Repairing and Restoring the Roland R-8 Human Rhythm Composer

I set out to get a fully operational Roland R-8 Human Rhythm Composer.  The main issue when I stared this 11 part restoration video project was to fix what I beleived was a damaged display.

Roland R-8 - Assessment of the project - Restoration Part 1

I open this series by finally admitting that my Roland R-8 has been languishing in storage for years while I kept promising myself I'd sort it out. I've got two Roland R-8 drum machines to work with: my original, which I've kept in reasonably good condition, and a donor unit I picked up as part of a job lot a couple of years ago. Before I pick up a screwdriver, I want to lay out exactly what state each machine is in and what the plan looks like for bringing one fully working example back into the studio.

I also take a moment to talk through a bit of history, since I think it helps to understand why this Roland R-8 is worth the effort. Roland released the Human Rhythm Composer back in 1989, and there were actually three versions issued: the original drum machine, the card-reading R-8M module, and the later R-8 Mark II. What made the original so clever at the time was its velocity sensitivity, letting you play softly or with real force, which is exactly why Roland gave it the "Human" name rather than simply calling it the rhythm composer.

The most frustrating fault on my own Roland R-8 is the display, which only shows half the information it should, while the donor machine's screen works perfectly despite the rest of its casing looking far worse for wear. My plan is to swap the good screen across, service the pads, and eventually sell the leftover Roland R-8 parts on rather than let them go to waste. I also touch on the awkward proprietary power supply Roland used, which is notoriously hard to source these days.

Roland R-8 - Accessing the drum machine - Restoration Part 2

This instalment is all about getting inside the case, which starts from underneath with six screws before I work my way round to the panel at the back. I've got a habit of bagging and labelling every screw as it comes out, mostly because I know from bitter experience how easy it is to forget which one goes where once the machine is in bits on the bench.

Once the rear plate lifts away, I find a bit of surface rust that needs noting for later, and then I start peeling back the layers one at a time to reach the screen I actually want. The Roland R-8 is built with everything bolted to everything else, so removing the battery first and working through the ribbon connectors and cabling with real care is essential if I don't want to snap anything delicate along the way.

By the end of the video I've got the main board free, along with the strike pad assembly, the button board and the display all separated out, plus a metal shield removed from underneath. It's a fiddly job with plenty of easily missed screws, but it leaves me with proper access to every major part inside this Roland R-8, ready for the display swap I've been planning since part one, and it's given me a much better feel for how the Roland R-8 is put together layer by layer.

Roland R-8 - Removing the display from the donor R-8 - Restoration Part 3

With the case open, this video is dedicated to lifting the screen out of my donor machine. I take the plastic shield off first, held down with just a few screws, and then work through another set to free the display itself, pausing along the way to photograph everything since there's so little documentation about this particular part on the internet.

What becomes obvious once I've got it out is exactly why this screen is so difficult to replace. Roland etched a unique pattern directly onto the glass when they designed it for the R-8 range, so there's no modern LCD or OLED panel that can simply be swapped in as a substitute. It's a proper Sharp-made unit rated at 24 volts, and until someone reproduces that etching, this remains the only viable route to a working Roland R-8 display.

I round the video off by explaining that I'll repeat exactly the same strip-down on my own cleaner Roland R-8 off camera, since there's no need to show the process twice. That sets things up nicely for the next stage, where the donor's screen finally gets fitted into the target Roland R-8.

Roland R-8 - Installing the display to the target R-8 - Restoration Part 4

Having stripped the target Roland R-8 off camera, I pick up here by lifting its faulty screen out and fitting the donor display in its place, careful not to overtighten the screws that bite into fragile plastic mounting posts. Along the way I notice a ferrite ring fitted to the cable that looks like a factory afterthought, and a date stamp suggesting the two screens were made roughly a year apart.

