Radical

[Zilch]

Part of a project in another forum investigating the vintage EV "Baronet" mini corner horn, I closed the rear and installed "modular" JBL acoustic suspension two-ways.

Best I've been able to locate in the specs, 8" in-walls want 1.4 - 2.8 cuft loading volume, while 6.5" versions are designed for 0.7 - 1.4 cuft. Baronet is 1.5, typical bookshelf size.

In-walls are inherently engineered closed-box designs, and with applicability in HT installs, performance is garnering more attention. JBL has offerings in Pro Control series, Harman Consumer, and Synthesis product lines. These SP8s have Ti-laminate woofers and swiveling Ti-laminate tweeters.

Red is corner loaded horn, open back.

Green is closed box, in freespace, i.e., no boundaries.

Cyan is closed box in the same corner, providing more extended bass, lowered 80 Hz boom. 27 Hz - 17.5 kHz (-10 db). :thmbsup:

[Yes, I should be using sinusoidal. Working on that.... ]

[duaneage]

I'm thinking of in wall jbl with the 115 woofer from the L20T but I don't like the Qts. The control1 woofer (C1003) is a logical choice that does well with 122 - 250 cu inches but it has a wicked bad upper midrange. I had a pair of 206G drivers from the MR38 system but they also had a Qts a bit high.

With a 3.5 x 14.5 area multiplied by however high the wall is there are limits. The wallboard is far from ideal as an enclosure anyway.

I was thinking of stripping the wallboard to the floor and having a vent exit at the bottom. The wall could be 1/2 particle board that would match the drywall thickness, internal volume could be manipulated with solid fill or styrofoam blocks.

Sealed drivers are probably best but there still is the issue of the wall flex.

[Zilch]

LE8T-H sounded good, perhaps best, and I was about to try 708G and E110 next, but these, HTI8 and 128W just worked, so I avoided working through the tweeter/crossover considerations.

D208 and Altec 755A also worked horn-loaded, but there was no extended bass with either, and what was there sounded "thin," thus this closed-box sacrilege.... :)

I'd like to find some contemporary 8" or 10" drivers that'll work well using the boxes as the intended horns. What am I looking for?

[duaneage]

If your willing to go outside the JBL Altec line peerless and vifa would be my first choice, particularly the vifa p17woo series, they work in a cubic foot or so. Allegedly vifa made jbl drivers in the 90's so it's not too much of a sacrilege.

[Allanvh5150]

Excellent idea, I am doing exactly that in my home theartre room simply for the fact that it gives me more room. Main difference is that all the componants are vintage JBL. i.e. 2402's, LE5's, 117's and so on. Although I have toyed with the new stuff, it's just not the same, is it......:)