DIY Leslie--AC vs DC motors?

[redoctoberff]

I'm trying to decide what sort of motors to use in my DIY Leslie project. I like the idea of the two speed Leslie motor from a dismantled organ, but I worry that the speed won't be fast enough for the upper horn, because its designed to turn one of those foam rotors. (Would the reduced weight/drag have any real effect on the motor speed? I thought they were supposed to function at the same speed within a certain weight range, which would eliminate that possibility.)</P>


The speed adjustmentseems to be the main issue. I was tempted to use DC motors as I've seen done before, because you can adjust the speeds as you want, but I'm told that the brushless DC motors are the only ones that would work, others would be too loud, would interfere with the amp, etc. The problem is how absurdly expensive those brushless motors are. Can it be done with normal, 12V DC motors?</P>


The other option is finding AC motors and trying to adjust the speed with pulley size, but I haven't yet found any good ones. If someone could point me in the right direction I'd be much obliged. Its also hard to find four motors at an affordable price...</P>

[Hammond101]

Re: DIY Leslie--AC vs DC motors?



I think the DC motor idea wouldn't work out very well. Noise aside you would need a pretty hefty power supply to have enough torque. You can use Leslie high speed motors and add a two speed kit or get a set of Leslie speed motors. Either way the piper must be paid.</P>


The wieght of you tremulants will only effect speed up and slow down time not the total RPM available.</P>


Just my 2C,</P>


H101</P>

[geoelectro]

Re: DIY Leslie--AC vs DC motors?



All the Leslie motors spin at the same RPM (60hz) The speed differences are accomplished with the pulleys. However, there are different torque motors out there. I have seen motors from built-in Leslies that are too small for a standard full size lower rotor. Any size Leslie motor would work fine on the upper.</p>

BTW...Hammond Suzuki IS using DC servo motors in some new products.</p>

Geoelectro
</p>