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[DaveMusic8888]

Today I get a very loud snap sound near the plastic case above the key(F above middle C; and bit less the F#).
It's very loud and noticeable. It's from the physical back of the key or the plastic case; not from the synth output. No snap until you reach a certain high velocity striking; then every time at or above the velocity.

What can I do???

Thx,
Dave
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[19naia]

You can take it to service and repair location.

Or you can open the kronos yourself if you know how, or if you are bold enough to risk learning on your own. There are many past threads on the forum that talk about how to open up kronos safely.
Usually sounds like that in the key action, will be related to something being dislodged or broken off inside.
Sometimes you can hear the broken piece rolling around inside as you pick up the keyboard to turn it over.

I am not sure what the problem is, but opening the kronos outer body is the best way to get a look inside for finding the problem.
And since it is just one or two keys only, you can compare the inner parts and pieces of the good keys with the bad keys, so as to find what is different about the bad keys.
X-ray or other kind of remote imaging machines may not be as safe for kronos as taking out some screws and removing the base plate to look around inside.

[DaveMusic8888]

Thanks, I will try taking it apart to take a look!
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[geoelectro]

Sounds like the key weight felt is worn, possibly cut.

Geo
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[burningbusch]

It sounds like it could be the key hitting the front strip. Even if it looks like it's not, the problem can be in an area lower than what's visible. What you can try it this.

Disconnect everything and place the Kronos on its back (so the connectors are on the floor or bottom). Obviously, make sure the surface is soft and won't damage the back. Then, unloosen the eight large bolts on the underside of the Kronos. On the 73, there should be three on the row nearest the front and five on the middle row of bolts/screws. It is only necessary to loosen these large bolts as they are the ones that hold the keyboard in place. You don't have to loosen them much, only so that the keyboard is free and can shift. Gravity will move the keyboard away from the front strip in a uniform fashion. Finally, tighten those bolts again and try the keyboard. I have found this simple adjustment to fix the problem most of the time.

BTW, the main front panel and the front strip are brushed aluminum, not plastic. The area with the joystick and ribbon is plastic.

Busch.
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[DaveMusic8888]

Thanks, the 88 has 10 large bolts on the underside; 4 by front, 6 in middle.
I could feel the keybed moving down as I loosened the bolts as you described but
that didn't fix the problem which made sense since it only involve two keys; not the entire keyboard.

Once I had completely removed the under cover the problem was immediately visible.
As geoelectro thought; it was the key weight felt; not cut or worn but fallen down at that point.

There are two felt strips that go from F above middle C up and down from E below middle C.
I was able to carefully bend with needle nose pliers the fallen end up into place.
But now I need to figure out how to keep it there (and the end from E down is also starting to come loose).

Looks like the felt strip (sandwich of black top, white bottom) is glued down to a white strip above (behind) of an unknown material; might be pliable.

Should I put a drop of Elmer's glue on the strip?

Or does someone know the best way to re-attach this felt strip so it will function properly and not come off again???

Thx,
Dave
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[KK]

Do not use glue. Contact glue could work, but then you would have to remove the whole action, some keys and springs, etc. If you are talking about the stop felt for the metal weights, it is against metal (nothing pliable under). Instead use small parts of very thin double-sided tape. Press on a few minutes while gently massaging/moving the felt so it grips correctly.

The RH3 action is very well done with a quite small tolerance between felts and the aftertouch (AT) component on the other side (unless you have a recent model without AT). So anything too thick (1 mm is way too much) under the felt will compromise the AT efficiency for the keys under it.

[19naia]

Yes i would go with the idea of not using elmers glue.

If it is glue added to parts that contribute to the weight in weght action, Elmers glue is a heavy and thick glue that can close gaps that may be designed for a purpose, and also add weight if put on a weight balanced area for the weighted action perfection.

Super glue is the lightest and thinest glue i can think of and a tiny bit goes a long way as long as you are not messy about it and also quick.

You really do have to take seriously adding wieght to parts critical to weighted action calibration. And yes glue adds weight.

And as mentioned before, think about gaps as designed.
The wrong kind of glue could harden differently and cause a different kind of contact response where you get a different contact sound where the glue was applied.

So the glue idea has to be really thought through. The thinnest possible, and even then, the hardening of it could not match the factory adheseive and that can change the contact noise.
But i doubt the change in contact noise will be anything serious and would be a lot better than the original problem.
Emers glue is too thick and bulky. It would be bad for contact noise, gaps and weight balance if weight balance applies.

Only way i would agree with Elmers glue, is if Elmers glue or similar consistency was what the factory used.

The old adhesive is probably still there but not working, so remember you are adding to that in weight and gap filling.

The thinnest lightest glue possible is the best option.

[DaveMusic8888]

I did achieve a satisfactory fix. I only hear a slight difference in the bounce back sound after striking the F key.

I didn't go with super glue because it does harden so quickly and I needed to be able to apply glue to the white pliable AT strip at different points and be able to slide the sandwiched felt/foam strip onto that gradually as I worked along it. It had come loose for quite a way under many keys.

So a super light coat of Elmer's glue-all worked fine; hard to maneuver in that tight space; I used a narrow applicator.
My first attempt failed on the F+ side (worked on E and below cause very little problem there) because I didn't wait long enough for the glue to settle.
2nd attempt I waited over night before doing any playing.

As one of the first commenters noted; loosening the main bolts; the keyboard falls down a bit;
SO when re-assembling; the holes in the keyboard don't match up to the back plate.
I had to turn the synth onto it's front so gravity moved the keyboard back into place to get the holes to match up and install the bolts.

Thx,
Dave
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[DaveMusic8888]

A new problem resulted from putting the bottom back after my repair of the felt strip: the F below middle C was mechanically harder to press; particularly noticeable when pressing against the very back of the key. A Near by key had the same problem but less.
And it seemed as if the entire bed of keys was just a tiny bit harder to engage in particular at low velocity striking.
A few days later; the problem was most evident in the A below middle C and not so much for the F.

The fix was very easy and came from commentator burningbusch: I put the 88 on its back; loosened the 10 bolts holding the keyboard which allowed it to move down by gravity; then re-tightened the bolts.

In the previous post I mentioned having to install the bolts when the keyboard was set up on its front in order to get the holes lined up. If I have to remove/replace the entire bottom again; after getting the bolts into their holes; I'll put it on its back and loosen and then retighten the bolts to prevent a reoccurrence of the stiff action keys
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