Korg DW-8000/EX-8000 -1986    Weight = 24 Lbs. Number mfg.= 20,000 MRP=$1295


User Manual: synthmanuals.com
Reset Proceedures: Hold [1]and[8] buttons while powering up for EX8000 at least.
Operating System code: version 12
MIDI or other control protocol:
Software related Links:
Patches or knob settings:
Circuit Overview: below
Scematics/Service Manual: fdiskc archive or synthmanuals.com
Common Service Issues/Tips: below
Parts Sources: Keys knobs semiconductors misc
Uncommon chips/modules used: NJM2069 Korg marked filters, Wave ROM etc.
Modifications:
General Info Links: Vintage Synth Explorer





Circuit Overview:
      Enhanced DW-6000. Considered this as my first synth. A cool sounding hybrid with ROM waveforms and analog filters. Extra envelope control over ADSR and digital delay make for a great bang for buck machine. Excellent leads achievable.

















Service Tips:
      First there is a bug in pre-version 12 EPROM that can cause notes to get stuck. I thought it was just contacts since my keyboard had other issues...850710 was the part number on my eprom. The HN4827128-25 eprom may be tough to find but any 250nsec access time 16K x 8bit EPROM should suffice that has same pin pattern. Same keyboard as DSS-1 and bushing tends to get noisy. Haven't delved in to see what the best solution is. Both my DSS-1 and DW8000 have pretty noisy key action. I'm trying to assist someone having intermittent lock ups and 6 instead of 8 voice polyphony response on an EX8000.


I thought it might be helpful to list the diagnostics. While turning on power, hold the following key combinations in the programmer section to enter the diagnostics listed next to them:

1,2 - Displays system ROM version number. Version 850708 is displayed as "07". I...wonder if these were date codes?
It then sets write protect attribute on version 850709 or later.

5,6 Reference voltage adjust mode. See adjustment prodedures in manual

7,8 - Tuning mode. Also see manual.

5,8 - RAM clear mode. Kills all programs in memory.
Parts:
I believe you'll draw mostly blank looks from Korg on these units. I have some parts that are the same so feel free to ask what the current stock is on a given thing. Some of the less common parts are getting quite hard to find though. THings pop up on ebay now and then.. Contact