Today I’m sharing a few pictures of a repair on a Yamaha CLP-370 with sticking keys, clunking sounds, and dead keys. But this could happen on most Yamaha Clavinovas. See my Digital Keyboard FAQs for more!
Hammer Rest Felt (Sticking and Clunking)
One of the most common complaints I receive from customers is that their keys are making a noisy thunk when the release them.
This is typically caused by worn key felts, and in particular, a worn hammer rest felt. In fact, this problem is nearly ubiquitous in Clavinovas, and many Yamaha portables, that are over a decade old. And of course, this wear can be dramatically worsened by spills or foreign substances finding their way into the keyboard!
Just a friendly reminder not to set your soda on your valuable Clavinova!
This particular CLP-370 had a soda spilled in it, which also meant that several keys were sticking quite badly. In the CLP-370, this is part V7640101, and is readily available through Syntaur. See below the difference between the original hammer rest felt, and the replacement:
Oh boy! That’s one worn hammer rest felt. The worn felt is, obviously, below, with the replacement above it.
And the Dead Keys
Yamaha Clavinovas and, in fact, most digital keyboard instruments, use contacts underneath the keys to sense how quickly you press them. If those contacts misbehave, they can either imagine you’re playing at maximum intensity, all the time, or they can miss that you’re playing at all! In this case, the Clavinova wasn’t registered key presses at all.
On disassembly, I observed that soda had found its way onto the contact circuit boards. See the image below:
A closeup of a soda spill on the vias. Exposed Yamaha contacts can be seen mere millimeters away.
Here’s a closeup of some similar damage on a Yamaha P125:
A closeup of a Yamaha contact from another angle. Here, you can see pocking in the trace underneath the surface of the circuit board. A little bit of a rust on a solder joint stands out like a flag to help locate the damage.
Depending on where the damage is located, it can be cleaned and bypassed. It’s often less time-consuming (and more permanent) to replace the contact board.
This particular Yamaha P115 had been nonfunctional since a lightning strike occurred near the owner’s residence. I found the primary issue was damage to the main DM board, which is prominently featured in the accompanying image. Additionally, the volume slider and several buttons exhibited significant damage. While it’s uncertain whether this resulted solely from the lightning strike or if a liquid spill also contributed, the extent of the damage is noteworthy.
Lightning strikes can cause substantial harm to electronic devices through various mechanisms. Nearby lightning strikes induce power surges—sudden spikes in electrical energy—that travel through power lines and into connected devices. These surges can overwhelm and destroy sensitive electronic components, such as those found in musical instruments. Very often the first sign is that the power adapter itself is destroyed.
Therefore, it’s a good idea to protect your keyboard with a surge protector. Tripp Lite manufactures surge protectors that offer considerable protection and financial insurance. For instance, this device offers $10,000 in coverage in addition to the electrical protection it provides. That’s considerably more than the value of a Yamaha P115.
It’s also advisable to unplug electronic devices during thunderstorms. This mitigates against the risks of a power surge. It’s important to note that while surge protectors can handle minor fluctuations, they may not fully protect against the immense energy of a nearby lightning strike.
In conclusion, the damage observed in this instrument underscores the vulnerability of electronic devices to lightning-induced power surges. Taking proactive measures to protect such equipment is essential to prevent similar occurrences in the future.
Also, although this probably wasn’t the problem here… keep your beverages off of your keyboard! Spills remain the #1 source of trouble, even if power surges follow closely.
Yamaha GH actions require the insertion of a “rod” (as it’s referred to in the service manuals). Yamaha sells a specific tools—specifically part TX000671 (VCN03010) during disassembly. The rod blocks the hammers, relieving the pressure on the contacts and contact circuit boards. You can then easily remove the contact boards, or perform other service.
The Official, Correct, Boring Solution
You can purchase Yamaha’s official part VCN03010 (formerly TX000671). It is a steel dowel, of suitable length and diameter to conveniently fit between the hammers and the frame. It’s exactly as perfect a steel dowel as one would expect from Yamaha. However, it is nonetheless nothing more than a plain steel dowel.
