On my continuing quest to build the Awesome Dolby Surround Home Theater on a Miniscule Budget, I lucked upon a mysterious set of main front speakers at the *B.E. this Sunday; with only half an hour before closing time, my spider sense told me to race to the store to intercept a potential bargain. Nothing caught my eye the first few minutes after walking through the door, but after a careful nosing through the used electronics section I noticed two nondescript, monlithic looking black columns atop a peeling vintage dresser. Speakers. Big-ass speakers.

The cabinets are finished in plain gloss black on woodgrain, with unadorned black fabric grilles (except for one small aluminum label on the lower right corner of one grille, bearing the 3D Acoustics logo); each is roughly 1 square foot in cross-section and about 2 feet high. The cabinets are very dense (using the "knock test") and nearly an inch thick judging from the depth of the wiring panel routing, with each tower weighing close to 30 pounds. The boxes are a bit worse for wear, but the sheer mass of the speakers (two-way; a single 8" woofer and dual 2" cone tweeters in a vertical "horn" arrangement) and apparent care in construction tipped me off that these might be something special. I wasn't dissuaded by the $3.00 price tag (for the pair!).

After a mad scramble to get the pair into my car's trunk (the car was parked 2 blocks away, and the B.E. was closing in 10 minutes) out of sight of thieves while I shopped for vegetables across the street, I zoomed home to examine my purchase more closely. Even if they didn't work - or sounded like utter shite - they'd make dandy end tables. I wired them up as a test, and they sound amazing: clean highs and midrange, with a tight-but-distinct low end. I can hear details on some of my favorite CD's I never was able to distinguish before.

As you can see from the yellowed, brittle label that cracked off at the slightest attempt to dislodge it from the wiring plate, this is a pretty old pair of speakers. The surrounds on the woofers are fortunately still in good condition - many loudspeakers bite the dust when the rubber or synthetic ring around the speaker cone degrades and tears, ruining the speaker's acoustic seal. But, where did these things come from?

A good long Google™-ing yielded only a scattering of references to 3D Acoustics (there was no address on the speakers, no country of manufacture, wattage ratings - nothing!). I even scoured the archives of vintage speaker forums, where I discovered a lead that 3D Acoustics was a company based out of Portsmouth, New Hampshire that reportedly produced a critically lauded early 3-piece satellite/subwoofer system circa 1980-1982, but went out of business shortly afterward. According to a number of audiophile magazine reviews of the time, the model 3D6-10B (which retailed for about $500 then) sounded almost as good as the most expensive reviewed $5000 satellite/subwoofer. High praise!

However, nowhere have I been able to find reference to the model of speaker I bought, the 3D8. The serial number is shown above; perhaps the code refers to a 1982 year of manufacture? Were these a limited run or prototype?

If anyone out in Blogland knows the story behind these, I'd be grateful for any sleuthing hints. I love these speakers, but they are indeed a mystery. But at $3.00 for the pair, I'm certainly not complaining.

• As far as I know, 3D Acoustics of Portsmouth, NH is not affiliated with the current-day company called Shanling 3D Acoustics, a high-end audio manufacturer based in China.
• www.slottweak.com has a page describing the writer's experience with the 3D6 system.
• The Classic Speaker pages forum ("Specializing in New England area manufacturers") has a post that reports the Dahlquist company purchased 3D Acoustics in the early 1980's and operated the firm for a few years.
• Regnar Hi Fidelity Inc. now sells, services and refurbishes Dahlquist Speakers.
• Steve Hoffman Forums has a thread on the 3D6B10 system, and one post (Thanks, Gardo!) features a nice 14 pp. PDF scan of the original user manual and documentation from Gardner Campbell.

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