How would I make this Line-Level In/Outs?

[steveyraff]

Hey all,

I require your vastly superior expertise 

I am building one of these:



It's a HPF Pre 2. The specs are listed as "Input impedance 10 MegOhms / 220 pF".

A guy asked me to make one for him but asked: "Do you have a line-level input/output impedance version of this pedal?". He also asked about having it in stereo for using as a monitor controller for Hi-Fi speakers.

Can I do this - and how? lol    I presumed for stereo I'd have to just build two, or maybe there is an easier way using the one volume and one frequency control?

Anyway, this is all something I'm really not used to doing so any basic help is cool. Thanks.

[pokus]

To make it a stereo device you have to build the veroboard twice and get a stereo pot for volume. But as your freq pot is also a stereo one you need another one. Then you can control the freq of left and right differently. I think that's the easiest option cause I've never seen a pot with 12 lugs.

For the line in maybe a easy voltage divider is practical to set the high input voltage of the line in (about 2V) to something more guitar pickups like (100mV).

[Phoenix]

4 gang pots are rare (especially in audio/log taper), but here's one supplier with a minimum order quantity of one: Mouser.