probably a stupid question.. but?

[syntaxera]

If you wanted to mix two inputs, or a wet / dry signal....

What would be the best way to do it?

Is it as simple as a double 100k audio pot?  or is there more to it...

There are a lot of pieces I am working on that could benefit from it..
just can't seem to get my brain around how to do it though.

Any wiring diagrams, links or schems would be much appreciated

[Jdansti]

Here's one option:

http://www.diystompboxes.com/smfforum/index.php?topic=56277.0

[WaveshapeIllusions]

You want to first make sure each line has similar source impedance to prevent them from loading each other. A classic way to mix is an opamp set up in the inverting configuration with an equal resistor in each line. You could use a dual-ganged pot to set the levels of each before the mixing resistor.

Hope this helps.

[syntaxera]

i tried the passive mixer before making this post... FAIL.  lol
it was cutting one signal off from another..  problems everywhere.

i think an opamp would be the best way to go....  any circuit suggestions?

also what about a simple one knob wet / dry for a delay unit... any ideas? 



this wet / dry thing is really catching me up..  a lot harder than it would seem
and changes totally depending on what circuit you are doing it with

ugh

[Jdansti]

Here's another option using an FET.

http://www.aaroncake.net/circuits/mixer1.asp


From the website:

R1, R3         2   10K Pot   
R2, R4         2   100K 1/4 W Resistor   
R5                 1   6.8K 1/4 W Resistor   
C1, C2, C3.    3   0.1uF Capacitor   
Q1                 1   2N3819 Junction FET   

As many or as few channels as are required can be added to the mixer. Do this by just duplicating the input "sections" which are shown on the schematic.  A shielded case is probably needed to reduce hum and help stop oscillations.  The circuit can be powered by a single 9 volt battery.

[syntaxera]

great circuit!  thank man...

any idea how I could do wet / dry for a delay with only one knob?

wait..  I can just use a Double Pole 10K A Pot correct? 
that was one is getting turned down... while the other is being turned up..  correct?

If so, that is very cool... and super helpful

[Jdansti]

Right. If one input is wet and the other is dry, you could "pan" between the two with a dual ganged pot. As you mentioned, you'd want one to be going up when the other is coming down. These types of pots are sometimes called "balance" controls. A stereo pot arrangement would have both going up or down at the same time.

Someone else might know of a more "elegant" way of doing the wet/dry mix.