Korg Poly800/EX800 Users

I've done the slayer mods on my poly800 and have heard about doing 
the same to the noise level pot. but i was wondering if anyone had 
heard of adding an input so i could run what ever i wanted through 
the the poly800's filter.  this guy i bought my korg mono/poly from 
said something about it but never sent me the schematic like he said 
he would.

>I've done the slayer mods on my poly800 and have heard about doing 
>the same to the noise level pot. but i was wondering if anyone had 
>heard of adding an input so i could run what ever i wanted through 
>the the poly800's filter.  this guy i bought my korg mono/poly from 
>said something about it but never sent me the schematic like he said 
>he would.  
>  
>

The poly800 schematics can be found in the file section of the group.  
If you check the "poly800text.txt" circuit description, it says the 
filter and VCA part of the circuitry is circuit 27, which I think is on 
p800_2.gif.
There was talk about this a while ago, but I can't remember what the 
recommended method was.  But I'm fairly sure it was fairly 
straight-forward.  Maybe it'll be somewhere in the archives?
Sorry I can' be of more help at the moment, may get around to searching 
the archives and see what I can find

Lee
http://www.baudalign.com/poly800.html

OK. so im not really an electronics guy.  but i did take a class in highschool and can am pretty good at figuring stuff out with a little help.  I forget how IC's are numbered.  what i can remember from highschool is that you start at the pin with the circle above it is ground or something.  so if anyone can give me a refresher about that....that would be cool. also.  I looked up on poly800text.txt like i was told and found that on IC1NMJ2069  sig1 and sig2 are DCO's 1 and 2 mixed in....does that mean that one of the sig's is ground. otherwise why would it be worded as mixed. 
 
what ive gathered is that i can put a input in place of pins 20 and 21 on IC1 but i'm sure which one is ground and if neither is ground then which pin is ground?  i know to someone with alot more electronics know how...these questions seem dumb and probably means i shouldnt be fucking around with my keyboard but thats why i have 4 of them.