Hello everyone,
I have a Yamaha P-95 that after approximately one year of being stored, currently is not emmiting any sound from either speakers or headphone plugs.
I checked the functionality of the Keyboard and the MIDI processing was ok. I tried all the quick solutions out there (enabling internal audio, check if something is blocking the headphone plugs, cleaned volume key), I figured it had to be the amp board so I decided to open it and see if there was a component with blackened leads, or some visual clue of the problem, but unluckily the problem wasn't so evident and there were no faulty components to be seen.
Looking for schematics I came across a post in this forum that stated a similar problem:
https://forum.allaboutcircuits.com/threads/speaker-relay-on-yamaha-r-90-receiver-not-closing.77234/
In wich it states that the keyboard has a protection circuitry that closes the speaker feed relay if after a few seconds from turning on the output stage is found healthy. This is indeed the case as I can hear the relay closing, and even opening again each time I connect headphones on either plug.
The strange part is that, trying to troubleshoot the situation, I unplugged the headphones board and after reconnecting it, the problem went away... unitl I turned the keyboard off and on.
Sadly the service manual has no schematics of any board. It only shows the disassembly of the unit.
Any thoughts on what may be the problem?
Thanks for reading,
German.
I have a Yamaha P-95 that after approximately one year of being stored, currently is not emmiting any sound from either speakers or headphone plugs.
I checked the functionality of the Keyboard and the MIDI processing was ok. I tried all the quick solutions out there (enabling internal audio, check if something is blocking the headphone plugs, cleaned volume key), I figured it had to be the amp board so I decided to open it and see if there was a component with blackened leads, or some visual clue of the problem, but unluckily the problem wasn't so evident and there were no faulty components to be seen.
Looking for schematics I came across a post in this forum that stated a similar problem:
https://forum.allaboutcircuits.com/threads/speaker-relay-on-yamaha-r-90-receiver-not-closing.77234/
In wich it states that the keyboard has a protection circuitry that closes the speaker feed relay if after a few seconds from turning on the output stage is found healthy. This is indeed the case as I can hear the relay closing, and even opening again each time I connect headphones on either plug.
The strange part is that, trying to troubleshoot the situation, I unplugged the headphones board and after reconnecting it, the problem went away... unitl I turned the keyboard off and on.
Sadly the service manual has no schematics of any board. It only shows the disassembly of the unit.
Any thoughts on what may be the problem?
Thanks for reading,
German.