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Altec...

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nelsondog

Member
Joined 2004
I have a pair or 15" Altec 420a BiFlex woofers and a pair of 811b horns. Asking $300 for all plus shipping from BC.

Thanks for looking
 

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scottjoplin

scottjoplin

Banned
Joined 2015
That's an interesting driver, I wondered what bi-flex meant, and found this:

It has same basket as the bass drivers with 15 inch cast frame and Alnico V magnet, but the paper cone is divided into two, connected by specially selected suspension. It is like a 20 cm midrange glued to the circular remains of a bass driver. At frequencies around 100 Hz the mechanical coupling allows the surrounding bass part to start moving. Above that - the surround is too heavy and behaves like a frame. Very clever, inn'it? I think someone called this a "mechanical crossover".
 
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