Explanation for horizontal beamwidth of JBL 3252(N) ?

I have heard of it before but hadn't considered it, mainly due to the 'ribs' seen on the cones, that are meant to improve rigidity and thereby a achieve 'more pistonic' motion (attachment from JBL Tech Note Vol1, No. 3A).
Hmm, a bit history WRT Lansing Manufacturing vs Altec meant that when JBL went solo they needed a new woofer that mimic'd the performance of W.E./Altec's curvilinear cone, so created a ribbed conical diaphragm that flexed to mimic it and as of 1986 was still flexing near enough identically to the pioneer's 'tune' per Altec's comparison (see attached, scroll down to 15").

Has JBL fundamentally changed their woofer design? No clue, but history has shown that manufacturers don't 'fix what ain't broke' unless it's a true improvement in performance/cost ratio, hence my 'biflex' assumption, another of the pioneer's proven designs still used nowadays, i.e. this appears to me to be a driver that flexes the flexed. ;)
 

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This is a very low priced speaker sold under the JBL label, as far as I understand not a high fidelity product, but for basic public cinema needs. It has a very high sound pressure level and may sacrifice some sound quality for it.
The Harman brand has a history of cutting cost's to compete with others. Today a speaker wearing the "JBL" label may use Brasilian Selenium chassis for example. Selenium being on the high quality side of the chassis used in JBL products. There are far worse.
The competition in pro, just like Hifi chassis, has grown strong with the centuries. JBL speaker under the Harman brand, in my opinion, are nothing outstanding any more. You have to spend serious money to get the" JBL Experience" of the past, at least . This is the price you pay for modern marketing and competing in all price ranges.
 
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Your attachment is incorrect, a curvilinear profile means just that, curved. ;)
Small problem here with the curvilinear page. I shall, of course, try a little later, but are you sure it's working ?

1692767874943.png


JBL went solo ... mimic'd the performance of W.E./Altec's curvilinear cone, so created a ribbed conical diaphragm that flexed ...see attached, scroll down to 15".
So you say that the ribs still permit flexing of the cone and JBL's curvilinear (shallow according to Altec) doesn't do much to the beamwidth beyond what it originally is.
Has JBL fundamentally changed their woofer design? No clue, but history has shown that manufacturers don't 'fix what ain't broke' unless it's a true improvement in performance/cost ratio, hence my 'biflex' assumption, another of the pioneer's proven designs still used nowadays, i.e. this appears to me to be a driver that flexes the flexed. ;)
Yes and BTW, even I'm alright with the bi-flex thing.

http://www.voiceofthetheatre.com/images/412C.415C.1.jpg