Organ Grinder pedal doesn't grind (much)

[DavidMunich]

I just purchased the Organ Grinder pedal and stuck it between my Electro 6D and my Leslie 122 (via a TrekII preamp). Both controls work and I'm seeing the blue LED, but the sound doesn't change much. When I compare it to the pass-thru signal, the sound is louder and it definitely has more presence, but I not hearing any distortion. No grit like I hear on the demos. I'm not getting what I paid for.

I searched for tips and a possible cause could be a weak input signal, but the signal is coming directly from the Electro and sounds plenty loud when I crank it up.

I'm using a brand-new 9V. battery. Does the pedal work any different with a power supply?

Thanks for any tips or ideas.

David