When is a dipole not a dipole anymore?

[Bas Horneman]

The Pied Piper has no top..

The Auris is open round the back (see picture)

http://home.planet.nl/~jmhkort/afbeeldingen/aurisklein_gespiegeld.gif

Could they still be considered dipoles though?

I am planning to build dipole Straight 8's with a Focal tc120 tweeter ...But I was thinking that if I lengthen the "wings" that I would get more bass but retain some of the advantages of a dipole.

Cheers,
Bas

PS..right now my plan was to build it like this


|____|


The width would be the same as a straight 8 but the part part behind the baffle would only be 6cm long...

 

[Nuuk]

I recently tried a deepish cowl on the rear of my open-baffles and, as expected, it did improve the bass slightly. BUT it also took away some of the di-pole 'magic'!

You are right to ask this question but probably, only experimentation will provide you with the answer when the di-pole effect is diminished.

 

[ThorstenL]

Konnichiwa,

The Auris is open round the back (see picture)

Could they still be considered dipoles though?

Yes, modified.

I am planning to build dipole Straight 8's with a Focal tc120 tweeter ...But I was thinking that if I lengthen the "wings" that I would get more bass but retain some of the advantages of a dipole.

If you put "wings" on a dipole you only extend the LF response a little but introduce a lot of added resonance from the cavities created. The Auris and it's original the Auditorium 23 Rondo use sweeping curves to minimise the resonances and thus can put substantial "wings" on that do give a substantial extension of the LF response....

Sayonara

 

[Bas Horneman]

only experimentation will provide you with the answer

Thanks Nuuk and Kuei Yang Wang..

Guess the experimentation is most important...I live 15minutes away from Jim de Kort (Auris builder) and have visited him a few times...but asking him to build my enclosures will be to xpensive..Maybe I can steal some of his ideas...build a plain one like I am planning..and later try my hand at an auris type of thing..

Maybe that won't even be necessary....since I read this bit on your site Nuuk

The big surprise is that I don't notice any reduction in the bass with the baffles compared to the ported cabinets!

Cheers,
Bas

 

[Nuuk]

Maybe that won't even be necessary....since I read this bit on your site Nuuk

Yes, but that was with the big cowl! With my larger open-baffles I am going to try some EQ first and maybe some additional woofers.

 

[sreten]

Just 2 cents worth but I can't see how angling the extremes
of a baffle back at 45 degrees would do any harm.
It would certainly stiffen the baffle somewhat.

/sreten.