Leslie 147 cabinets. posted by Rob S...

Where I work, we have 4 of the 147 Leslie cabinets. We also have several others, but this is about the 147.

One of the original horns started to rub. I took it apart, and found our that the voice coil was out of round.

I found a place that sold the replacement diaphragm called the Tone wheel general hospital. And for $66.00, you get the diaphragm and gaskets.

When I got it in today, I was hoping that it would have the installation instructions with it. No such luck.

The diaphragm comes completely disassembled. (I should have taken pictures as I did this) So, you just have a voice coil that has two long leads coming off of it. Soldered to nothing. 6 - 1/32" gaskets. 2 - 1/8" gaskets. And that's it.

I called up Hammond Leslie to ask if they had the installation instructions online. They said that they have not been involved in the reconing or replacing diaphragms since the 70's. So, there is no way that they would be able to help me.

I called back over to Tone wheel general hospital, and Rick over there pretty much said the same. Even the guy that he had that did do around 70 or more for him, told him to never send another one his way.

We have a Hammond organ center just South of Philly, so I called their repair guy Bill. And even he told me that he had never replaced the diaphragm. He has only refitted the horn with a retro kit from EV.

At this point I talked to my boss and told him that I was striking out on how to install this diaphragm. He said that since the kit only coast $66.00, and that the retro kit is around $167.00, to go ahead and try to figuare out how to do this on my own. If I F up, then I F up.

Well, I managed to install it, and I figured that I should share what I found out for anyone else that should encounter this issue.

Here is a list of tools that are needed:
Epoxy. (For the voice coil leads)
#2 flat screw driver
#2 Phillips screw driver
A Hole punch
Solder and Soldering Iron
A tone generator that can produce 1Khz
And a sharpie

The first thing that you are going to do is, undo the three #2 Phillips screws that are on the bottom of the rotating horn. This will drop the whole driver assemble from the cabinet. (Don't forget to remove the two female spade leads that are one the driver.)

After removing the driver from the cabinet, you will have three #2 flat head screws that hold the bearing plate to the driver. Remove the three screws, and make sure not to loose the three spacers that are underneath.

Now you will have 6 #2 Phillips screws exposed. Two of which will be longer then the other four. The two longer ones will be in the magnet that is shaped like a "U". It is important that they make their way back to these spots.

Remove the 6 Phillips screws that hold the diaphragm cover. The magnet will then be able to be removed from the diaphragm. The diaphragm it's self, will not be able to be removed just yet. That some tape that will not leave any residue on the magnet, and cover the air gap so that no dirt can fall into it.

No the top of the diaphragm cover, there will be two spots that the wire leads drop into. At the bottom of the wire leads that go to the voice coil, take your soldering iron, and remove the solder. Be careful! Since the surround in that area is plastic. You do not want your soldering iron to melt any of that plastic. So move quickly!

After the voice coil leads have been unsoldered, you can now remove the voice coil. You will have noticed that there are two sets of gaskets. Some below, and one above the diaphragm. Out of the new gasket kit, match up the thickness with the new ones to the old.

Now, for the fun parts..........

Place the new diaphragm over the old one. CAREFULLY!!!! Match the orientation of the voice coil leads of both. Now take your Sharpie and trace the bolt holes onto the new gasket. As the holes that are in the new one, will not match the old.

After you have them traced, use the hole punch to cut out your new bolt holes. If it is a little larger then the original, that's fine. This will give you a little room to try and center the diaphragm.

Now mix your epoxy. And pass the leads of the new voice coil through the holes of the new diaphragm. The old holes that are preexisting. And epoxy the leads to the diaphragm as close as you can to the preexisting holes as possible. Just a little dab will do. Your only trying to keep the leads from rattling around on the new diaphragm.

Place the new gasket under the diaphragm, and pass the voice coil leads through the plastic cover to the wire leads. In the same orientation that the old one came out. Resolder the leads back to the cover as tight as you can.Once the leads are resoldered, snipe off the excesses.

Now take the new gaskets that are of 1/32" in thickness, and match the old thickness. And place the gaskets on top of the new diaphragm. Pay attention to the orientation of these gaskets. They should line up on the new voice coil leads, and the bolt holes. You may have to flip them upside down to get them to match.

Remove the tape from the air gap of the magnet. And Very VERY CAREFULLY! place the magnet back over the top of the new diaphragm.

Flip the driver over, and replace the 6 #2 Phillip screws. Make sure the the two long ones go back into the "U" magnet. Do not tighten the screws yet. Connect the driver to an amp, and turn up a 1 Khz tone. Remember, this is only a 40 watt driver. So do not over drive the 1k tone.

Carefully listen to the driver. Make sure that you do not hear any rubbing. If you do, slide the diaphragm slowly and gently around until the rub goes away. If the rub does not go away, you may need to add another 1/32" gasket. Or even remove one. It's not an exact science from what I can tell.

Once the rub has been removed, tighten the 6 #2 Phillips screws on the cover. Reinstall the bearing plate, with the spacers underneath. And mount the driver back into the cabinet.

This should give you another 20 years or so of listening enjoyment!