CVP-900 Guide Light Problem

[barrett_flansburg]

I've had a problem with the guide lights on my CVP-900 ever since I bought it 6 months ago. When I first turn it on and try playing one of the built-in songs using the guide lights in guide mode, the piano will fail to detect that the correct key has been pressed a large percentage of the time. As I continue playing, pressing many keys two or more times before the piano detects the key press, the piano gradually gets better at detecting the key presses. So, after a few minutes it detects the key presses pretty reliably. It is as though the piano has to warm up before it works reliably. This behavior happens in both "Next" and "Just" guide light modes. Needless to say, this takes all the fun out of using the guide lights.

It is not just a subtle timing or touch problem becuase if I wait until a light is on and then very deliberately mash the key all the way down until it bottoms out the light will still remain on as though I never pressed the key. Of course, the piano must know that the keys are being pressed because it plays the notes for the keys I press.

I would appreciate any suggestions as to what might be wrong or if someone else can try duplicating the problem on his CVP. I will contact my dealer to get a technician out to repair it under warranty.

Barry Flansburg
Atlanta, Georgia

[mdoyle]

It does sound like a fault - do any of the voices sound softer than you'd expect (I am thinking that there's something interfering with the mechanical keypressing, so that would make all notes appear softer as they'd not travel fully..).

And of course, an obvious question, but you are not trying to use Guide with the auto accompanyment or any other auto features are you...

Does this occur with the Yamaha preset disk or just with others that you are loading in...

Regards
Mike

[wally]

I experienced a similar problem with a particular midi file some time back. When I viewed the file in CakeWalk, I found a shadow note -- the same note twice in the same place. The score display on the CVP wasn't able to show it. I deleted one of the notes and solved the problem.

Similarly, if you have two channels selected and the same note appears at the same time on each channel, I wonder if that would cause this problem.

Just some thoughts.

[Midi Magic]

Hi

Do ALL of the built in songs do this?
Make sure the guide lights are pointing to the right part, the one you are playing.

Midi Magic

[barrett_flansburg]

Yesterday the Yamaha repairman came out and fixed my CVP-900 under warranty. He replaced the main board (buried deep under the lid) and the guide light problem was solved. He said Yamaha knew about the problem and knew that replacing the main board would fix it. I suspect that the replacement main board is a later revision and that probably all CVP-900s with the original main board have the same guide light problem.

The problem was that in guide mode the lights would not go out and let you continue until you pressed the lighted keys a second time. The workaround I came up with was to press down every key immediately after turning on the piano; then the guide lights would work correctly.

I suspect this problem exists in all of the CVP-900s manufactured before the main board was revised, so it would be wise to check your CVP-900 for the problem and get it fixed under warranty while there is still time.

Thanks to all for the replies which helped track down the problem.

Barry Flansburg
Atlanta, Georgia

[jjm542]

My CVP900 had the same problem and Yamaha came to fix it today. It does require replacing a circuit board. According to the document that came with the new board, the serial numbers affected are 601001-601358. If your 900 is in this range, check to see if you have the bug and if so, get it repaired before the warranty expires. In the process of watching the repair, I learned how to take the piano apart, useful if a fuse ever blows (there are several of them, all inside the piano.)