The genuinely surprising moment comes when I power the machine up expecting the fault to be fixed, only to find the exact same problem still showing on screen. That tells me straight away that the display was never the issue, so I turn my attention to comparing the two circuit boards instead, spotting differences in chip sockets, cabling and revision numbers that point to one board being a later design than the other.

I run a couple of swap tests, pairing each display with each board, and both screens light up perfectly once matched with the donor board. That confirms the fault sits with the driving circuitry on my original board rather than either display, giving me a clear route forward as I plan the rebuild of a single, fully functioning Roland R-8 from the best parts of both machines. It's a small but important breakthrough for this Roland R-8 restoration.

Roland R-8 - Removing the rear plate for restoration - Restoration Part 5

Now that I know which board is going where, this video covers the cleaning I need to do before reassembly begins. I start with the donor board, using isopropyl alcohol to lift years of dust from the card slots and edges, then work over the sliders with contact cleaner and try an old trick with aluminium foil and WD40 to shift the surface rust.

Turning the board over reveals a missing mounting pillar, which I transfer across from the other machine, along with a rather more stubborn problem: rust creeping across the metal backplate. Once I look closely, I realise it's spread far enough that a quick respray isn't really going to cut it, and the only proper fix is to strip both plates right back to bare metal before repainting.

The rest of the video is spent working through the screws holding that plate in place, including a fiddly bent-over section Roland added purely for extra strength around the card slots on the Roland R-8. By the end I've got both circuit boards free of their backplates, ready to prime and paint, which sets up the next stage of getting this Roland R-8 properly weatherproofed against future corrosion.

Roland R-8 - Repainting the Backplate - Restoration Part 6

This video picks up a few months later with the job of treating that rust I identified previously on this Roland R-8. Both backplates need attention, but the donor machine's plate is in a genuinely dreadful state, pitted right through on both sides despite having spent its life protected inside the plastic casing. My aim throughout is simple: strip everything back to bare metal so I know it won't creep back once the Roland R-8 is sealed up again.

I try Nitromors first, leaving both panels coated overnight, but it barely touches the paint, so I move on to sanding instead. A palm sander handles the flatter sections reasonably well, though it struggles with the indented areas, and a Dremel with a sanding wheel isn't much better. It's only once I switch to a wire brush attachment that the old paint finally starts coming away properly, chewing through several brush heads in the process.

With both plates down to bare metal, I rig up a makeshift spray booth at the bottom of the garden using some barrier fabric to protect the fence, then give each panel a coat of matte black paint. By the end I've got two freshly protected backplates ready to go back into their respective machines, which finally sets the Roland R-8 rebuild moving again after a fairly bitty few weeks of filming.

Roland R-8 - Reassembling the circuits to the backplate - Restoration Part 7

With the paint properly hardened off, this video is about remounting each Roland R-8 circuit board onto its freshly sprayed backplate. I've got two complete sets sitting in storage, so the job is really just working out which display pairs with which board before bolting everything back together, securing each one with the little metal bracket and grub screw that hold it in place.

I put the first board back together on camera, then admit to doing the second one off screen after a recording mishap, though I do point out the telling difference between them: one carries a revision stamp of 00 and the other 01, with the newer Roland R-8 board using socketed chips and a plug-in ROM rather than components soldered directly down. It's a small detail, but it helps explain why the two machines have behaved so differently through this whole process.

I finish by getting the power supply out ready for the next stage, where I'll test each display against each board properly rather than relying on memory. Progress on this Roland R-8 has been slower than I'd like, partly down to a change of job, but the finish line for a working unit finally feels within reach.

Roland R-8 - Cleaning the top for assembly and assembly - Restoration Part 8

This video starts with the crucial test of matching each Roland R-8 display to its correct board, powering each combination up in turn until I find the pairing that brings the screen fully to life without any errors. Once that's settled, I know exactly which board and backplate need to go into the better chassis, and I can finally start building one complete, working Roland R-8.

