Question to inventors using JBL drivers

[clwinbe]

Hey folks, hope your all safe....

ive put a very nice little surround system with blond JBL L80T3 up front, matching L20T3 for rear and a Citation 7.4 sub. But what to do for a center channel? I would think two 115h-1 woofers and a 035ti tweeter would make for a great center channel. Has anyone out there tried this type of thing?

[Mr. Widget]

As a general rule the twin woofer surrounding a tweeter designs are marketing driven and are not good designs. A pair of small woofers flanking a mid and tweeter are much better from a design standpoint. The issue is that a pair of small woofers with a crossover to a typical tweeter has very bad frequency response lobing in the horizontal plane.


Widget

[HCSGuy]

When I first started selling car audio to put myself through college, the Circuit City I worked at had t3's, but I don't remember ever seeing center channel speakers, matching or otherwise (original Dolby surround was just a pair of surround speakers added to your front two, there was no center speaker until Dolby Pro-Logic at the end of the 80's. Fosgate may have used one sooner, but I wasn't at that end of the market). When the L series replaced the t3's, and I moved to home audio, they still didn't have a center channel speaker, so we would break up a pair of L1's and sell one of them as a vertical center speaker, which you could certainly do with a L20t3.

The early center speakers, which were as you describe, just a tweeter stuck between two woofers, had problems with frequency response lobing, where they would sound different to the person sitting off to the side than the speaker did to the person sitting head on. Just like your L80t3's sound different if you're standing versus sitting, stick that speaker on it's side and standing/sitting will get much better, but sitting in different seats will get worse. Sorry if this description isn't well written:)

Anyway, the fix to this is to have as much of the frequency range as possible done by vertically oriented speakers. Better center speakers starting in the mid 90's have a tweeter and 4" or so midrange vertical in the center of the cabinet, flanked by a pair of 6 1/2" or so woofers. You could do something like this, just adding a 104H-2 mid. This would also let you copy the top half of your L80T3 crossover. You would end up with something that looks like a JBL PC600 (you can decide if you like the angled woofers or not):

88152

edit: Kudos to Widget for banging out a reply while I was still typing:)