Question about Yamaha Music
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
Here's a link to this great service
Posted on Jan 02, 2017
There are flexible cables that connect the keys to the main electronics. The connectors for those cables sometimes age poorly..
It is fixable. But dont "get taken" on a repair.
If it's just resoldering a few points,it shouldnt be more than $100.00
Posted on Jan 12, 2009
Either the first or second closure matrix line for the "A" keys is bad.
This may be a cracked or shorted circuit board.
A bank of diodes is used to prevent sneak electrical path if more than one octave has notes pressed.
First thing is to clean ALL the key contact areas and the conductive rubber pills with 99% isoprophyl alcohol.
This involves dis-assembly of the key area. If you are not competent in electronics, best left to a pro shop.
The keys are scanned in a matrix, two contacts per key and all the individual notes are in common (all the "A;s", "B's"...) And each octave is strobed for the first set of contacts and then for the second set of contacts. an the whole octave is read in parallel.
The reason for two contacts is one closes first and then the other as a key is lowered. The time between these is measured and is the note VELOCITY which for a piano controls the loadness of the note. IF ONE of the two fail, the loudness will vary as yours does.
Posted on Nov 27, 2009
The key switches are scanned as a matrix. One of the matrix wires has broken or connector/cable is not making it... It will be a connection in common with the non-working keys.
Here is schematic:
On page 40 on the board labelled 61H-MK and the connector DMLCD-CN401 the connections to pins 11 and 12 with signal names N14 and N24 have become broken or disconnected before they get to the processor board.
Since these lines are NEAR an edge, the cable could be not quite in the connector at one end or the other. These two wires are what triggers the E and the A# key signals. There are TWO contacts per key as one closes first then the other... this is how they measure key velocity.
Posted on Jan 17, 2011
Testimonial: "Thank you so much. You saved a good keyboard from going to a landfill! It was easy to fix with your information."
under the keyboard there is a switch for each key, try to clean it whit water and a smooth paper.
I have Roland keyboards and it happens after playing a lot.
Posted on Feb 07, 2011
Testimonial: "Thanks for the info. I will give this a try and hope that this solves the problem."
Tips for a great answer:
Apr 03, 2014 | Yamaha DGX640 Music Keyboard
Jan 28, 2013 | Yamaha Music
Sep 06, 2012 | Yamaha P95 Digital Piano
Aug 17, 2011 | Yamaha Music
Apr 25, 2011 | Yamaha P85 88Key Portable Digital Piano
Feb 11, 2011 | Yamaha 5C Standard Bb Bass Clarinet...
Feb 07, 2011 | Yamaha Portable Keyboard
Dec 20, 2010 | Yamaha Full-Size Keyboard
Jan 01, 2018 | Yamaha Full-Size Keyboard
150 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: