[sdiy] NJM-2069 internals. Was: Re: SSM2040

[Bob Weigel]

2069 is the filter used in the poly800, DSS-1, and DW8000 at least.  
Really lends itself to ominous sounds I think. The DSM-1 has 16 of them 
but, sadly, has no resonance control I was shocked to find when I got 
mine.  I figured they would have made it so you can directly import the 
DSS-1 sounds to the critter but Korg was..ummmm....ummmmmmm STUUUUUUUPID 
that day :-).  (Like I say it seemed to be a thing with Korg.  At the 
end of a production run they would have a bunch of chips leftover or 
modules.  And they'd make something that used them all up real fast.  
With the Korg 35 it was the sigma where they dumped 13 of them in it and 
did the same thing.  There is no user control of resonance on any of 
them!  Except as it's preset in a tab selection. 

Anyway the DSM-1.....They put in a HD disk drive, doubled the memory as 
I recall and made it multitimbral and it can be run as 16 voice with one 
osc per voice or double with independent filters of course.  But only 
sounds that don't exploit resonance can be cloned and you have to 
manually set everything up.    And that's the reason the DSS-1 is still 
hooked up in my studio and the DSM is collecting dust at the moment.  I 
may try to do a modification that gives dynamic resonance control 
someday who knows :-).  Or I may just sell it.  It's so heavy.  I put it 
in my rack and couldn't hardly lift it with the MKS70, JV1080, K5000 and 
DM5.  It's 45 lbs or something as I recall.  One strange boat anchor 
:-). On the SDstudio page from sounddoctorin.com you can click on the 
first keyboard station and then the DSS-1 for an mp3 of me playing a few 
sounds on it.  -Bob

anthony wrote:

> What was the NJM2069 again? I remember seeing an NJM2069 called for in 
> something I needed, but I forget what...
>
> I have soem NJM2058's, but they're a totally different monster I'm 
> sure: a quad version of the NJM4558 - cool, eh?
>
>
>> On Nov 4, 2007 12:56 PM, Bob Weigel <sounddoctorin at imt.net> wrote:
>>
>>> Hehe.  yeah it definitely wasn't an exhaustive list.  Actually I think
>>> the NJM2069 you refer to is one of the finest of the whole bunch.
>>
>>
>> I agree. I've never been able ot find a solid opinion on what's inside
>> the filter. Many have said that it sounds like a cloned 2044.
>>
>> Does anyone have any insight on the internals of this chip? Any reason
>> why it would or wouldn't be a 2044 clone?  I'm not talking about the
>> obvious differences such as integrated VCA and VC input mixer. I'm
>> referring to the topology of the filter as well as details of the gain
>> cells.
>> _______________________________________________
>> Synth-diy mailing list
>> Synth-diy at dropmix.xs4all.nl
>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>
>
>
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>
>