Disklavier

I wondered if someone could help with this?

 

I get quite a buzzing from under the keys on my Mk3 Disklavier. I have
stripped it down before and the cause is clearly the circuit boards below
the keys. However, I am reluctant to simply tighten them without knowing
what torque they should be tightened to. Or an idea of how tight I should
go. The screws are on springs if memory serves.

 

Thanks

Kevin

Exactly, where do you put the credit card?  Does it always stop the buzz?

Have you checked thoroughly for a foreign object?  Is there something sitting at the back of the bottom of the piano?  Is the front knee board tight?

I know this can be awful, but I have never encountered a loose board on the electronics.  Always, it is part of the piano.

Carol Beigel

Could it be caused by vibration from the hard disk drive.

 

Kind regards

 

Geoff Ward

From: disklavier@yahoogroups.com [mailto:disklavier@yahoogroups.com] 
Sent: Monday, 5 August 2019 5:14 AM
To: disklavier@yahoogroups.com
Subject: [disklavier] Re: buzzing noise from under the keys

 

  

Just trying to 'bump' this issue a little...

 

I can't believe it's just me that's encountered this  - a buzzing noise from under the keys on my Disklavier Mk 3 upright? It's driving me crazy!

 

I can temporarily deal with it by inserting a credit card between the keys - suggesting it is coming from one or two of the small circuit boards under the keys. But how to deal with it permanently? I have tried just tightening up the screws, but I don't want to overtighten them because I don't want to damage the boards

 

Thanks
Kevin

Thank you for getting back to me Carol
I put the credit card towards the mid to top range of keys. Under the keys are a couple of credit-card sized circuit-boards (with various chips and resistors soldered into them). What I manage to do with the credit card is simple make contact with the circuit-board under the keys and this stops the buzzing noise - even once the credit card is removed - but only temporarily. It always returns.
After stripping down the keys I found that each of the circuit boards is screwed down by four screws - which can of course be tightened. My problem is that I don't want to over-tighten these and end up destroying the circuit board. I'm also not sure whether there is more to it than this?
I'm surprised no one else has encountered this issue. It is the only problem I have with the piano which is otherwise great. 
ThanksKevin

Hi Kevin,

I currently have a Yamaha GranTouch GT1 which I am happy with.

Years ago I had a Glubransen Organ Model G-3.

When it was turned on in standby or I would play it, it would buzz too.

What I discovered is that some of the components, i.e. condensers, 
capacitors,
etc. where physically touching the circuit boards and actually causing 
the buzz.

If possible, get under the keys and get one of your ears to scan all over
the circuit boards while the piano is on to see if you can actually hear
where the buzzes are coming from as you pass by each component.

Then with the power off, I gently and very carefully, lifted where
possible, offending components slightly away from the circuit
boards or wrapped them with felt

When I powered the organ back on the buzz was gone and the organ played 
well.

If there are still a few buzzes, then revisit where the buzzes are coming
from with your ear and lift the offending component(s) a little bit more
or apply or reposition the felt.

Of course, resistors and some components, unless they have long enough 
leads,
you don't want to try to lift them up off the circuit boards as they 
will break.

Unless the screws are very lose on the circuit boards, I don't
think over tightening them is going to solve the buzz problem.

I can't tell if you have a similar situation here or
advise you to try what I tried, it's just a thought.

DNA

Portland, Maine, USA


On 8/6/2019 5:06 PM, Kevin Farnsworth evkinfarns@... 
[disklavier] wrote:
> Thank you for getting back to me Carol
>
> I put the credit card towards the mid to top range of keys. Under the 
> keys are a couple of credit-card sized circuit-boards (with various 
> chips and resistors soldered into them). What I manage to do with the 
> credit card is simple make contact with the circuit-board under the 
> keys and this stops the buzzing noise - even once the credit card is 
> removed - but only temporarily. It always returns.
>
> After stripping down the keys I found that each of the circuit boards 
> is screwed down by four screws - which can of course be tightened. My 
> problem is that I don't want to over-tighten these and end up 
> destroying the circuit board. I'm also not sure whether there is more 
> to it than this?
>
> I'm surprised no one else has encountered this issue. It is the only 
> problem I have with the piano which is otherwise great.
>
> Thanks
> Kevin
> 



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Following-on from this, I had another look under the keys today. Taking the keys off reveals a metal raised plate – 2-3 inches wide and spanning the length of the keyboard. It is mounted on ‘spring tensions screws’ (not sure of the correct term). I have tightened them a little and this seems to have fixed the buzz for now – but any suggestions on how much these screws should be tightened/loosened? 

 

Kevin

From: Kevin Farnsworth <evkinfarns@...> 
Sent: 06 August 2019 22:06
To: disklavier@yahoogroups.com
Subject: Re: [disklavier] Re: buzzing noise from under the keys

 

Thank you for getting back to me Carol

 

I put the credit card towards the mid to top range of keys. Under the keys are a couple of credit-card sized circuit-boards (with various chips and resistors soldered into them). What I manage to do with the credit card is simple make contact with the circuit-board under the keys and this stops the buzzing noise - even once the credit card is removed - but only temporarily. It always returns.

 

After stripping down the keys I found that each of the circuit boards is screwed down by four screws - which can of course be tightened. My problem is that I don't want to over-tighten these and end up destroying the circuit board. I'm also not sure whether there is more to it than this?

 

I'm surprised no one else has encountered this issue. It is the only problem I have with the piano which is otherwise great. 

 

Thanks

Kevin