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Old 31st December 2017
Here for the gear

Korg DW 8000 Repair: Display and Buttons Frozen, Unresponsive, No Audio Out


I have been trying to get this Korg DW-8000 back in business since purchasing it from Ebay for cheap in an attempt to get one for the synth collection on a budget. The description stated, "Synth powers on but freezes up. I have switched the battery, all tactile switches and firmware eprom but none of this helped the issue. The joystick seems to toggle the parameter settings super fast generating random sound."

When powering the synth on at first i noticed that just about every LED on the keyboard was lit up solid and the display showed an upside down 99. Sometimes when turning it on and off the display will show nothing whatsoever while the arp speed light stays solidly on. When it gets in this state, you have to press the joystick up to get it back into the state with all the lights on. No audio is heard from the outputs when the keys are pressed. Sometimes a random sound will be heard when the joystick is moved around.

After searching through thread after thread I came up somewhat empty handed after trying many different solutions that have been stated. I tried to reset the memory by holding the 5 and 8 key multiple times upon startup and loading the sysex patches only to still see the same unresponsive issue. The battery had been replaced by the previous person working on this keyboard, so I don't think that has to do with the issue at hand.

I took a look at the PSU and saw that there were a few wonky capacitors and the voltage regulators looked like they had some sort of oxidation/corrosion on them. I decided to replace C11, C12, and C19 as well as all the voltage regulators on the PSU. While this did seem to help the voltages on the pins slightly, it didn't seem to remedy the issue at hand.

At this point I am starting to run out of ideas as to exactly what may be the issue here. I am not sure if it is an issue with one of the chips like the RAM, MPU, or CPU, or if it could be a completely unrelated issue all together. Any ideas on this one and some things I could check? I have been using the service manual but am starting to run out of ideas where the problem may lie. Any help would be greatly appreciated. Thanks in advance