>If you were to measure the frequence reponse of thing I bet it would be very non linear <snip>

It can't be measured man - it's like - ethereal ... :)

Actually - it also tends to change over time as the tubes get hot - and with the complete randomness between the speed, direction, and position of the horn and bin at any given point in time - it's very hard to even measure - much less reproduce well. Finally - no two setups ever sounded the same. We used to make jokes that a hammond and leslie never sounded good until they got beat up, had a few beers poured in 'em, dropped a couple times, etc.