EO9 Roland Problem Please Help

[edwine]

My keyboard has developed a noise problem after being in a cool / cold storage area for a year. all notes are sounding perfect, but when any key is struck along with the note is an almost static noise which is almost as loud as the note, equally in both speakers. lower volume not audible but louder volume strike any key hard is very audible. no noise at all when sitting static. So far I have only checked the boards for cold solder joints ect. . can not find a schematic don't know where to start. I am not a
qualified technician but I have repaired a lot of musical items in last 50 years any help would be appreciated thanks .

 

[happyrat1]

Sounds like dirty volume pots to me.

Buy some Canned Contact Cleaner and give the controls a good shpritz. Then work the controls back and forth a dozen times.

That should clean up the crackle.

 

[edwine]

thanks that's a starting place my first thought was volume control because that is central to all signals only reason I discounted that, is when rotating control when turned on it is quiet as a new control, but I will clean it anyway see what happens very hard to access

 

[Gourockian]

Here's a link to the E09 Service Manual which contains circuit diagrams. I hope you manage to clear up the static. https://www.manualslib.com/manual/1331121/Roland-E-09.html

 

[edwine]

thank you

 

[edwine]

Well finely had time to do some more investigation on keyboard, with no solution as yet. found one suspect cold solder joint on board which I resoldered, so that was not a problem, the volume control is as quiet as a new one but sprayed it with cleaner anyway, changed out both speakers with 4 ohm temporary speakers same problem. I found that when headphones are used in phone jack (speakers are cut out) the crackle noise is completely gone in headphones. I suspect a component in main board in "speaker circuit only", even if i could trace on diagram, which is not very clear to read, likely would not be able to get component any way. Maybe someone has had this problem I will wait for a while, if not, I will see if someone is parting out one in classified, maybe I can find a used board easier. thanks

 

[Gourockian]

I checked out the service manual I had sent the link for and sure enough, it is not too easy to read the circuit diagrams. Here is a link to a better quality scan. The site refers to it as a Roland E9 but when you download the service manual, it is definitely for the E09. https://www.synthxl.com/roland-e-9/

If the noise disappears when you use headphones, it may be that the contacts which are normally closed when the jack is not is use, are dirty. Spray them with contact cleaner and insert any old jack plug into it a number of times, while turning it. Better still, if you can access the jack internally, you might be able to physically clean the contacts using light emory /sand paper.

If that does not help, can you connect an amp to the two output sockets and see if the crackling is present. If not, you might be able to use the schematics to pinpoint the source of the trouble.

 

[edwine]

thank you very clear diagrams