[sdiy] hammond imitation

Mon Nov 4 22:19:47 CET 2002

The hammond key contacts are not arranged to close simulaneously...
they close in a harmonic order like 8' then some mix then 4'

or something like that. I know they don't close together, but don't know the order...

This can give some odd effects when the keys are pressed fast or slow... almost a variable attack. tease the keyboard with a real
slow press and see what happens...

Some people play with the motor controls to get odd modulation / pitchbend... but NOT what you're talking about...

could you be hearing the normal Leslie speaker at chorale speed...
Most hammonds are so equipped (and I'd never turn it off ;^)

H^) harry

>Hi,
>recently I have run my CX-3 organ thru my Storm Tide Flanger and I used the
>Envelope Follower modulation of delay time to get some "outer space"
>sounds.
>Now with this setup still intact and the Flanger accidentially left in the signal
>path, I tried to play an "ordinary" hammond sound. Noticed the Flanger immediately,
>and switched it off.
>And then switched it on again.
>I found that a _tiny_ bit of envelope follower to modulate the delay time (und thus
>to modulate frequency) was very pleasant _and_ I even think it makes the Hammond
>sound more realistic.
>I wonder if this is really true (I have also changed the frequency response with that
>flanger, obviously, so the FM effect might not be the important part really), and
>if it is true, then _why_?
>Is there a mechanisms on a real tonewheel organ that will slightly modulate the
>frequency when keys are depressed ??
>I really don't think so, but if I make some wild speculations, I could come up with
>an idea to explain this. (I mean this phenomenon of which I'm not even sure
>that it exists. (;->) )
>Here we go: 
>The tone wheels are operating with an electromagnetic pickup. If this pickup
>is connected to the electronics by pressing a key, it is _loaded_. This load
>will draw some energy from the mechanical system.
>Now the big question is: Is the electrical load heavy enough? And is the 
>propulsion for the tonewheels "soft" enough to cause any perceivable
>effect on momentary frequency??
>I really don't know enough about hammonds to answer these questions,
>and my guess for an answer would be "probably no". But then again
>I heard the mixing of drawbars is done with resistive wire (?) and a
>transformer, so I guess it's not all high-impedance stuff without much
>power consumption, is it?
>Any comments welcome,
>JH.