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Roland Sound Canvas SC-55

Back in the day, my MIDI setting of choice was either Adlib, OPL3 or Sound Blaster FM. I only ever had a Sound Blaster 16 card and so never experienced any of the Sound Blaster 32/64/Awe Cards or external MIDI devices. Over the years since, I've learnt about MT-32 and wanted to try and find a real device. Unfortunately, they're neither cheap nor easy to find! A friend had also told me about the Roland Sound Canvas range and it seemed that these may be easier to find as there were more models released.

Stumbling across one...

I happened to be in Japan for a friend's wedding and, whilst travelling the countryside, scoured any recycle shops that I ventured past. It finally happened that, in one of the last shops in Kumamoto, I found a Roland Sound Canvas SC-55. It was 950 yen and was in the "Junk Corner".

I packed it into my suitcase, but researched it for the rest of the trip. One tidbit that I came across indicated that the internal battery had leakage issues (I anxiously wanted to check this, but didn't have the tools or the time.) The Sound Canvas Wikipedia page also pointed out that: "units without GM logo technically not GM compatible." Turns out mine didn't have the logo! Must be one of the first off the production line? I wonder if I'd even be able to play general games or only Sound Canvas games?

I then started getting lost in further articles describing the differences between the revisions of the SC-55. Nerdly Pleasures had a great article on the nuances here: First Generation Roland Sound Canvas Devices, which then lead to the Vogons forum: Apparently not all GS-only sc-55s are the same, some are GM. One poster noted that if you have an SC-55, you wont be disappointed as, regardless of the nuances, you'll still get quality music and games suited for the device will sound amazing.

Moisture Damage?

I noticed, when I first picked it up off the shelf, that the rear plugs were slightly oxidised. The top shell also had rust along the front edge. Opening it up saw that there was no physical damage on the board. Powering it up saw that the front panel buttons only wanted to work every-so-often. The first thing I did was find replacement microswitches from Jaycar who had a suitable (and really clicky!) substitute. Note that the replacement is half-width! Jaycar also had the full-square-shape types, but these had 4 pins and didn't match the PCB holes.

You can see above that column 3, row 4 had damage. I removed it and replaced it with the new slimline switch. Worked perfectly.

I ended up purchasing 16 of the half-width switches to replace all on the front panel.

Battery Leakage

Yup, coin-cell batteries leak too. When I first opened the box I saw that the battery was jammed in and corroding. This battery provides a trickle of power to persist storage of the current device configuration (panning, levels, key offsets, etc...) which is great if you're composing... but really, you want it to reset each time when playing games, so I was very happy to remove it.

You'll get a notice when the device powers on, but it's easily ignored.

Power Supply

The unit wants a standard DC jack with 9v at 500mA. Note that the polarity is the typical Japanese reverse! Positive on the outside.

Jaycar to the rescue yet again: The power supply had enough amps and a reversible plug on the end. I didn't even have to re-wire it. I am concerned though.. these adapters make it REALLY easy to plug in the power in the wrong way around!

Resetting/Testing

Before even trying composition software or games, I wanted to ensure that the device actually worked. 900 yen (along with the "not tested" label) meant that I could be in for a sad surprise when it chose to produce no sound. There is a demo mode on the device that plays two stored songs, so I attempted to get into this, after resetting the device.

To reset and enter GS mode, hold the left Instrument button and then hit power. Hold the right to reset (and enter) MT-32 emulation mode. Hold both to reset totally and return to GS.

The two sample songs only work in GS mode, so if you're in MT-32 mode, it'll first ask if you want to reset back to GS. This slightly confused me at the start as I thought the buttons were more damaged than first seemed; the Instrument buttons were meant to reset settings, not the Part buttons.

Anyway, to play the demo songs, hold down both Part buttons then power on the unit. You can select the song via either Part arrow and then hit the All button to play.

Using a MIDI keyboard

This 'just worked'. I'd received a midi cable with this keyboard and it was plugged from the 'out' of the keyboard to the 'in' on the front of the SC-55. Everything just worked, including all the controls on the keyboard. The keys are also perfectly pressure-sensitive... so whacking them harder really tested out the speakers!

MIDI Out via AWE64 Value

Now the fun was to begin. I pulled out the old PII-500 with an AWE64 Value sound card. The card has a whole lot of extra software and soft-synths to help with MIDI playback. This means that there's extra configuration required to get the MIDI-Out to actually work. By default, midi is routed into the AWE64 driver's 'soft synth switch' which then redirects and modifies the midi signals as configured.

I wanted none of this and set the output straight to the port. With the cables connected, I heard absolutely nothing. I mucked around with further settings... but had zero success. This 'SC-55 Howto' at Vogons indicates that output 'should just work'... not for me!

MIDI Out via SB32 PNP

This time I booted up my old 486 DX 2/66. Screamer has a nice audio setup application and allows you to test your configuration very quickly. Unfortunately, I couldn't get any midi-out at all. Is it my cable?

MIDI Out via Edirol UM-1EX

This device came with the keyboard and I'd forgotten I had it. A friend had told me they used their external midi devices in DOSBOX on new hardware, so I thought I'd give it a go. After switching off Windows 10 driver signing, I was able to get this installed on my main laptop. I then set DOSBOX to use the 'UM-1' device and loaded up Transport Tycoon.

Success! The audio sounded terrific! Of course, DOSBOX is emulation, so multi-tasking made the music slow down and sound hilarious... actually, that might just have been because the laptop was in power-saving mode and didn't want to spend all cycles on DOS emulation.

Joystick port on ISA controller card?

Nope, don't bother... it won't work! That joystick port is hardly good for one joystick with two buttons. You'll need a real soundcard with a standard gameport as they have the correct pins wired up.

MIDI-Out Cables

Back to the old PCs, it was time to work out why the MIDI wasn't sending out. The Edirol device above has nice lights on it to show that data is flowing, so I thought I'd try and add the same to my midi cable. There's a great diagram here that shows where the LEDs should be placed. Turns out they're just on the ground lines for each MIDI in and out.

Following the diagrams also available on Vogons, I realised that the resistors on the MIDI-OUT lines were way too high. 1.2kOhm vs the 220ohm listed in all diagrams I'd found. I quickly replaced these.

And then...

Well shit... Screamer Sound Setup just started sounding perfectly on port 330! Who would've thought you'd have to replace resistors inside a plug housing to get vintage midi signals to flow?

The Settlers intro sounded perfect as well.

What a steal for 900yen!