[sdiy] IR3109 (OTA-based) filter question

[Mike I.]

Hi Dave (and list),
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.
Mike

DCMagnuson at aol.com wrote:
> 
> Hi List,
> 
> I've got a few questions regarding OTA based VCFs.