece.

The plastic piece is modified, it's the part that's cutaway that damages the cable.
The plastic piece is modified, it’s the part that’s cutaway that damages the cable.
The evil part is loose.
The evil part is loose.

The I tried to unsolder the old power cable. That was unsuccessful and the tubing on the brown hot cable was damaged, so I fixed it with some yellow heat shrink tubing. I then cut the old power cable and solder it to the new one. Before I soldered I did remember to run the new power cable through all the bits and pieces that the original cable went through.

I tried to desolder the hot cable (brown one) without success. I damaged the brown heat shrink tubing so I put on some new. The new cable was solder together with the old one.
I tried to desolder the hot cable (brown one) without success. I damaged the brown heat shrink tubing so I put on some new. The new cable was solder together with the old one.
I mounted the new cable exactly as the old one.
I mounted the new cable exactly as the old one.

I powered it up and it worked perfectly. By the way, putting the plastic piece back was an even harder task than to remove it, but with a lot of patience I succeeded. The S-330 is now back in the rack, but before I reassembled it I took some bonus photos of it’s inside. Notice all the custom Roland chips and the HxC SD Floppy Emulator as well as all the different outputs.

Repair photos

Bonus photos