Questions about planars, line arrays, and B3S's

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So, I have 12 of these Hi-Vi B3Ss here that I purchased for use in a Christmas present project for my father-in-law. I decided, to instead, give him my small bookshelf 2-ways (using the DC28 and the RS125) after a crossover rework that seemed to really do the speakers justice. Only thing is, those bookshelves served as my center channel.

Now I need a center channel.

Being impressed with the center channel that Darren @ PE created, I figured I might have the perfect solution to my quandry. After reading the article on non-domes over at www.zaphaudio.com ;I purchased a Neo3PDR to serve as the tweeter.

I've modeled different wiring and crossover schemes, and have decided on a series-parallel (for the Hi-Vi's) wiring scheme (6 ohms) with a 2 way crossover. I wanted to try a 2.5-way setup, with 4 of the innermost drivers (wired in an 8-ohm configuration) stepping in at 2500Hz, but the final impedance was quite low with the outer drivers in a 4-ohm series-parallel wiring scheme.
The enclosure will be 50.5" wide, 12" deep, and tall enough to accomodate the Neo's waveguide faceplate (dimensions match my Mitsu's top panel).

Should I consider this setup a type of horizontal line array? Will the dispersion characteristics of the Neo change the need for center-to-center placement? Should I tune the enclosure for an F3 of 70Hz (when taking into account what was said at http://zaphaudio.com/audio-speaker18.html about the B3S)? Does this sound plain stupid? Thanks.

[owdi]

IMO, stay away from venting. Three reasons:

1. Try modeling the response of the B3S in a vented enclosure. You will find it looks bad, with a dip and a peak. After you factor in the highpass crossover, you will see that it hardly makes a difference in bass response.

2. Whenever you vent a full range driver you have the serious problem of sound other than bass escaping the vent. The most serious problem will be a 24db peak at the frequency whos quarter wavelength is the lenght of the vent (I think, not 100% sure, you should verify this).

3. The B3S, just like any other speaker, will have problems when playing at fs (will be around 110hz). You will have energy problems (harmonic distortion, low decay). Since you want to cross the speaker above fs to minimize these problems, no point in trying to extend the response below that point.

Dan

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Thanks alot! I appreciate your insight, as I hadn't thought of that and it didn't model into the frequency response I had plotted.