What are Bipolar, Dipolar, and front-ported? (1 Viewer)

[Wes C]

Im new to home theaters and I have been reading this site to increase my knowledge. Could someone tell me what these 3 things mean and the differences they make. Thanks!

 

[Drew Eckhardt]

A bipolar speaker has drivers which radiate in-phase on opposing surfaces. Commercial producers include Definitive and Mirage.

Dipoles have surfaces radiating 180 degres out of phase. This may be accomplished with single diapraghm (electrostatic or magneplanar, as in Martin Logan/Final or Apogee/Magnepan respectively) or dynamic drivers (this is the case for THX surrounds).

Front ported speakers have a port on the front. The excuse given is that you "could" place them in a book shelf or something without obstructing it, although this will ruin the sound anyways so it's not a real issue.

 

[Wes C]

Can you dumb down bipolar and dipolar for me?

 

[Ryan T]

Wes

Bipolar speakers have drivers(speakers) on the front and back of the encloser(or angled on the right and left sides). with bipolar speakers all the drivers are wired the same way. Dipolar speakers are setup just like bipolars except that the back drivers are wired out of phase meaning the are wired backwards. someone please correct me if i'm wrong.

Ryan

 

[Ryan Schnacke]

So if you think of "in" as "towards the inside of the box" and you think of "out" as "towards the outside of the box" then they work like this:

With a bipole speaker both drivers move "in" at the same time and then they move "out" at the same time.

With a dipole speaker one driver will be moving "in" while the other is moving "out". And then they'll both change directions so that the first is moving "out" while the second is moving "in".

 

[George Martin]

I have a question in reguards to this topic.

Which is better for side surround speakers in a 7.1 set up that has direct radiating rear surrounds?