Driveway markers are not only the correct size to fit nicely in both the Yamaha GH actions, blocking the hammers, but I find them easier to use. The marker slips more easily between the hammers and the frame because of its tapered, pointed end. It’s made of fiberglass, so it’s less likely to cause unintentionally scratches. And in fact, the far end even comes with a ready rubber bumper, just in case you lose track of it and whack a wall with it!
The TX000671 (VCN03010) currently costs $187.0 to the public on Yamaha 24×7, whereas the trusty 48-inch driveway marker costs $3.27 at Home Depot (prices as of 9/9/24). It’s an option worth considering! I now have a small stack of these in the corner of my shop, just in case I need one unexpectedly.
I’ve verified that this does, in fact, work on the newer GrandTouch actions, such as the GrandTouch-S in the CLP-745.
I recently encountered a Yamaha PSR-S750 with a couple of issues that appear to be quite common in this series. I wanted to share my experience in the hope that it might help someone in the future.
Sudden Shutdowns
The customer initially reported that the keyboard would display an error message at irregular intervals and then require a restart. This issue turned out to be related to a known problem with the main DM board. Apparently, early versions of this board have a tendency to delaminate, leading to errors such as the following:
“Unexpected error! Turn the power off and on again.”
However, the board can fail in various ways, including issues with powering on, sudden shutdowns, and more. The recommended solution is to replace the DM board (part #WZ353701). Unfortunately, this is not a cheap fix—the part currently costs around $503 on Full Compass (as of August 2024), though a Yamaha service provider may be able to offer it at a lower price.
Keyboard Turns On but Won’t Turn Off
This is an interesting issue. The power switch on this keyboard is a rubber button that, when depressed, completes a circuit to ground. Over time, as the button ages and the graphite on its underside degrades, it does continue to complete the circuit, but the resistance increases. Eventually, this high-resistance path is enough to signal the keyboard to turn on, but not enough to signal it to turn off. Diagnosing this issue can be tricky because the button consistently powers the keyboard on, even though it is the source of the problem.
The replacement button is part #WZ960401. Replacing it involves removing the entire front panel, making it a somewhat involved process. It would be wise to have a copy of the service manual on hand before attempting this repair.
Notably, the same issue can occur in the PSR-S770, PSR-S950, and PSR-S970.
Finally, make sure to update your Yamaha PSR-S750 to the latest firmware!Download the latest firmware file, put it on a USB stick, and insert the USB stick into your PSR-S750. Then Power On the keyboard while holding the Start/Stop button (below the LCD screen). You’ll be guided through the update.
I was working on a Roland KR-370 that had been through a lightning strike, and I was looking for the BIN file to program onto a replacement EPROM (IC2). I did eventually find one, posted by a very helpful individual in the Badcaps forum.
I recently had a client request I replace the stock GH3 action in her Yamaha CVP-305 with a Yamaha Natural Wood action, and I had an opportunity to do some experimenting.
The Yamaha GH3 keyboard action can be replaced with the NW-GH3 action, the GH3X action, or the NWX action. All four of the actions below seem to be interchangeable, with the features as listed:
Plastic
Wood
No Escapement
GH3
NW-GH3
Escapement
GH3X
NWX
Her favorite action was the NW-GH3. Although there’s some subjectivity, we mutually agreed that the natural wood actions were lighter than the plastic equivalents (which is a bit counter-intuitive initially), and that the escapement added perceived weight.
In other words, we found that the NW-GH3 action was the lightest action, perceptibly, and the GH3X was the heaviest.
I recently had a customer report their P105 was producing no sound, although occasionally, it emitted a scratchy noise. Attached to this post is a picture of the burned out chip I found inside the unit. The solution was a replacement DM board (Yamaha #ZJ257000).
