Leslie top rotor interchangeability?

[Guest]

Hi guys. I have a question that someone here may be able to help me with.</p>

I have a Leslie 46W. Will the top, high frequency rotor, interchange with some of the other models like a 122 or 147? The 46W's top rotor has a diffuser cone mounted in the center of the throat on the horns. It is my thought that if I did away with the diffuser perhaps I could get more effect out of the top rotor. Does that make sense? I am aware that only one horn is open for business. The other is just for balance. I am looking for advice about that change.
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The Leslie works great but I don't seem to get as much effect out of the top rotor as on other Leslie models I have heard and used. I could always remove the diffuser cones but if it didn't work as well then I am committed and would not be able to undo it. I would rather just change out the rotor if possible. I have seen Leslie rotors with no diffuser in the throat but I'm not certain what model Leslie they were in.
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Ken
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[toasterDude]

Re: Leslie top rotor interchangeability?



Hi Ken, I'd recommend you leave the deflectors in place. Leslie designed the horns that way for the same reasons they designed thelouvers on the cab with that oblique angle to them. As I understand it, the idea is that if you just had the open horns, the listener would perceive way too much tremolo (amplitude modulation) and not enough vibrato (frequency modulation.)--Sort of a heavypulse or blast of volume, each time theactive horn passes so it's pointed directly atyou.</P>


All Leslie hornswere made with the deflectors in place, so if you've heard Leslies with no deflectors, they've been removed by a previous owner.Lots of rockorganists seem to cut them out, probably from a mistaken belief that removing them will yield more volume. But, if you'e accustomed to the sound of a Leslie with the deflectors removed, you're probablyused to hearing the additional tremolo (I've heard it described as "that nasty wha-wha-wha sound"), especially if you were playing/listening to one of the Proline Leslies like the 330, 760, 860, 900s -- these don't have the angled louvers, but instead just have horizontal slats plus grill cloth. That would explain why you perceive the horn effect on your 46W to be too mild.The combination of non-angled louvers plus no deflector cones would make for a very pronounced tremolo; but the classic effect is rather more subtle.</P>


Of course, you may alsobe remembering the sound of a"Rotosonic" Leslie like the 710 and others. These have 6x9 speakers mounted inside a rotating drum, so they produce a much heavier tremolo as well. --Again, you can imagine the heavy pulse that would result from a speaker wheeling around and firing right at you; then 180 degrees in its rotation later, it would be firing directly away from you, so the perceived amplitude would drop drastically... then right back at you again, and so on.</P>


If you can't help yourself and you remove the deflectors, you can always buy a new set of horns if you decidelater to return your 46W to stock. They're just plastic, so they're still being made and can be bought for around $40 from any number of suppliers.</P>


TD</P>

[Brendon Wright]

Re: Leslie top rotor interchangeability?



That FM effect is also known as the doppler effect (when frequency oscillates) rather than AM which is just volume oscillating.</P>


The defelctors were designed to enhance FM and also have some AM. Take the deflectors off and you get all AM and much less FM.</P>