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moog slayer mod info / poly-800 mdk - sysex for mk1s!

moog slayer mod info / poly-800 mdk - sysex for mk1s!

2002-11-06 by funkwit

hey everybody,

for those of you who have been asking about the moog slayer mod, the
picture that olaf_nv uploaded is a nice, informative diagram. atom
smasher's original site didn't show you how to make the mod
switchable, so if you want to keep the original filter functionality,
it's definitely a good way to go. props to olaf for the diagram, and
also to peter ullrich (who i think i know from the sgroup list? ^^;;)
for pdfing the original site.

fwiw, if you go check out http://www.synthmod.net/ you'll see a
server message - evidently atom's domain has been having technical
difficulties, but will it will be back online soon. atom smasher's
done some cool mod-work on things other than poly/ex-800s; it'd be
cool to see it all in the form of an actual, organised site at some
stage.

semi-gloating (but hopefully informative) part of message -

i mentioned in an earlier post that i'd found a mint, uninstalled
mdk - for those of you who may not know, this is the midi dump kit
for the original poly-800 (mk1), which gives it the ability to send
and receive sysex information, and gives *you* the ability to call it
a "poly-800 plus mdk". it's a bit fiddly to install (some trace
cutting is involved - i'm a kamikaze circuitbender so i used a dremel
to do this), but otherwise fairly straight-forward. with this new
addition, i can now call my synth a "japanese reversed-keys korg poly-
800 mk1 plus mdk". it has my ultimate respect, heh.

tech details - all you need to do is solder in 8 wires connected to a
harness at various points on the klm-596 board, cut traces in three
places (two of which are very close together, so really you're only
going through the process twice), solder in two jumpers, replace the
stock 2764 ep-rom with a preprogrammed 27128 that comes with the kit,
add the new klm-680 pcb just above the battery case (ever wonder what
those extra spacers were for?), then attach the harness to the new
pcb and fire it up. cross fingers and any limbs or other extremities
you can. assuming you haven't fried anything, it should work.

i've picked up soldering skills and such from my circuitbending
adventures, but i don't know much about digital electronics.
however, since i have the retrofit instructions here, i can scan and
upload them at some stage - they include the updated memory map, full
instructions for the retrofit, and a schematic of the klm-960 pcb, so
i assume it would be possible for some bright spark (pun intended)
with access to one of the programmed 27128 ep-roms and an ep-rom
reader/burner to read the rom image, burn new ones, and then add this
retrofit to their own (or others') poly-800s completely from
scratch. right? the instructions say they're intended for use with
the poly-800 service manual, but i got away without it, not that i
was trying to do anything fancy.

as far as actual *usefulness* of the mdk retrofit goes, i'm yet to
test this ^^;; - as hexafuzz mentioned in an annotation on the mdk
user's guide currently residing in the files section (text version
still on the way, i just haven't had time, sorry), you need software
designed specifically to make the midi dump request to the poly-800,
as it has its own unique "poly-800 plus mdk id" and refuses to send
without it. this is kind of unfortunate, but you should be able to
set up any computer-based sequencer or sysex utility to do this. as
another option, there's the korg mex-8000 memory expander (which i'm
kinda on the lookout for), which lets you load and save four banks of
patches... i think these are also really hard to find these days,
because they work with many of korg's synths of the time (the dw-/ex-
8000, ex-800, poly-800 mk2, and poly-800 plus mdk - maybe others as
well). either of these options would be cool. it's not so likely
that a hardware sequencer will let you send the dump data request to
the mdk, though - my mc-500 doesn't with the standard bulk libarian
software, anyway, although i guess it might be possible to find some
way around this.

so there you go. hopefully that will help some of you with poly-800
mk1s and a desire for some sysex action out; if anybody's desperate
for the ep-rom image i can try to find a reader somewhere and make it
available along with the schematics. if anybody's desperate and
*generous*, i'd accept donations for doing so...? cash or ep-rom
readers/burners gladly accepted, cash extra-gladly. *grin* [sorry,
i'm trying to save for a roland sh-5 and a modular, i'm in greed-mode
atm.]

hope this is useful,

-gareth

Re: [korgpolyex] moog slayer mod info / poly-800 mdk - sysex for mk1s!

2002-11-06 by Alexandre Souza

> however, since i have the retrofit instructions here, i can scan and
> upload them at some stage - they include the updated memory map, full
> instructions for the retrofit, and a schematic of the klm-960 pcb, so
> i assume it would be possible for some bright spark (pun intended)
> with access to one of the programmed 27128 ep-roms and an ep-rom
> reader/burner to read the rom image, burn new ones, and then add this
> retrofit to their own (or others') poly-800s completely from scratch.

I can do that, if you send me the schematics and ROM. If (and only
IF) this board doesn't use any special components from Korg, it is
easy to reproduce and publish on the net ;o)

Re: moog slayer mod info / poly-800 mdk - sysex for mk1s!

2002-11-07 by gareth davies

hey guys,

i did a bit of looking around on the web for cheap
eprom readers/burners after sending that post, and
i've found a diy project that looks as if it will work
fine - so i should be able to read the eprom image
myself. i should have mentioned before, i'm in
australia - because of this, if nobody else on the
list is in the melbourne area and has a working eprom
reader, i'd kinda prefer to do it myself...
otherwise, if i pull out the 27128 and ship it
internationally, i'll have a dead poly sitting around
for at least a couple of weeks. and that thought just
makes me nervous. :]

the klm-680 schematic itself is really simple...
nothing proprietary, just two 40H000P ICs, two
0.1u/25V CEs, and (on the official PCB, but not on the
schematic) two resistor-like components with a single
black line on the body, which are just glorified wire
links as far as i can tell. it should be pretty
straightforward to design a pcb.

the only problem with all this is that i'm *really*
busy at the moment and will be until sometime next
week, so i hope you don't mind if i wait until then to
scan the docs and (maybe) build the eprom burner.. i
should be getting a webcam in the next couple of days,
so i can probably obtain some decent photos of the
klm-680 pcb. but there you go - it's all pretty
simple really. the most time-consuming part of the
installation process, besides cutting those traces, is
actually *finding* where you're supposed to solder the
wires from the klm-680's harness. it's not really
difficult to do, just tedious. :] if i can sort out
this eprom image it should be fairly simple to add the
retrofit to other mk1s.

by the way, if any of you use software plugins, check
out the range of shareware softsynths designed by
mikael, who sold me the retrofit kit... he's from
sweden and is a really nice guy; i was prepared to pay
more than i did for the mdk but he said he was happy
just to get rid of it. all i wound up doing was
buying him a cd (which turned into a bit of a saga,
but still) - it'd be cool to think that i could help
promote his work in return.
http://www.mhc.se/software/plugins/

anyway, if anyone else has the updated eprom and
already owns a reader/burner, it'll save me the
trouble of building one. :] let me know if this is
the case. otherwise, i'll get onto it asap.

-gareth

=====
g-reth davies
gklitschprizm mod\
(beware the gklitschkitty)
soul.devour;
<[hyphen x 0.5]>

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Re: [korgpolyex] Re: moog slayer mod info / poly-800 mdk - sysex for mk1s!

2002-11-07 by Alexandre Souza

> the only problem with all this is that i'm *really*
> busy at the moment and will be until sometime next
> week, so i hope you don't mind if i wait until then to
> scan the docs and (maybe) build the eprom burner.. i

For me it is OK, I'm looking forward your packet with the schematic
and ROM ;o)