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Hello friends, I have a problem with one key which is consistently too loud, It acts as if Im hitting it harder and quicker than I actually am.
I have seen the good work here where friends have opened up the DPs and exposed the internal workings. Is there a roland site where parts could be ordered from?
Has anyone had this happen ?

Thanks for reading this .

I have a key that is quieter than the others on my Kawai. I opened it up and looked for visible problems or obvious ways to adjust it but didn't find any. It looks just like every other key. There is one screw I can adjust that changes the height at which the hammer engages but I'm not sure it's the right thing so for now I'm living with it.

Having said that, if your key is actually outputting velocity 127 it means the rubber part of the sensor needs replacing. On the cheap you can steal one from a note you never play, like the top one on the piano.

Actually, this might fix your current problem as well, but I can't be sure. There is some slight risk in the procedure and you have to be kind of handy.

Mike, is it an original (early '90s) RD-300 or the recent/current RD-300GX/NX? If an original one I think you might struggle getting Roland to help. Someone out there will be able to help you - but probably not Roland.

Good luck,

Steve

Thanks for thr replies, its a 300 gx. I agree its most likley the contact point, however just wondering if anyone has attempted a repair/ replacement of this part?

thank you friends.

Hi,

I had this same problem at an F key of my 14 year Orla DP. The key played as if full strength was always applied. I suspect the problem with yours may be the same I had and as gvfarns mentioned the contacts that are used to "sense" the speed at which the key was pressed may be dirty and need some cleaning.
I'm posting the pictures of the disassembly on my Orla on this thread, but since I haven't yet had the time to post the keyboard pics to the thread yet, I'll leave one here(this was on my Orla so it might be slightly different on yours):



The photo shows the rubbers removed and all I did was clean the carbon contacts softly with a little alcohol on a cotton swab. If you try to fix it bear in mind it may or may not be an easy operation, depending on how the action of your DP is arranged. Also be sure to do it gently so you won't rip apart a contact

Hope this may be of some help.

Best of luck,

Tiago

Thanks Tiagor, yes, i think thats it, good picture.
The pics in the DP exposed section in this forum show a similar contact board in the rd300gx.
Does anyone know if the rubber component runs under all the keys or is sectional?

Cheers

As you can see, you can't simply steal a contact from an upper note as the PCB is one (or two) long pieces. The rubber component is usually sectioned and can peel off in ~octave increments (though they don't necessarily follow the pattern). Be sure to clean the rubber contact underneath AND the carbon on the PCB, but do so lightly.

The rubber switches generally attach to the PCB using little rubber studs that fir through holes. Peeling them out is easy, but you may want to have a toothpick handy for getting them back in.

Gvfarns - you may have lost the high velocity contact. Seems like people usually lose the low contact first, causing the highest contact to be the only one trigger, sending a 127 velocity reading (it assumes that the lowest contact was already tripped). This may be because the low contact gets used more or pressed harder -- who knows, but I have seen quiet keys, and I think it's basically the same problem. You usually can't see it with the naked eye. You've just gotta clean it up and hope it works (I'd clean all the contacts since you're in there).

If I had lost the second contact, no audible note would be produced (or maybe velocity=0). In my case the velocity produced is maybe 10% lower than expected whether I play loudly or softly. If you just played my piano for 5 minutes you most likely would not notice, but if you are practicing, trying to get scales even, etc. you will notice it.

It's definitely true that you can't easily just take one rubber thing and move it because they are indeed attached (many of them are), however, the person I know who did that cut their rubber strip and moved the good rubber thing down from the top key. YMMV.

Thank you, that makes a lot of sense.
regarding cleaning the contact points? Im assuming we are dealing with graphite on one side copper on the other.

Cheers.

I'm not sure what the material is in the contacts. I'm thinking maybe graphite and/or carbon? There isn't any copper - both the contacts in the rubber strip and on the circuit board are black.

You probably have carbon on both the silicone buttons and the pcb contacts. Carbon is an electrical conductor so each time you press a key it will short the two small strips of the pcb contacts.
When a contact stops working it has probably either stopped making contact because of leaking silicone oil or the carbon has worn out. In the former all you have to do is carefuly clean it. If the later happened (wear on the carbon attached to the silicone buttons) you can also try to fix it glueing a small and thin aluminum circle to where the carbon should be (being careful to keep approximately the samy thickness as the original carbon was.

Or get some of this stuff:



It's a carbon based paint that you paint onto the worn out carbon pads. I've used it to fix old remote controls. Makes them good as new.

Thanks for the valuable info, yes carbon to carbon thats it.
Im wondering now if one of the contacts on the board is dirty to the point that it allowing some current flow without the key even being depressed.
What compound, cleaner can be used safetly on the carbon points, just want to have everthing on hand before I go in.

Cheers

@Ando: That seems perfect. Didn't know that was available and sure is a better way to fix any wear, unless you want to improve de conductivity where aluminum would be best (can't see why that would be preferable for a DP though).

@Mikecanada: I can't see that happening without the key being depressed unless there is some scrap metal shorting the pcb contacts. For cleaning I'd go with some alcohol as it evaporates rather quickly and dissolves the silicone grease. Just don't use any solvent or the contacts will be history. I'm sure there may be more expensive options though but bear in mind all you want to do is clean the grease

For completeness sake, this is how the carbon in the silicone buttons look like. Be sure to clean these and the ones at the PCB too.

i have the same piano in 76 key form. I've taken it a part a few times. last time I had a key that was too soft. I just the key out and the cleaned the contact, etc. You can take a few out and test just by tapping the contact to see if you got the problem fixed. You could also try swapping the same key on the board with another of same letter. They are all weighted the same.