array or sweet sixteen?

[zobsky]

hi zobsky

any threads to point me to for a read? yes, my line array is open on the back, thats the way i like it for clarity in the midrange, plus dipolar radiation pattern
i have been experimenting with piezo tweeter in the back, since only midranges are dipoles, tweeters are aura line source with magnets on the back
adding piezo tweeter helped
i hear more hights, cleaner trebles upfront, do not know why
spaciousness with piezo has improved, generaly was very good already

i am very happy with these speakers, very dynamic, low distortion, flat response, high efficiency...all the advantages of line array

I have an open baffle array thread on diyaudio.com / loudspeakers (not much there yet, .. still very much a work in progress).

For open baffle specific info, there is a forum devoted to this on audiocircle.com.

Regarding the piezeo, ... my SWAGs (scientific wild a** guesses) are

1.the ribbon line MIGHT be rolling off a bit at the top due to comb filtering and the piezo is adding that back.

AND / OR

2. rear firing tweeters generally help with a sense of "ambience". Maybe that is what you are hearing.

AND/OR

3.Have you matched the efficiencies of your tweeters and your mids? It could be that the tweeter line is less efficient than the mid-line . In any case, the shorter tweeter line is going to get into far field earlier than the mid line. As a result, its SPL will drop off faster with distance .

Of course, you're enjoying them, which is important. The above was just my $0.03 worth of dumb observations.

 

[kenpeter]

Can somone repost PDF of the original article? The earlier link in this thread appears dead.

 

[planet10]

Link fixed.

dave

 

[CLS]

I'm late to this thread.

The photos of the sweet sixteen made me think of this: http://www.diyaudio.com/forums/multi-way/90804-large-midrange-ob-scott-g-40.html#post1953221

The 'phase array' in the post above utilizes a shunt cap on the 'outer' drivers. So those outer drivers only play in lower part of the range, while inner drivers cover larger range (extend higher). And a 'proper' polar response can be tuned by the size of array and the frequency ranges of those inner/outer 'rings'.

I thought to myself, that sweet sixteen might also be wired (and shunted) this way and yield a better result...

Anyone? 🙂

 

[Paul W]

Depending on what you are trying to accomplish, yes. Also, to help reduce floor and/or ceiling bounce, you could wire sixteen drivers for an asymmetric HxV pattern with the outer 8 drivers rolled off and the center 8 drivers running higher...same for 4Hx3W etc. The concept can also be used to help manage the polar pattern of line arrays.