I recommend customers with worn-out floppy disk drives upgrade them to “Floppy Disk Emulators.” There are a couple of these on the market. However, the easiest to install and use is the Nalbantov USB Floppy Disk Emulator. I install these regularly in Yamaha Disklaviers, but they can also be installed in keyboards. If you order from Nalbantov directly, make sure to use the AlexPiano for a 5% discount on orders from Nalbantov.
Why Upgrade?
There are several reasons why you might want to replace an old floppy disk drive with a USB floppy disk emulator, including:
Increased reliability: USB floppy disk emulators are more reliable than traditional floppy disk drives. They have no moving parts and are less susceptible to mechanical failure. Most customers reach out to me after their floppy disk drive has failed.
Compatibility & Convenience: USB floppy disk emulators are compatible with modern computers. Most of my customers no longer have floppy disk drives built-in into their computers!
Cost-effectiveness: USB floppy disk emulators are often more cost-effective than purchasing a new floppy disk drive or repairing an old one. Even if you can find a suitable floppy disk drive, compatible drives typically sell for hundreds of dollars! And then you have to purchase floppy disks, which are increasing difficult to obtain.
Operation
After the Nalbantov is installed, you can use a single USB stick to represent up to 1000 floppy disks. Because it’s a floppy disk emulator, the Disklavier actually believes you’re inserting a different floppy disk. As you switch between virtual “disks” by pressing the arrows, you’ll see the display on the Disklavier behave as though you’ve inserted a new disk. Of course, if you have more than 1000 floppy disks, you can invest in another USB stick, although I haven’t run into this particular situation yet!
This is the #2 track on the #27 floppy disk stored on that USB stick!
Installing the Nalbantov
Some customers opt to install the Nalbantov unit themselves. Depending on the design of Disklavier, this is quite doable, although I don’t recommend attempting it with most Yamaha MX100II Disklaviers (see below). It is a very easy installation on, for instance, the DKC5R and the DKC500RW, just to pick a couple of examples.
With some generations of Disklavier (most notably MX100II devices), the floppy disk drives are mounted behind a shaped plastic piece. In these cases, you’ll need to cut away the old plastic facing (a pair of flush-cut nippers is helpful here), install the new drive, and put some kind of buffer around it. I’ve experimented with a few different choices for something functional and attractive. Purchasing neoprene strips is a cheap solution.
New solution: I have a 3D model of a floppy bezel that’s sized to fit around a Nalbantov. You can 3D print this yourself, or I can mail you one. This mount holds the Nalbantov in place, and also fills in the gaps around the edges. It’s an all-in-one solution for mounting the Nalbantov, and allows you to reuse the same screws the original floppy disk drive was installed with.
My customized 3D-printed bezel in place over a Nalbantov.
For backing up your current Disklavier floppy disks to a format that can be stored on your USB stick, see my article on Backing up Disklavier Floppy Disks. They can then be moved onto a virtual “disk” with Nalbantov’s proprietary tool.
One or more keys play at full volume even though I’m hardly pressing them!
Keyboards use very sensitive contacts to determine how fast you’re pressing the key (or the velocity). A keyboard with dirty contacts (such as the one pictured below) will misjudge velocity, and will cause the key to play at incorrect or, often, persistently loud volume. In the case of the picture below, that wood chip would cause a perpetually quiet key—if it moved to the depression directly above it, then it would cause a perpetually loud key. Cleaning is sometimes an effective option.
They can also simply wear out. If you play your keyboard for hours a day, the rubber itself will eventually degrade, as will the graphite pads on the button. In that case, they’ll need to be completely replaced, which is typically possible for keyboards that are less than ten years old, but becomes progressively more difficult with age. Replacement is usually the best option.
In desperate times, if contacts just aren’t available, you can swap contact strips from the ends of the keyboards to replace keys you play more typically. There are products like Oak Tree Vintage’s Key Contact Repair Kit, but I view these as an absolute last resort. Direct rubber contact strip repair is a desperate measure.
