Williams Encore Digital Piano

Sold by Guitar Center. Unit power up but is mute. Possible firmware issue? Possible bad solder joint? Anyone have a schematic or service manual to reset firmware? Other servicing hints? Thank you.

What is not working?

Speaker Output? Headphone output? Line outputs? MIDI output?

Some or all the above?

Gareth.

Intermittently, panel lights but all of the above fail. Williams lists reset squences for some models, not the Encore. Trial and error got me into "test mode" by powering and and pressing both transpose keys. Sound restored. So I am thinking this might be a firmware issue rather than a bad solder joint. If this fails again, I was looking for further guidance. I assume there might be a "restore" sequence but Williams customer service was mum.

Intermittently, panel lights but all of the above fail. Williams lists reset squences for some models, not the Encore. Trial and error got me into "test mode" by powering and and pressing both transpose keys. Sound restored. So I am thinking this might be a firmware issue rather than a bad solder joint. If this fails again, I was looking for further guidance. I assume there might be a "restore" sequence but Williams customer service was mum.

It sounds more like a Power Supply problem to me.

Are you using the power supply originally supplied with the keyboard?

Gareth

I have 2: the original and a replacement. 12V 4 amps. Both show good under load. [Owner had thought power supply could be the issue, also.]

I have 2: the original and a replacement. 12V 4 amps. Both show good under load. [Owner had thought power supply could be the issue, also.]

I have 2: the original and a replacement. 12V 4 amps. Both show good under load. [Owner had thought power supply could be the issue, also.]

Most likely suspects in order of likelyness:

Dry joint on, or damage to, DC input socket. (Usually confirmable by wiggling it) Dry joints on other component parts of the power supply regulation circuit. Damaged components/PCB traces due to incorrect polarity PSU being used.

Least likely suspect is firmware or anything computational.

Gareth.

Thanks. I will plod along further.

Not the power supply, I think. Unit plays fine for hours. Then goes mute. Powering up into test mode restores sound. So far everytime. The reboot and plays fine again for a long while. If it stays this way, only an irritation but I'd welcome any more hints.

Nevertheless, you normally have to start by looking at the power supply, not just raw voltage but often "quality" as well.

Example: ripple, oscillation etc.

Let's suppose a crappy 10uF capacitor at the output of a +12V regulator causes it to break into oscillation, but rebooting in test mode draws a bit more current and kills the oscillation temporarily.

Restart, runs a bit longer, breaks into oscillation again.

Your only clue using a simple multimeter might appear to be a low DC voltage, perhaps, but no clue about the oscillation without a 'scope.

All I'm really suggesting though is don't exclude the power supply - keep your mind open.

Mark Z.

If it has a Rom or Eprom and is more than 10 - 20 years old, you might have a firmware problem with bit rot.

tm

Yes, so far test mode has been a reliable fix. Everytime.

Ah. Interesting and way beyond my ability to fix. :)

No scope available but I will keep this in mind. Thank you all.

Yes, so far test mode has been a reliable fix. Everytime.

That's a pretty unusual set of circumstances. (Do you know if it has a memory backup battery? If so, can you measure it to see if it is good or bad?)

Well, if the fault is cleared by going into Test Mode but not cleared by a normal boot, that pretty much excludes everything except the mainboard/firmware, and possibly backup battery, though that's a long shot.

Gareth.

Oh, I have just thought of one more thing:

It might be possible that one of the front panel switches could be faulty, in that it is permanently or temporarily held on. This means the keyboard boots up with one or more switches depressed, and/or operates with this switch permanently or temporarily depressed.

This is often a useful tactic to use - booting into Test Mode for example, but sometimes might prevent the keyboard from booting properly, or possibly corrupt the system when it does, if the firmware programming is not robust enough to deal with such unexpected events.

My gut feeling though is you have a Flash Memory problem or dry joints on the Mainboard.

Gareth.

Yes, odd but seemingly reliable was to restore. I think I am agreeing with you about the mainboard or battery backup.. I have not determined how to nondestructively get to the mainboard to see if there is a backup battery. If anyone has actual experience with this kepboard, any direct advice on how to disassemble would be appreciated. Thank you.