I'll bite ! - how 'bout some open baffle line arrays ?
put these together abot a year ago, and I still enjoy them immensely . . . I'll be using them as PA speakers in May, with a pair of Karlson 15's for the lows . . . 'domestic' plans call for wall mounting in the main listening space.
Some details:
8 drivers per side - 4.5 inch full range KLH drivers which are found as fullrangers in the model 8 & 21 table radios, and also the model 14 and 19 bookshelf speakers. these drivers are also found in the KLH model 5 & 12 speakers used as midranges. 1/4 inch xmax and 60 hz F3 IIRC. paper cone, fabric surround, alnico magnets. these drivers are GIANT KILLERS.
amazing vocals, and very 'true' sound . . . in a line array they kick some serious butt.
At the top of the line array, you can see the (original) tweeters I used - Radio Shack Dual Radial horn tweeters. for PA use, these tweeters are great - a little grating for hi-fi use. For really nice sound, I bypass these, and use a pair of Radio Shack / Lineaum Dipole Ribbon Tweeters - very nice match.
Currently, the line array rolls off naturally on the top end, and I use an active crossover at 100Hz to keep the bass away. In this configuration, the arrays will handle 100 watts RMS EASILY, although 10 - 20 watts of tube power sounds better to my ears. The lows are filled in with Karlson 15's. Speaker grilles are actually Ikea wall-mount CD racks.
Since taking these pictures, I have acquired additional model 14s and 19's, so I'll be able to have all 'same drivers' - tan cones, off-white surrounds - purely cosmetic, but it'll make them look nicer. Also, it will allow me to restore my pair of KLH 14S's (shallow wall mount versions of the 19/14 bookshelf speakers).
I HIGHLY recommend everyone grab at least one pair of 14's or 19's . . . great little speakers in their own right, and if you let the drivers out of their boxes as I have, you will be pleasantly surprised :thmbsp: