[sdiy] IR3109 (OTA-based) filter question

[DCMagnuson at aol.com]

In a message dated 5/18/01 12:15:33 PM Eastern Daylight Time, 
marmot1 at magma.ca writes:

> The Roland JP-6 has a multi-mode HP/LP/BP VCF which apparently (I don't 
>  have the service manual) uses the IR3109. The IR3109 is  used in the 
>  JP-8 VCF which has selectable 2-pole and 4-pole LP modes. The Roland 
>  (Boss) RPH-10 phaser uses two IR3109 for the allpass filters. I have the 
>  RPH-10 schematic and can send it if you wish.


I've figured out the 2-pole/4-pole switch, and thanks to an earlier reference 
to the CEM3320, I believe I've figured out the HP/LP/BP switching as well...  

I'm currently trying to decide on the best method if implementing the 
switching, since I'll be making/breaking several connections simultaneously.  
I'm probably going to use 4016/4066 analog switches unless someone has a 
better idea

Dave