Here are some typical keyboard contacts from a Yamaha Clavinova. There appears to be some kind of wood shaving in one of the contacts (toward the center of the image). This will cause misfiring.
One or more keys don’t play at all.
A common cause of silent keys are bad or damaged rubber key contacts. See above. They should be cleaned or replaced.
Another common cause of silent keys is a damaged or corroded key contact printed circuit board (PCB). These PCBs are, for late-model keyboards, typically available—particularly for Yamaha and Roland. They can also sometimes be repaired: In the case of the image below, some cleanup and a wire jumper fixed the problem.
If there’s sufficient corrosion on the contact circuit board, it will need replacement. In this case, I was able to add a wire jumper to bring life back to this particular board, and then coat the area to prevent further corrosion.
My keyboard doesn’t turn on!
There are many common reasons for this. The most common, in order, are damaged power cords or adapters, a blown fuse, a damaged power inlet (see below), or a damaged power switch. It can also be a sign of an electronics failure somewhere else in the keyboard.
Start by replacing the cord. That’s something fairly inexpensive you can do yourself. Try to find a direct manufacturer replacement. If you require any assistance in this, you can contact me, or you can reach out to a local piano store. In the case of a power cord with an adapter, both the voltage and the polarity have to be correct.
Somebody broke off the power inlet on the back of the keyboard.
This is a common problem. Nearly every pedal inlet for nearly every keyboard is available. I replace them regularly, particularly in schools where the cord might get forcefully pushed or pulled! Depending on the way that it was broken, there might be some collateral damage. For instance, a Roland I repaired recently had the fuse assembly ripped off when the power inlet, acting as a battering ram, scraped the electronics off the rest of the inlet circuit board. However, there’s nothing particularly complicated on there, and their story ends happily!
I’ve got a Yamaha Clavinova and some keys are sticking.
This is a very common issue in Yamaha Clavinovas from the early 2000s. Unfortunately, the tails of the keys would crack, resulting in sluggish behavior. Then they would fully break, causing a sticking key. More than once, I’ve gotten a call after a rowdy child will walk up to the keyboard and spontaneously break a dozen or so keys—it’s not their fault. These keys can be replaced.
I typically don’t recommend doing them one-by-one unless you’re going to be replacing them yourself. It’s much better to replace the entire keyboard assembly or to replace all the keys. This is an expensive repair, but it’s much less expensive than a brand new Clavinova, and if the rest of the electronics are in good shape, it’s worth considering.
I’ve got a Roland RD-xxx and one or more keys are staying down. They seem loose.
Roland RD keyboards from the 2000s and earlier used plastic hammers that crack and break. Unfortunately, Roland no longer manufactures these hammers. If you have such a keyboard, you’re at the mercy of used parts dealers and eBay. I maintain a small stockpile for customers, but this condition is usually terminal.
Cracking Roland hammers. All of these are splitting, both horizontally and vertically, around the encased lead weight. They are, unfortunately, irreplaceable.
I’ve got a Yamaha, and it makes a clacking sound when I let go of or hit a key.
Yamaha Clavinovas and portable keyboards have a strike felt and a rest felt. In nearly all cases, rest felts will wear out within a decade. This causes keys will make a clacking sound when released. With heavier use, strike felts can also wear out. Both felts are relatively easy to replace. Both lead to a noisy keyboard.
This is a worn out hammer strike felt on a Yamaha Clavinova. (It had, in fact, already peeled off when I opened the keyboard and was resting on the hammers.) The keyboard rest felt is toward the bottom of the keyboard assembly. It’s the piece the metal hammers are resting on.
In 2022, I had a customer ask me how to change the voltage on his Nord Electro 3 from North American to European. I made this brief write-up to help him.
This also includes how to replace the Electro 3’s fuse. If you’re a world traveler, this might be worth printing out and keeping in your bag—perhaps along with an extra fuse!
