This is a picture from when building the speaker. The building process lasted for over 2 years!
Here you can see the 1.5 mm magnet strip which also together with doublesided foam tape acts as 2.5 mm stator/membrane distances. The magnet tape is special as it is manufactured and sold in two rolls, magnetized in opposit directions. This magnet tape is also totally nonconductive!
This is the finished speaker with its stainless steel frame. As you probably can see, the
membrane is divided into four different sized fields.
This is the membrane resonance frequency adjuster device. I usally adjust it to 48-50 Hz.
These speakers are not connected to mains wall output, instead the high voltage ladder is connected to the driver transformer output via resistors, so the membrane is biased only when you use the speaker, preventing dust collection. I'm very happy with this arrangement and will never connect my future speaker to the mains!
Dust collection is not a problem here, just separate the stators and start cleaning!
The stators snaps together with a loud snapping sound, clamping the film with a very consistent and accurate distance.
Here you can see the stator connector and the plexi bits that the one millimeter thick stators rest upon. The bias voltage is simply connected to the stainless steel frame via 50 Mohm resistors, totally harmless but not a very good idea for comercial use. It certainly keeps greasy fingers and cats away!
You can just pull the stators apart and clean the film or apply a new coating.
Here you can see that packing tape is mounted along the sides to prevent wrinkles caused by stator weight. It might also prevent high frequencies to reflect against the metal frame.
The stators consists of one millimeter "Rilan" powdercoated alu sheets.
The stainless steel frame also act as bias connector.