ARP Filter Chronology, was Re: Surface mount synths??

[Sean Costello]

At 01:17 PM 7/11/96 +0300, you wrote:
>On Wed, 10 Jul 1996, Kevin Lightner wrote:
>
>> Any thoughts on making a surface mount, all analog "voice" board, similar
>> to an SEM or ASM-1?
>
>I've played with that idea too. I even designed a filter board for the
>Odyssey which combined two of the original filter designs (4023 2-p
>biquad and 4035 4-p ladder) into a single 4035/4075 compatible module.

The ARP terminology has me confused.  Here's all I know about the ARP filter
modules:

4012 - Moog ladder filter copy, used in early 2600, Pro-Soloist, and
(debatedly) the white-faced Odyssey.

4023 - SEM-type state variable, used in white-faced Odyssey.

4035 - never heard of it before.

4072/4075 - 4-pole filter (probably the one covered in US Pat. No.
4,011,466), using LM3900 and 4 PNP transistor differential pairs. 

Is this about right?  When was the 4035 used?  How do each of these sound?
Also, is the 4075 the filter that is sitting in my (really, really broken)
Omni?  I've hesistated at taking the little sub-module off of the main
filter/ADSR board, but it has 3 groups of 3 pins connecting it to the main
board, and several (6? It's hard to see) transistor pairs wrapped in copper.

Any information would be much appreciated.

Sean Costello

P.S.  Thanks for all the patent information, Joachim.  I was able to make
copies of the ARP and Moog patents you referred me to; very cool stuff.  One
question:  was the multi-mode filter (3,805,091) used in any commercial ARP
synth?