Five Tweeters in a Row

[raypalmer]

So I've been reading the series vs. parallel thread and a few other related posts and I have to ask about lining up tweeters. Not like ribbons vertically aligned in an array but domes horizontally. I recall seeing speakers in a shop once, they were McIntosh's. The sales rep said the trick was that one of the tweeters was wired out of phase...

Obviously the five tweeters together can handle more power, which would explain why McIntosh with their absurdly powerful amps would want to build their speakers that way. But are there any sonic benefits? How does it affect off-axis performance?

I'm almost tempted to buy five of these to see what it's like.

Would that be foolish?

Here is a pic of something like the speakers I saw:

[Pano]

Interesting concept. Wonder how they make it work?

Funny, but at first glance it reminded me of this:

[Godzilla]

McIntosh makes some funny looking speakers. They actually have one that looks like that alien pic...

McIntosh | XRT2K

[jrenkin]

Yes, and they sound best in the halls of the castle Aaaarrrrrgghhhh.....

[bjorno]

Originally Posted by raypalmer

..Obviously the five tweeters together can handle more power, which would explain why McIntosh with their absurdly powerful amps would want to build their speakers that way. But are there any sonic benefits? How does it affect off-axis performance?...Would that be foolish?...

Hi,

More Jokes:

Five tweeters in a horizontal row,one reverse poled makes a short Bessel array power weighted( 1,2,2,-2,1) with the vertical power polar almost equal the horizontal.

If you hook up 5 Dayton's horizontally and sit at ~20 times the array length
the horizontal azimuth will appear with a MMA (Minimum Audible Angle) like for a single tweeter with a ~20 cm wide baffle.

IMO this work very well but only for tweeters due to phase at XO: above ~1.2 kHz where the left stereo right phase ambiguity starts to introduce amplitude ripple due to ear to ear distance (here~0.145m).

A couple of years ago I made a test with an improved horizontal Bessel array
using 7 drivers that IME had a very good on and off axis response, sharp localization when used as a center tweeter in a Ht setup.

See the Pictures:

b

[Don Hills]

Originally Posted by raypalmer

So I've been reading the series vs. parallel thread and a few other related posts and I have to ask about lining up tweeters. Not like ribbons vertically aligned in an array but domes horizontally. I recall seeing speakers in a shop once, they were McIntosh's. The sales rep said the trick was that one of the tweeters was wired out of phase...

This is called a "Bessel array". A Google search will find you information about them. Their main advantage is that they provide an even dispersion with freedom from "comb effects". The disadvantages are that you need to be a long way away from them to get the best result, and they are not as efficient as one would think. (Measure the width of the array. Your listening distance needs to be at least 10 times that.) They also have unusual phase characteristics, making it difficult to integrate them with other drivers in a multi-way speaker.

[PeteMcK]

A Paul Kemble web page - speaker bessel arrays.