"Rebuilding some round Leslie S power chambers. As bad as these things looked, the wear on the nozzles was only moderate. That is to say nozzle protrusion ranged from .010 minimum to .012 minimum. Even with all the corrosion and fouling, light sanding of the nozzles to remove any defects, chemical cleaning of the diaphragms using Prep-n-Etch (no Scotch Brite TM was harmed in the execution of this task!) reaming out of the crud from the air passageways, light cleanup of the mounting surfaces, and careful assembly in my usual way, all the 5 power chambers work quite well without having to mess with diaphragm orientation and all the other lore and superstition regarding cleaning and assembly of non-remachined S power chambers. Sometimes you get lucky. They may not hit as "hard" as freshly machined power chambers but is an example of what you can do if you want to "preserve" the sound of a "worn-in" Leslie S horn."
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