PMC Factory Tour, Part II. Hifi Trio Visits PMC!

We continue with the PMC factory tour now, by visiting the area where the magical 3 inch mid range dome driver is assembled. Keith Tonge continues to be our tour guide.


Note the finished 3 inch mid range dome driver on the bottom right corner, laid out all over the table are the various pieces that make up the over sized magnet structure of the driver.



Keith show us the reverse side of the partially assembled dome, which we'll see how this part is formed later.



Keith shows the front side of the dome, which is hand coated to ensure uniformity of the coated surface.



This is the first step of the magnet assembly.



Followed by another additional copper cap.

Topped with a piece of precision die cut high density foam, which acts as the stop bumper to prevent the voice coil from over excursion. Keith says that since the foam is eternally sealed inside the cap and dome structure of the driver, it will not deteriorate with time and age.



See, another aluminium cap seals the foam.

 

Another copper cap and magnet structure is added to the assembly. The whole assembly will be put in to an electro magnetic chamber to get magnetised.

 

This is the voice coil winding machine, with 2 pieces of finished coil on the right hand side.



A closer look at the voice coil winding process. Note how fragile the copper wire is?

Maria personally coats every dome, winds every voice coil, and seen here attaching the coil ends to the dome. 



Marquette hand solders all the passive x-over components and PMC's internal electronics such as active x-over and plate amps for powered speakers.

 

The finished boards are then tested to meet specifications. On test here is a BB5-XBD x-over board.

 

Finished plate amp modules, completed testing procedure, and awaiting further assembly.


From here onwards, we will move towards the final speaker assembly area. Stay tuned for the final part of our PMC factory tour!