Help Diagnosing Leslie 145 Modification

[storkrecords]

Hello-

I recently purchased my second Leslie 145. The first is in the process of being restored, lets say she has a lot of character. While cleaning the first another popped up locally. The second is in fantastic shape so I scooped her up. The drawback is that she's originally from England with 240 power. Complete disclaimer: I'm not only a newbie, but I'm also electronically challenged. The second Leslie also has some type of modification going on. It looks like they ran wiring from the amp to a 1/4, power, and 4 pin connector on the outside panel. So I have 2 questions.

1. Is there any reason I cannot take the amp from my first 145 (USA power) and place it into the second 145, fire her up and go?
2. What would you suggest I do to the amp in the second 145 to make her useable here in the US? and what about this modification?

OK, I guess that's 3 questions. I'll attach some pictures of the second amp with the modifications. Thanks for any assistance you may be able to offer.

-Ed

[Wes]

Well, that's creative.

You should be able to use your US amp in the English Leslie, assuming the motors are stock. But you will have to swap across your fast motor pulleys as well to get the Leslie spinning at the right speed.

To convert the English amp, you will need to change the relay to a 120V relay, and either replace the power transformer or augment it with a step-down transformer.

[storkrecords]

Thanks Wes,

Yes, the motors I believe are stock. They're 117 50/60. So is the process of "swap across fast motor pulleys" challenging? Is that something I can find a video tutorial for?

-Ed

[Goff]

Thanks Wes,

Yes, the motors I believe are stock. They're 117 50/60. So is the process of "swap across fast motor pulleys" challenging? Is that something I can find a video tutorial for?

-Ed

If the motors have the 50hz pulleys for the 50hz AC area like the UK, the 60hz pulleys are available on the Trek II site.

It's just a matter of unscrewing the 50hz ones and replacing them with the 60hz pulleys available from Trek II.

https://trekii.com/products/leslie-speaker-accessories/leslie-pulleys-60hz.html

Don't know of any videos on the subject but if you can change a light bulb, these pulleys should be as easy, if the screws on your pulley motors are not rusted shut. It should be intuitive.

[Jyvoipabo]

Hello,

The owner's manual of the 145...247 gives the differences between the UK 230V / 50Hz and the US 117V / 60Hz models.
Some components are 50 / 60Hz.
But what works in 50Hz also works in 60Hz but the reverse is not true : It grunts.

The amphenol plug has been doubled with the white-threaded wiring. With 3 bases.
-EU base = Power.
-Jack = Sound.
-4pins Amphenol = Speed control.
As the original plug is still present, you can remove all that.

JP

[enor]

Here's a thought:

The 240V Leslies have a power transformer with two primary taps. The 240V one, and an additional 120V tap for powering the motors.
It seems to me that it should be entirely possible to just rewire the amp so as to feed the transformer to the "motor tap" instead of the "main tap"; and therefore keep the Euro transformer.

If anyone can think of a reason why this wouldn't be feasible, speak up :)

[geoffbrown]

If I was going to adopt your suggestion I would measure the current draw before and after as this may overload the primary winding of the PT also monitor the temperature of the PT,otherwise it's worth a try

[enor]

Yes I agree. However - considering that the motor current no longer will have to load down the transformer (they can be wired directly to mains instead of via the transformer), that must free up some headroom. Without having tried, I'd be surprised if it didn't work just dandy.

[storkrecords]

Thanks so much everyone. I really appreciate all the input. I also appreciate working with a newbie. One must go through elementary school first, right.

Would love to know if what Enor mentions will work in having someone rewire the feed to the 120V motor tap using the 240V transformer. Also, I didn't initially mention that it came with this wiring harness. Do you think this was used in US with this modification? I'm trying to wrap my head around why they would do this?

[Goff]

Thanks so much everyone. I really appreciate all the input. I also appreciate working with a newbie. One must go through elementary school first, right.

Would love to know if what Enor mentions will work in having someone rewire the feed to the 120V motor tap using the 240V transformer. Also, I didn't initially mention that it came with this wiring harness. Do you think this was used in US with this modification? I'm trying to wrap my head around why they would do this?

That's a power cable with a plug for a non-U.S. power grid for UK.


If this were my gear, I would get a U.S. version amp and sell the UK amp to someone who can use it.

We might want to consider that in modifying these units, the next person, such as yourself, now has to figure out what was done to it and how to retro the circuitry. Many times we find gear that has been changed and without any clues as to how to fix it. Although this worked for the previous owner, now the problem that they created has fallen onto your lap. Rather than perpetuate the cycle, going with something that is original and of use in the U.S. would resolve any mod issues plus it would retain the value of the unit. Especially if the Leslie is now a complete working unit.

You may get some ideas on how to retrofit your 240 volt amp. But keep in mind, you will always have to refer to someone who is a wizard (with Leslie amps) to fix any problems that crop up in the future, where if the amp was original to a schematic, most competent electronics guys can trace problems. This would be a project for someone with Leslie amp repair experience and not for someone who has no electronics knowledge.

As the saying goes, nothing comes free and we get what we pay for.:->

[storkrecords]

Goff, Agreed. I picked up the 145 at a good price. The cabinet and components are in great condition, so I'm definitely not apposed to doing what is right to preserve the quality and condition of this 145. I'm going swap the amp from my other 145 for now to make sure everything works. I'll begin asking around to see if anyone has interest in the UK amp. Thanks -Ed

[Goff]

Goff, Agreed. I picked up the 145 at a good price. The cabinet and components are in great condition, so I'm definitely not apposed to doing what is right to preserve the quality and condition of this 145. I'm going swap the amp from my other 145 for now to make sure everything works. I'll begin asking around to see if anyone has interest in the UK amp. Thanks -Ed

Yup, Ed. I figured you got a good deal on the cabinet which is worth more than you paid along with speakers, motors and the crossover. You're still ahead in that respect and have rescued those parts no matter from a worse fate. Moving forward, a better path is now yours.:-)