Piano World Home Page Forums Our Most Popular Forums Digital Pianos - Electronic Pianos - Synths & Keyboards A spill story / did anyone here have the Roland HP 1700?

Hi everyone,

I'm new to PianoWorld - hello! For the many years I have had a trusty Roland HP 1700 digital piano. It's been incredibly reliable and has a wonderful sound, but after an unfortunate recent spill, I think I may have wrecked part of the circuit board inside (the 10 keys directly below middle C now play at full volume all of the time). My question is two-fold:

1) Has anyone dealt with a spill situation like that and actually fixed it?
2) Did anyone here have the HP 1700 and replace it with something similar? And if so, what did you choose?

I know there are many questions asked here every day, but I would be so grateful for any advice!

Most pianos have a membrane with rubber-dome buttons under each key. Each key presses a button (actually two or three buttons) to actuate the sound. The spill may have left residue under those rubber domes. The repair might be as simple as cleaning up the circuit board and the rubber membrane. This requires a bit of skill and patience.

+1 to Mac, sounds like a liquid, or residue, short circuit of the key contacts. I would not put power on it again, until it's dried out and you've opened it up and started cleaning all traces, including under the key contacts.

Yep, corrected this many times. It requires you to get gutsy about taking it apart (take photos, label things, or take it somewhere if you're not comfortable) but otherwise have at it. The rubber membranes pull off the circuit boards (they are held on by rubber studs that poke through holes) and you can use a Q-tip to clean the circuit board and the membranes, which should come off in strips almost an octave long. I've used rubbing alcohol, but you may want to try to find something more pure. Don't be afraid to really douse that alcohol on there. It won't hurt it as long as you don't leave it wet. But being alcohol, it'll evaporate before your eyes.

Get it all clean, dry it out well and put it back together.

Don't rub on the carbon contacts too hard (both on the membrane and on the board). They're delicate and can be damaged.

Hey - thank you so much for the replies everyone! I took it apart and found the rubber membranes - I used an electrical contact cleaner + lubricant on them (from a local electronics store) and put it back together...unfortunately, after I did, even more keys were suddenly too loud! Like, all of the keys I removed to fix are now too loud. Not sure what I did wrong - I'm afraid that maybe getting the cleaner with lubricant was a mistake? In any case, I'm willing to give it another shot - maybe this time with rubbing alcohol.

Thank you again! Any further advice would be greatly appreciated if you have it.

No lubricant!

Keep it level at all times until it dries, if at all possible.

Surplus liquid will run around inside and may make the situation worse.

+1

The cleaner you use must evaporate and leave no residue at all. Many have an oily base which leaves a thin almost unnoticed film. 100% pure alcohol is good

Yeah, what's most likely happening is that the lubricant is shorting the contacts. Since there are no parts of the electronic assembly that need to be lubricated, they are best left bone dry. The alcohol should take care of that. Keep us posted!


As you saw when you were in there, there are two contacts per key. Due to their positioning and the length of the buttons under the membranes, one contact will always be tripped first when operating correctly. What the piano's processor does is measure the amount of time between both contacts being struck to determine the velocity - and subsequently, the final volume. When those contacts are shorted (from dirt, liquids, etc), both contacts are tripped simultaneously, resulting in the processor reading it as FFF.

Thank you again everyone! I know there are so many posts here every day and tremendously appreciate the help resuscitating my poor keyboard. I took apart the keyboard again and cleaned it again with an electronics cleaner without lubricant. Bone dry!

...then I realized that I had put the rubber strip in backwards last time. Real smart!

Anyways, after all the cleaning, the section where the spill happened is all fixed! Presto magic. And I also managed to fix a key that the spring had sprung out of.

A low F has had the "loud" problem for years, and despite my best cleaning efforts, that hasn't been fixed. Oh well. Any ideas?

Also: I lost the pedal for this HP 1700 a while back in a move - anybody know where I might be able to get a new one? Roland doesn't carry them anymore.

Thanks, all!!

Glad to hear it's mostly working again.

Does the loud key send a velocity of 127 (maximum) every time it's played? If so, it's possible that the rubber could be torn. I saw a youtube video of a guy swapping the rubber from an unused key (like the very highest note in the piano) for the torn one. It was pretty major surgery and involved some risk but it worked for him and if that key is driving you bonkers, it might be worth it for you.

Haha, I actually tried something like that. Unfortunately even with the new rubber (from the highest octave - I just switched the whole octave to avoid cutting) it's still loud. I suspect it's the circuit board. Not the end of the world, and not an extremely frequently used key.

Thanks for the tip.

Dear All,

I recently joined the forum after I googled your post.

I own the same piano. I bought it in the Netherland 20 years ago at least, the voltage is there 220V. I moved to the Caribbean and the voltage is there (St. Martin 120 V 60 Hz) I used it with a converter, no problem. Then I moved to Curacao where the Voltage is 110V 50HZ, so while using teh same converter oen day many years ago it just stopped. I approached many local hacks, but no one had an answer. I suppose it soemthing simple electrical. Can any of you guys guide me inthe right direction?

I would really appreciate this.

Jean

Are you electrically minded or have some training?

First check, change the fuse in the power lead or block, if there is one, or try a different lead/block. Second, if so minded, open it up and look for an internal fuse. Third would be get the multimeter out. Fourth, or first if no electrical training would be take it to a service center.