[sdiy] question: a simple blend circuit?

[mark s]

use a push-pull pot (mouser has them in 500k value...)  and you won't have 
to drill any holes.... worked great for my guitar.
cheers
mark

At 07:41 PM 1/27/2004 -0400, you wrote:

>----- Original Message -----
>From: "Daniel Englbert" <denglerthm at hotmail.com>
>
> > hi, i'm a relative fool when it comes to diy stuff, building guitar pedals
> > from diagrams and kits is all my experience..
>
>Join the club!
>
> > is this hard to do? do i need opamps and a little perfboard? i have no
>idea
> > how to do this, if anyone could help or point me to some schematic (or
> > better yet component wiring diagram) i'd be SUPER happy!!!
>
>Well, it sounds like you are happy with the signal from the piezos as
>is...if it doesn't require any amplifying/buffering, just try a pot in
>there. It might be that no other circuitry is required.
>
>If you need to boost the piezos a little, or just buffer them, a
>non-inverting opamp circuit might be used...I bet one of the clever gents
>here could tell us if it's possible to do "phantom powered" (I think this
>only works with XLR connections to powered mixers, but I thought I saw an
>"unpowered" guitar buffer somewhere...), or if you need to stick a battery
>in under the pickguard. A 9volt will last forever in a circuit like that.
>The basic design of a non-inverting amp is at
>http://www.ecircuitcenter.com/Circuits/opnon/opnon.htm
>You probably need non-inverting, because you want to blend it with the
>pickup signal, so the phase needs to be the same. Er...that is, if the
>devices both have the same phase to begin with; I am getting out of my depth
>here. If mixing them deadens the audio, you could try an inverting amp
>circuit :)
>
>Check out: http://www.muzique.com/lab/buffers.htm , there's an opamp circuit
>part way down the page that might be useful if all you need is a buffer
>(unity gain), and a nice overview of various transistor circuits for the
>same purpose.  I *know* there are websites dedicated to this kind of thing,
>maybe someone has some pointers.
>
> > i could barter some litttle bits of gear for the help! guitar pedals or
> > something like that
>
>I'm sure that isn't necessary, someone will help ya out enough to get that
>working. Someone who knows more than I do, I bet.
>
>-Darren