RD700 - Some Keys Quiet - Wear or Software Issue?

[4n6days]

I have a RD-700 that G4 and G5 will not play loud. No matter how hard you play those keys, they're very quiet. All other keys seem fine.

Has anyone else run into this? If it is wear, what is worn?

-Chris

 

[happyrat1]

There are two electrical contacts for each key on a velocity sensitive keyboard. One registers the top of the keystroke and the second registers the bottom of the stroke. The duration of the pulse between these two signals determines the velocity or loudness of the strike.

Usually this type of problem is caused by dirt or crud fouling one of the contacts or could be wear as well.

No way to really know without opening it up and doing some cleaning and visual inspection of the situation.

If you don't know what you are doing I do not recommend this as a DIY job.

If you're handy with disassembly of complex electro mechanical devices I'd advise checking out a few youtube repair videos and taking a series of still photos or a cam video of the disassembly so you know how to put it back together again.

Otherwise, take it to a tech and pay a couple of hundred for a fix.

Unless it's under warranty still. Then milk that puppy for all it's worth

Gary

 

[4n6days]

Gary,

Thanks for the response. Much appreciated!

I did see some repair kits that included a conducive coating to repair worn contacts, but I couldn't figure out how that measured velocity, thanks for explaining that. If the contacts are worn, is recoating them a viable repair?

-Chris

 

[happyrat1]

More likely than worn contacts it's probably just some schmutz under the contact.

If it's a case where the silicone boot of the contact is worn those kits might be a fix.

Then again, it could also be a break in the boot as well.

How old is the keyboard in question and how often is it played on a regular basis?

Gary

 

[happyrat1]

These are better repair kits for keyboards.

However, it is usually highly unlikely you'd use them unless the keyboard is positively ancient.

Like I said earlier, the problem is probably just dirty contacts.

And if a contact strip is damaged, that would necessitate the purchase of a replacement part.

Again I ask how old is the Keyboard? Roland's been making the RD-700 series for a very long time.

Gary

 

[4n6days]

I'm not sure of the age. I think it's in 10-15yr old range. It belongs to a church that used it 2-3 days a week for several years and then replaced, presumably because of the velocity issue.

 

[happyrat1]

If it's less than 20 years old chances are the contact strip is not damaged. Probably just needs a cleaning.

Gary

 

[4n6days]

Well... just found out it was bought used. Guess I'll just have to open 'er up and see what we can see!

 

[happyrat1]

Don't forget to use a camera and document what you take apart so you can put it back together again.

And check out some youtube videos on keyboard repair first so you know what to expect inside.

Good luck

Gary

 

[happyrat1]

BTW to clean these contacts use denatured 90% alcohol.

Gary

 

[Biggles]

Additionally at Radio Shack or similar you can buy aerosol cans of compressed air, if you open up the keyboard a quick blast of air can move dust and grit prior to using the cleaner Gary refers to.

The Sales folks there will probably try to sell you a can of contact cleaner, I would suggest you avoid an aerosol can as the resultant spray can get everywhere and as some contain a lubricant which in the future the residue lubricant can act as a dirt magnet.

 

[4n6days]

I took it apart and cleaned the G4 sensor and tried it and... it works!! For some reason, I didn't do the G3 sensor at first, so I had to take it back apart and clean that one. It's all back together and working great!! Thanks for your guidance!

-Chris

 

[happyrat1]

Congrats!!! Happy happy joy joy!!!

Glad nothing else f***ed up.

Enjoy making music again.

Gary

 

[4n6days]

I made a video of my repair. One thing I left out is that I did color lightly with a pencil on the conductive rubber pads. Not sure whether it was the alcohol or the graphite or both that ultimately solved the problem.

 

[happyrat1]

Congrats! The video was nicely done.

I'm happy you succeeded in the fix.

You just saved yourself $200 to $300 in service costs

Gary

 

[Rayblewit]

Wel done on the repair. Thanks for sharing the vid. Most intriguing. Cheers
Ray

 

[Daniel in Berlin]

I made a video of my repair. One thing I left out is that I did color lightly with a pencil on the conductive rubber pads. Not sure whether it was the alcohol or the graphite or both that ultimately solved the problem.

I am grateful for your video. Thanks! I followed it. Cleaned the one pad that went bad. Now when i put it back together, all the keys have the same problem (you have to pound them to get any sound and there is no dynamics). Any ideas?

 

[happyrat1]

Possibly you inverted the pads when replacing them. That would disable the velocity sensitivity.

Gary