tonewheel.com has the schematics for building a universal Leslie adapter. It allows the use of pretty much any Leslie cabinet with a Hammond organ equipped with an 122 type (8000 series) control kit. The schematics have been designed in a modular form so you can select the building blocks necessary for your specific application.
The Hammond expression pedal seems to be a mystery to many players, especially those that are more used to playing on clone wheels, even though at least some of these model the original Hammond expression pedal behavior very closely. Many people seem to think that the expression pedal on a Hammond is only used to control the volume of the organ, but this is only part of its function, it also acts as a (passive, non-linear) equalizer (EQ). When the volume is low, higher frequencies are much more attenuated (reduced) than lower ones, leading to a much bass-heavy sound and less pronounced highs. The reverse is true when the expression pedal is put to full throttle (loudest volume), which results in a much brighter sound with relatively reduced bass content.
Thus, you can influence the character setting of the tone by opening or closing the expression pedal. This may lead to an undesired low volume when aiming for a more bass-heavy tone with les emphasized highs, but this can be counteracted by increasing the amplification. This may be accomplished by turning up the Leslie or other amplifier you may be using to amplify the Hammond. This may also make drive your amp into overdrive more easily, so you may need to find the right balance in the settings of the amp and the expression pedal to give you the desired tonal balance as well as a usable travel to adjust dynamics using the pedal.
Personally I like overdriving the Leslie to get a bit of growl, and this gets much easier with the Leslie on very loud, and playing the expression pedal at the low volume end, pushing the Leslie into a nice drive when increasing the volume on the expression pedal.
In a previous post I explained how to use the Rotor plugin and the Overdrive to add a bit of drive and Leslie emulation to a real Hammond while recording on Logic Pro X. Further along experimentation with this setup, I’ve ditched the Overdrive plugin, and have switched to using the Distortion II / Growl Distortion Light as a favourite driver for the Rotor Leslie emulation. This gives a very convincing bit of dirt to the sound. Here’s an example:
Something else I’ve been experimenting with, with better and better results, is using the Rotor in Logic, based on suggestions from Jim at the Organ Forum. If you combine this with the overdrive, or one of the amp simulators (‘Moving Air’ is a good one) you can get very good results, and this works very well for recording, taking the signal directly from the line-out on my A-102; I’ve been struggling with how the Vent is sitting in the mix, and the levels I get from it. This may just be related to my own setup, but I’m pretty much using Overdrive / Amp modeller / Rotor now, sometimes using Spreader and Exciter for an even bigger sound, and either the standard bus 2 platinum reverb (add other buses with reflections to taste) or a modelled reverb room.
Don’t forget to set the record mode to Latch or Write to capture Leslie-switch events (I send my CU-1 through a foot switch input on my interface for slow / fast switching).
For an example how this sounds:
This is what happens when you add a Saturn synth driven by a guitar through midi to a Hammond tonewheel organ: Bliss!
A very satisfying heavily driven sound by using the vent drive at about 3 o’clock and using pedals to thicken the drive and the sound significantly when compared to just using the manuals.
Here’s my latest Wikiloops Album:
I’ve compiled a list from information available on the internet that may help date a Hammond console (A-100, C3, B3, D-100, RT-3)
1958 – Vibrato line box changed from wood to metal
1960 – Side blocks change from wood to plastic
1961 – Pilot lamp added
1962 – Vibrato knob changed from smooth to ribbed (‘fluted’)
Mid-1962 – AO28 transformer colour change from silver to black
Spring 1964 – Start of using red caps
1965 – Hammond script changed from small to large with new logo
1965 – Foam replaces felt
1965 – Introduction of R/C (resistor/capacitor) networks to tones 37-48 to reduce hum and crosstalk
1969 – Drawbar plastic knob style change to have engraved tones
Additional information can be gleaned from the components in the organ. Speakers (A-100 series) are usually stamped with a production date; the same applies for tubes / valves as well as capacitors.