Turning my attention to the top panel, I spot a rusty strip along the bottom edge that's worse on one unit than the other, so I strip it out to sand and respray separately. That discovery leads me to open up the lid assembly, since it's clearly picked up dust and grime even while sat closed in storage, and I decide it's worth giving the whole thing a proper service rather than just closing it back up.

The rest of the video covers a full clean in soapy water, a gentle wipe of the strike pads with isopropyl alcohol to lift the surface marks without disturbing the rubberised compound underneath, and a careful reassembly of the buttons and control board. It's more work than I'd planned for this stage of the Roland R-8 rebuild, but it leaves the top assembly properly clean and ready for the backplate to go back on next.

Roland R-8 - At last the final assembly - Restoration Part 9

After the unexpected detour into cleaning the lid components, this video finally brings everything together into one complete Roland R-8. I start by refitting the foil shield and its ferrite-choked cable, working out from memory and a few reference photos exactly which screws secure the shield, the main board and the backplate, deliberately leaving them loose to start with so everything can settle into alignment properly.

Connecting the ribbon cable back to the Roland R-8 display takes real care, since it's such a delicate connection, but it slots home without too much drama once the shield is giving it enough support. I also discover both coin cell batteries are flat, so those get replaced using a bit of kitchen towel to avoid handling them directly, before I turn my attention to treating a little surface rust on the inside of the rear case with the same foil and isopropyl alcohol trick I've used throughout this project.

With the case, lid and back screwed down and the sliders finally treated with contact cleaner, I flick the power switch and, once I remember to actually turn it on, the Roland R-8 boots up exactly as it should. It's a genuinely satisfying moment after so many months of work, even if there's still a second, more troubled machine waiting in pieces for its own diagnosis.

Roland R-8 - Clips from the cutting room floor - Restoration Part 10

This video is a compilation of Roland R-8 footage that didn't make it into the main nine-part series, covering smaller jobs I felt were worth sharing even though they didn't fit the main narrative. I go back through clips of restoring the foil shield, scrubbing both circuit boards with a toothbrush in the kitchen sink, and polishing the strike buttons and control surface until they genuinely shine again.

A fair chunk of the video focuses on the metal strike plate that sits behind the Roland R-8 pads, giving that assembly the strength it needs to survive years of enthusiastic drumming. Both the donor and target plates had picked up surface rust, so I work through wire brushing, sanding and a wipe with isopropyl alcohol before spraying them properly in a makeshift outdoor paint booth, battling a rather breezy day in the process.

I also cover the backplates in more detail here, showing the full sanding and wire brush process needed to get into the corners and creases a sander alone can't reach, followed by several coats of paint to make sure everything is properly protected. None of this is glamorous work, but it's exactly the sort of unglamorous care that keeps a Roland R-8 running reliably for years to come.

Roland R-8 - So does it work - Restoration Part 11

After ten videos of stripping, cleaning and rebuilding this Roland R-8, this final instalment answers the only question that really matters: does it actually work? I power the machine up and watch the familiar space invader animation appear, followed by a fully functioning screen, which is a proper milestone given that a faulty display was the whole reason I started this project in the first place.

With headphones on, I run through the full range of built-in sounds, from kick and snare through to crash and ride, confirming that the velocity-sensitive pads still respond nicely to a lighter or heavier touch even after everything they've been through. I also talk a little about the PCM sample architecture the Roland R-8 shares with Roland's D-50 synthesiser, which goes some way to explaining that distinctly compressed, very eighties character to the kick and snare sounds.

I finish by demonstrating the pattern and song modes, flicking between a handful of preset beats and explaining how the screen's various boxes indicate mode, sound bank and step position, awkward as that display can be to read at a glance. It's a genuinely satisfying place to end the series, with a fully restored Roland R-8 ready to earn its keep in the studio this year.

Summary

Completing the work on the Roland R-8 has resulted in one fully operational drum machine which is now in the studio and one machine still in peices waiting for me to diagnose the additional issues that were found.