Hammond A100 connected to Leslie 3300

Long time no post.

Using a very slightly modified version of the circuit you can find here, and information about the 11-pin connector here, I built a box to connect my Hammond A100 to my Leslie 3300. Here are some images:


























The red button is connected to Leslie pins 5 & 6 so that I can turn the Leslie on and off from the box.



























The toggle switch is my Main-Echo-Ensemble switch, though since it is a DPDT Toggle switch it is just an M-E for now. I will consider putting in a proper switch to allow a mix option between the internal and external speakers, but for now I am happy being able to easily switch between the two.


























For the most part, I am quite happy with the results. I do need to hide the wires (where do people run the half-moon switch wires on an A100?).


























Since I no longer have reverb when using the Leslie (since I tapped into the preamp and not the main & reverb amp outputs), I've been hearing reverb in Hammond recordings lately. I think it would be easy to put an insert into the circuit that would let me put a reverb foot pedal in; but that is down the road.

The 3300 is a fabulous Leslie, especially after replacing the factory 12AX7 with a 12AT7 (thanks Jim Alfredson!). A new concern though, is that with the higher fidelity of the 3300 compared to the A100s internal amps and speakers, is that pops, clicks, and crackling noises are much more noticeable now. My next step is to order some de-oxit and clean all of the tube sockets in the A100 - I hope that resolves the noises.

Thanks to Jeff Dairiki and Harvey Olsen for the original circuit schematic.