Dipole tweeters

[firestorm]

Hi,
I'm looking for suggestions for dipole tweeters, the Linaeums are thin on the ground and the Beyma TPL-150 is way above my budget.

Anyone used Vifa D25AG77 before ?

Anyone know if I can get away with tweeters back to back?

Cheers

Happy New Year !

[ScottG]

Fast, fun, Inexpensive OB project

Mounting driver's back to back doesn't technically result in a dipole speaker because of the separation distance between the two drivers. Of course real-world it might not matter much, or perhaps more correctly the baffle shape/size you use will likely have a much greater impact on the results then a minute difference in distance (..assuming it actually is quit small).

[firestorm]

Hi Scott,
thanks for the link, very informative !

Happy New Year !

[tinitus]

Tangband W2-800SL

With 18ohm series resistor and 3.3-4.2uf it sounds quite nice
Theres indication that a paralel 15ohm will improve
And maybe a paralel inductor and resistor
But at the moment it plays with just the series components
I know, 18ohm in series seems strange, but it really works
Other values may be better, I just threw it together in an hour
Been listening to it fore a week, and nothing to complain about
At this price I doubt you will find any better

[cuibono]

I would love to find more (small) affordable dipole tweeters.

I currently use the Neo3PDR, and have no complaints. It has excellent polar response, and hasn't blown while listening loud (although I'm still waiting for PE to get them back in stock since blowing them when switching amps live - if you're going active with your crossover, don't be like me, use protection!). They are affordable too.

Some of the AMTs look really nice, but are way too expensive.

I experimented with small, back to back tweeters here. They worked surprisingly badly.

[LineSource]

A few dipole speakers are taking the rear cover off of compression drivers to generate dipole radiation. Coaxial speakers with integrated compression drivers are also using the open dome back for dipole radiation. Few seem to be putting a horn on both the front and rear of the dipole compression driver

Has anyone experimented with using a compression driver with the rear cover removed for dipole operation? Are any specific compression drivers constructed to operate safely without their rear cover?

[Jonasz]

I'm also interested in this topic. Having used the Neo3PDR with great results I want a tweeter that can be crossed at 1kHz or lower. I've been thinking about the M&D DM-4 driver wich is available at $250 per pair. I know about Zaph's measurements and I don't think they look as bad as he thinks they do. It's really just a little dampening of the top octave and maybe the resonanse needed. I've listened to the M&D speakers and I think the upper mid and treble are awesome so I'm seriously thinking about getting a pair...

[firestorm]

Gainphile has had mixed results with soft domes back-to-back, so I might bite the bullet and jump to ribbons like the Neo3, where ScottG has provided a link to a very interesting article about adding a horn/waveguide to the Neo 3.

The B&G Neo3/8 look like possible candidates, the Founteks are easier to source, but are not dipole or easily converted into dipoles.

Whats the best place to get the B&G's ?

[el`Ol]

Originally Posted by cuibono

Some of the AMTs look really nice, but are way too expensive.

There is a Harwood AMT for just 200 € that got an excellent test in the latest Hobby Hifi.

[Jonasz]

Neo3 aren't ribbons but magnetostats. If your crossover is at 2kHz or over Neo3PDR is all you need IMHO. Parts Express sells them and I'm sure there's sources for them in Europe too.