These monstrosities were built when I went off to college. They were four-way floor-standing towers built with very little knowledge, planning or testing - which is to say, they were absolutely atrocious. The impetus for these systems came from both the normal overactive hormones of a male teenager, plus having once been snubbed by a girlfriend for my tiny 6" bookshelf speakers. Hey, if I had really big speakers, maybe I'd get some respect from the opposite sex....

They began with a set of drivers for a 12" 3-way system purchased from a local car audio vendor. He had them lying around on top of a file cabinet, and let me have the set for $50. The components included a 12" paper-cone woofer with AlNiCo magnet, a 4" paper-cone midrange with square (!) magnet, and a 1" cone phenolic-ring tweeter. To these illustrious beginnings were added a pair of Motorola piezo tweeters - hot stuff!

Crossovers included caps stolen from various defunct equipment, chosen strictly for their "sonic" ability to reduce low frequencies in the drivers. Coils were hand-wound, but don't be too impressed; they were wound from 24 ga. enamel coated wire wound around old bolts, wound until they "seemed right".

Oh, yeah, great stuff.

The cabinets were 3/4" particle board with birch plywood, with dimensions approximately 15" wide by 18" deep by 4' tall. The cabinets were built as acoustic suspension, at 4.3 cu. ft, yielding a Q of about 1 for the woofers (fs 19hz, Qts 0.55, Vas 19 cu ft). Grilles were cut from particle board, and covered with brown cloth stapled in place. The midranges were built into very small (~ 1 liter) plywood cubes tacked onto the rear of the baffle.

They blasted through the first year of college, cheerfully distorting and twisting any and all musical genres. Perhaps the best comment on their sound was a simple gesture made by a party-goer when they were out in the quad: he simply tossed the remnants of the Bud in his cup onto the nearest tower.

Transformation

All good things must come to an end, and my tolerance for the God-awful sound lasted just about two semesters. After blowing out the midranges and tweeters, some real drivers were purchased. Peerless 5" midranges replaced the 4"s, and some no-name 2" dome midranges (which, surprisingly, turned up in a very-well-reviewed Jensen speaker some years later) replaced the phenolic ring tweeters. The piezos were replaced with Foster/Rank Organization ribbon tweeters.

Crossovers were custom-built by a now-defunct custom loudspeaker manufacturer, ERD, with 2nd order slopes for all drivers. Crossovers were at 1.6kHz and 5 kHz. All coils were air core 16 ga., and caps were high-voltage Polypropylene.  The woofers were re-wired separately from the remaining drivers, and the speakers were bi-amped. The electronic crossover was supplied via an Audio Control Richter Scale, set to 100 Hz, with (of course) the 15 dB boost at 35 Hz turned on. A Hafler DH-200 kit was acquired to drive the bass, and a Hafler DH101 preamp completed the electronics mods.

Naturally, with such a change in componentry & crossovers, the speakers became quite listenable. The remaining sonic blemishes were primarily the improperly-loaded woofers, and some really nasty peaks & dips in the vertical response (due of course to the large vertical separation between all the drivers on the monstrous baffle). Between the 100 WPC dedicated bass amp, and the 15 dB boost, I got quite familiar with the sound of the woofers slapping the back plate. ;-)

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