Leslie/ Vibratone cab switching question

dogload

I have a Leslie Model 18 rotary cab (the 12" speaker version) that works but there is no footswitch for going between fast/ slow and bypassing the speaker altogether. 

Does anybody here know how to build a unit to do this before I find myself seriously considering buying a overpriced reproduction from America! And if they do know how can they describe it so that a half-wit with a soldering iron (who doesn't understand schematics) can manage to build one!

Not asking much, really.

ecc83

I really know nothing  about them but if opto-isolators are needed that tells me there are some lethal voltages around and therefore such a project is not for the green beginner!

Dave.

MartinB

If they're the same as other Leslies, they have separate slow and fast motors, and switching between the speeds is accomplished by connecting AC mains voltage to one or the other.  Snaking a multi-core mains cable across a stage to a footswitch is less than ideal, so some form of relay switching is usually used.  What I don't know is whether that is already built in to a Leslie 18.  

dogload

The Leslie 16/ 18 has a little box where the mains power goes in which apparentlhy contains the electrical stuff. From the web:

The Vibnratone/Model 16 contains a little mini-chassis which contains the switching relays for the motor circuit andf a small 12 volt power supply to power the relays. The 12 volts from the supply goes out to the footswitch which selects on/off and fast/slow. Then the 12 volts comes back to the chassis and powers the relays, which switch the 120 volt line to the motors.

This is what it looks like inside:


And this pile is what I don't have:


There is a crossover in the cylindrical thing and a jack socket attached to the end of two cables for connecting amp to Leslie and then Leslie to regular cab. It's very inelegant and I don't particularly need the crossover or connection to another cab, and there was a socket that connects directly to the speaker, fitted into the back panel of the Leslie. There is a replacement available for the whole rig from HERE but I don't especially want to fork out 200-plus quid if there is a simple solution!

Here are the schematics that I have found for the Leslie/ Vibratone. Means nothing to me!

lukedlb

The crossover cable are notoriously difficult to find and unnecessary for the Leslie 18 as the 12" speaker shouldn't have any trouble dealing with the full range signal. The 8" speakers or 10" blew often without the crossover which sent the bass and treble to the power amps dedicated cabinet and the mids to the Leslie cabinet. 
I have two Leslie 16s and I have yet to find the ideal speaker and amp. Lots of trial and error so far. 
As for the speed control foot pedal, i'll send you some pictures of what's inside. It is a high current circuit so best done by a pro. 

lukedlb

Pm me as I'm bound to forget. 

dogload

Thanks @lukedlb I would prefer to do something that avoids all the dangerous stuff if at all possible. As I say I'm not fussed about the crossover especially. Do you reckon it's possible to do something that avoids the high current bit?

TBH I'm not sure I want to keep the Cab as it came into my possession more or less by default - I just use VST Leslie sims when recording but thought I might try the real thing seeing as I have it, but it only does fast at the moment, hence the inquiry about the speed control pedal.

Gassage

if ever you sell it, dibs please.

dogload

Gassage said:

if ever you sell it, dibs please.

In all honesty, I could be persuaded

olafgarten

dogload said:

Gassage said:

if ever you sell it, dibs please.

In all honesty, I could be persuaded

That's a sneaky way of saying "give me lots of money".

dogload

olafgarten said:

dogload said:

Gassage said:

if ever you sell it, dibs please.

In all honesty, I could be persuaded

That's a sneaky way of saying "give me lots of money".

Sorry, I actually thought I was being pretty blatant. I'll try to be less sneaky in future.

lukedlb

The Leslie has magic with all the throwing sound around. Used as one of two amp rigs, it is glorious. Alone, it just doesn't have the same effect as a larger two speaker Leslie. I'm now on my 4th Leslie and my plan was to build a 2x12 Leslie with one against the rotary baffle and the other fixed. Better would be a separate 1x12. 
So, what do I do? Use a neo ventilator v2. Incredible. Virtually identical to my Leslie 16 and a 100 other things on top. 
Sell it to gassage and use the money on a neo. 

dogload

lukedlb said:

The Leslie has magic with all the throwing sound around. Used as one of two amp rigs, it is glorious. Alone, it just doesn't have the same effect as a larger two speaker Leslie. I'm now on my 4th Leslie and my plan was to build a 2x12 Leslie with one against the rotary baffle and the other fixed. Better would be a separate 1x12. 
So, what do I do? Use a neo ventilator v2. Incredible. Virtually identical to my Leslie 16 and a 100 other things on top. 
Sell it to gassage and use the money on a neo. 

lukedlb

I'm not to certain about the high voltage anymore in the pedal. Still, pay someone or find a used one. 

jpfamps

In this style of Leslie cabinet, the switching is done by a relay that diverts mains to the slow or fast motors. The relay is mains powered and the footswitch switches the mains to energize the relay coil, thus you are switch mains on the footswitch, which is not ideal....

There are kits that allow you to use low voltage relays, and thus you will only have low voltage on your footswitch, however they are not cheap. eg Trek.

This is not a project for someone in experienced with high voltage wiring.

Incidentally no Leslie cabinet will conform to modern safety standards.

If you know what you are doing you can effect an inexpensive solution from off-the-shelf parts,.

Here's an emergency repair I did in a Leslie 122 (which uses a different switching mechanism) using parts from Maplins.

https://jpfamps.com/leslie-122-relay-repair/

It is also wise to replace the caps C5 and C6 in the Leslie unit. These are prone to shorting out and burning out the motor coil.

You should caps rated to take continuous mains voltage across them, eg Y2 caps.

dogload

Thanks @jpfamps ;
Looks like it's going to be a long wait to get anything done. There's THIS THING on Ebay but I am a bit sceptical. It seems too simple!