I'd love to see that schematic for your switching.
I wondered if Leslies are usually used with a dry speaker cab so the signal gets canceled and/or reinforced as the leslie spins.
Which do you prefer leslie alone or two speakers?
It's pretty simple - just a couple of relays and some driver jfets. I used a Tyco RTE24006, which is fine for my 18 watt, but may not be sufficient for a larger amp. Also, the power supply is pretty simple, and worked fine for me, but you may need to do something a bit more elaborate.
It's not a question of whether it's better with or without the static speaker, but which better for the song. Also, the phase shouldn't make much difference, because the phase of the Leslie changes throughout the spin, so you would just have the same phase relationships, at opposite sides of the spin.
I'm with you on that. Slow's too slow fast is too fast. Variable speed would be nice but I don't think itJs possible with those motors.
It says P1 connects to S2, but the numbers don't seem to match up.
Trust the numbers or trust the position?
You can do variable speed with induction motors, but it really isn't simple - at least not electronically. You need something called a VFD (Variable Frequency Drive). Induction motors speed is a function of the frequency of the AC power and the number of poles on the motor. In order to vary the speed of the motor, you vary the frequency of the power, but (as always) there is a problem. Obviously, in any inductor the impedance varies with frequency, so as you slow down the motor you will draw more current, and you can burn out your motor. And of course, as you speed up the motor you'll draw less current and can just stall your motor.
So, you either need to limit the range of the speed, or you need to limit the current at the same time as you vary the frequency. There are a couple of commercial units that are designed to give variable speed to single speed Leslies, but they are a bit pricy (search for Leslie 2-speed conversion, if you wish). The variable frequency part is actually pretty simple to design (a few diodes to give your self + and -60V rails, and an big MOSFET H bridge controlled by a variable frequency oscillator), but to limit the current you either need put in a bi-polar current limiter of some sort, or vary the voltage of both rails. The voltage is easier, but you need to do so of really rather high currents, so you can't just whack in a LM317 or similar voltage regulator. Honestly, if I could afford it, I'd probably just buy one of the commercial versions, as it's quite a lot of engineering.
Gabriel
