recording using external FX

[Cee High]

I have a Mackie U.420 mixer interface. I would like to have a Korg synth keyboard playing through channel 2 (in stereo) and a Space Echo pedal with the Mackie's Aux Out's going into the Space Echo and the Space Echo's outputs coming back onto Channel 3.

Wouldn't I be hearing both the dry signal (from channel 2) AND the wet signal coming back to channel 3, playing together?

I want to be able to play my source material and run through the Space Echo and ONLY hear the wet signal, so that I can record the wet signal coming out of the Space Echo.

I'm trying to use the Space Echo as a type of Send/Return.

How would I achieve hearing back only the wet signal coming from the Space Echo pedal?

 

[Mad Phonetics]

1) Put the fx pedal between the synth and the mixer

or

2) if you wanna use it in send return configuration simply turn down the volume of the dry channel.