Adding Weight to 122 Horn Rotor?

[ts808]

Hello,
I read in a different thread about adding a steel bar to the horn rotor to enhance the sound of the changing speeds. Since I had a spare horn I did this using a 14" long square steel bar weighing 2.0 lbs.
It really works well and the sound is much more pronounced. Luckily it's surprisingly well balanced!

The question is: Will the added weight kill the motors prematurely? I don't know the weight of a lower drum rotor but it's a lot heavier than the plastic horn and those motors have been fine for years.
Either way it's easy to undo if it was a bad idea.

Thanks

[Roger Memphis]

No, this will not noticeably damage the motors... they are impedance-protected types designed to withstand even locked rotor conditions. Your modification will, however, wear out your drive belts much faster.
Roger Memphis

[David Anderson]

Your modification will, however, wear out your drive belts much faster.

Not to mention the horn bearings.

[ts808]

Thanks a lot, you guys. All good things to keep in mind and a reminder that any modification can have unintended consequences.

That reminds me, if anybody wants to do this mod, and your Leslie spins fast when powered on, hopefully you have a good way to make sure things are balanced before you turn it on. Otherwise serious damage could result from the heavier, unbalanced rotor. In my case the 122 has fast, slow, and stop so I was able to power it up, then switch the speed to stop., then install the modified horn and try it on slow speed first, then switch to fast briefly to make sure it was OK.
Tom

[Tim_at_Jonas]

Why not just adjust the tensions of the belts?

[KC9UDX]

Or trade some poor sod for his Rotosonic.

[ts808]

When I first read about it I was just curious to see what it would sound like and since I had the spare rotor it was an easy choice. And the sound seems more pronounced than what I got out of adjusting belt tension.
What's the story with Rotosonic? . . .don't know about those.

[KC9UDX]

A Rotosonic Leslie has a rotating mass with a large amount of inertia.

[ts808]

Ha, that's NOT what I was after. Mine doesn't sound do that! But thanks, now I know.

[ts808]

If you want to hear what sent me off on this project, listen to Pink Floyd's Breathe, starting at about the 3:13 mark through about 3:37, particularly those last 4 or 5 seconds. I always assumed it was all Wright's Leslie horn rotor but maybe there's more to it. Any ideas? BTW, it's much clearer on CD than on my computer.

[geoelectro]

To me it sounds like a typical two rotor Leslie. The lower rotor slowing down slower than the upper. (Listening on an iPad)

Geo