Top 5 Common Repair and Replacement Projects for your Alesis HR-16

I love the Alesis HR-16 drum machine, it has great set of realistic built-in drum sounds, does all the MIDI stuff you expect, is a fantastic circuit bending target, and is actually very easy to program. I have owned a bunch of them over the years and the first thing I always have to do before modifying them is fix something. Most of these repairs are pretty easy, kinda cheap, and applicable to Alesis MMT-8 (and really most music gear of this era), too.

In this short post I’ll run through some of the most common issues and their fixes. From non-responsive buttons and failing displays to patterns not being saved or no sound at all. While these repairs DO fix the majority of the affected machines, depending on the level of abuse, your HR-16 may be beyond repair. That said, these drum machines are pretty hardy, Made in the USA, sound great, and worth the repair attempt.

Released in 1987, some of the early Alesis HR-16 examples are pretty beat up, non-working, and otherwise “dead”. Or are they?

1. MY ALESIS HR-16 has YELLOW BUTTONS
   This is a purely cosmetic fix, but one that just about all the first and second generation machines can benefit from. Lots of things cause the buttons to yellow, everything from smoke to sunlight, and that is makes the fix so interesting. If you fill a clear glass with hydrogen peroxide and your buttons, then place the cup in direct sunlight for a couple days, the yellow disappears. I was shocked to see how well this worked as most online instructions wanted me to use hair developer, plastic wrap, and a UV light. Experimentation wins again.
2. MY ALESIS HR-16 ISN’T SAVING DRUM PATTERNS ANYMORE
   Your internal battery is dead. The Alesis HR-16 takes a 3.6 volt, axial-lead, lithium battery. Some folks replace with a coin cell battery and holder, but those requiring changing more frequently. Use the correct battery and you get around 10 years pattern retention.
   Replacement is pretty easy if you know how to solder, if you don’t, it is possible to pull up the circuit trace to the battery and damage the circuit board. I suggest adding new solder to the old battery solder points before you attempt to de-solder, this helps to melt the older solder making removal easier.
   Need a battery? I like the XENO from Battery Junction.
3. MY ALESIS HR16 HAS NON-RESPONSIVE BUTTONS
   This is very common is older musical instruments that use silicon keypads for buttons, like the Alesis HR-16. Other examples are the famous Hing Hon EK-001, most Casio and keyboards, too. What happens is the carbon coating on the silicon pad (the pads make the internal connection over a dual pair of circuit traces) looses it conductivity; so when you press the button, nothing happens.
   The Fix is to re-coat the buttons with a conductive paint. First, wash button sheets in warm soapy water, dry, then use a q-tip and rubbing alcohol t sterilize the pads. This helps the conductive paint stick.
   What conductive paint do I use to repair Alesis HR-16 buttons? I have recently started using SilexCore Conductive Paint (can be found on Amazon), it does the trick and is far easier to use then the CircuitWriter Pen (which dries out quick, sometimes even before you get it open) method that also works.
   Be sure to coat buttons evenly, and let dry completely before re-installation.
4. MY ALESIS HR-16 HAS DIMMED or NO DISPLAY
   These LCD displays tend to fade out over time, often you need to angle your head in a funny direction to read them. Luckily the folks over at CircuitBenders.co.uk have sourced (in multiple color combos) and sell them at a very reasonable price. They look great, are super easy to install, and are a very affordable upgrade to your drum machine.
5. MY ALESIS HR-16 TURNS ON BUT MAKES NO SOUND
   This could be a couple of things, so I always like to start with cheapest/free option.
   A. Your output jacks are dirty, overtime the part of the jack that connects to the tip of your plug can get covered in corrosion or get so dirty that it fails to pass sound.
   The Fix: Clean the jack with a Q-Tip and rubbing alcohol, or De-Oxit, or similar product. Be sure to let the jack dry completely before testing.
   B. Your output jacks are deformed, overtime and sometimes from abuse, the internal connection to the tip of your plug can get bent out of shape. Sometimes you can grab it with an angles solder assist tool, sometimes the jack needs to be replaced. It all depends on what the cause of the damage is.
   C. Your volume pot is dirty or broken, these slide pots are open at the top which makes it really hard to keep dirt, dust, and other debris out of the travel area. Finger grease, smoke, and other funky, sticky crap also gets in there making the pots really gunky. Sometimes De-Oxit is enough, sometimes the pots are so damaged that they need to be replaced. Another common issue with these slide pots is the slider knob can break off, usually you can use a small screw driver to adjust it.
   If you need to replace the pots, Mouser has the best deal on a direct replacement, the parts numbers are as follows.
   Alesis HR-16 Volume Slider: PS60-20MCC1BR10K
   Alesis HR-16 Data Slider: PS60-10MCC1BR10K

Missing the slider knobs for you Alesis HR-16? My 3D printed version is available on Reverb

These 5 items will help you repair most of the problems with malfunctioning Alesis HR-16 drum machines. Like i said, depending on the level of abuse, your HR-16 may be beyond repair. I have brought several back from the dead. You can, too.