Spectrum Audio 108cd loudspeaker

Tricker tweets? I know, Halloween has already come and gone, but I just had to use that because this little speaker has a trick about its tweeter. The Spectrum Audio 108cd is constructed of ¾" MDF for the baffle and ½" MDF for the sides, with a very–high-quality black ash vinyl covering all the way around. (A brown ash finish is also available.) Rapping on the cabinet results in a hollow bonk, rather than a solid thud. All the corners are squared—no radiused edges, which is probably one of the things that helps them keep the price down. The quality of workmanship isn't up to the fine furniture level of the Phase Technology PC80 II that I also review in this issue, but considering the price, it's more than acceptable—I had to ask if the covering was veneer or vinyl. The removable black grille covers the whole front of the speaker. The company name appears on a tag on the grille, but oddly enough, the model number is nowhere to be found—not even on the back (footnote 1).

Speaking of the back, all you'll find back there are the recessed, angled, gold-plated five-way binding posts. Inside is what Spectrum refers to as their critically aligned, phase-coherent, directional crossover. The first two parts of that description sound familiar, but "directional" didn't—so I asked. It means that they assemble each component, including hookup wire, with the optimal directionality.

Up front there's a port on top with the two drivers just below. The tweeter (a ¾" dome) has its center almost directly in front of the top edge of the woofer's dustcap, the woofer itself being an 8" long-throw model. "What?" you're saying, "How can that be? You mean the tweeter is actually inside the woofer? But offset, not a coaxial design?" You're half right—it's not a coaxial design, in the usual sense of the term, but the folks at Spectrum Audio refer to it as a coaxial mounting system. The tweeter is suspended in front of the woofer by four Neoprene bands, one at each corner attached to four pegs situated around the woofer. Amazing? Strange? Unique? You bet!

Tap the tweeter, and it bobs like the head of one of those spring-necked dolls you see in the back window of the '62 Chevy in front of you at the drive-thru. Even more amazing, the leads to the tweeter come right through the woofer cone! There's a hole in the cone for each, and a dab of sealant to close up the hole. The idea here, according to Spectrum, is that this mounting effectively decouples the tweeter from the enclosure, which is desirable because cabinet vibrations can interfere directly with the tweeter's operation. Also, the near-coaxial mounting provides something very close to a point-source; staggering the mounting, as Spectrum does, is said to prevent some of the cancellation problems that arise with true coaxial systems. Does it work? Funny you should ask...

108cd Sound
I auditioned the 108cds mostly with the stands in the same position as for the Phase Technology PC80 IIs, but I let the 108cds fire straight ahead—no toe-in. I auditioned these guys using primarily the following eight recordings: "Mississippi Summer" from Freedom and Rain (LP, Cooking Vinyl Cook 031) by June Tabor and the Oyster Band; "Ballad of the Sun and the Moon" and "Try, Try, Try" from Alejandro Escovedo's Thirteen Years (Watermelon WMCD-1017); "Ever Since the World Ended," from Mose Allison's album of the same name (CD, Blue Note CDP 7 48015 2); Rachmaninoff's Cello Sonata in g, Op.19 (CD, Bainbridge BCD6272) with cellist Stephen Kates; "Falling Elevators" from MC 900 Ft Jesus' Welcome to My Dream (CD, I.R.S. X21S-13114); "One for my Baby (And One More for the Road)" from Billie Holiday's Songs for Distingu;ae Lovers (Classic/Verve LP MG VS-6021); and "Invitation to the Blues" from the Holly Cole Trio's Temptation (Metro Blue CD CDP 8 31653 2).

The one word that sums up the 108cds is "aggressive." These aren't polite, laid-back speakers—no, they're brash and bold, and seem to be playing loudly at any level. Imaging-wise, the Spectrums performed okay when there wasn't too much happening all at once. In places during Alejandro Escovedo's "Try, Try, Try," where there are a handful of little things going on, those pings and dings stood out pretty well, as they should. However, as soon as the rest of the band kicked in, things thickened and blended into more of a flattened sonic blob. As with the PC80 IIs, I didn't get much sense of depth; on a system capable of delivering it, the Billie Holiday track gives good layering of the soundstage, but things were in the 2D realm with the 108cds. That bizarre MC 900 Ft Jesus track worked well at putting most of the sound to the outside of the speakers, but they weren't arrayed as well along the sidewalls, instead being more clumped right next to the speakers.

As long as the music stayed in a range from the upper bass through the lower midrange (for example, on some significant chunks of the Rachmaninoff cello sonata) the 108cds sang the tune faithfully. From midbass on down, the 108cds seemed to roll off steadily, leaving the lowest bass notes weakened (compared to the Phase Technology PC80 II), yet the pitch definition was quite good. That opening synth bass thang on the MC 900 Ft Jesus track had much better pitch definition than with the PC80 IIs, but not as much power, and the opening acoustic bass on the Holly Cole track seemed radically lower in level, allowing me to avoid dislocating my jaw for a second time and to follow the notes, even if I had to turn up my hearing aid to hear them (footnote 2).

The thing that outright bugged me about the 108cds was that there seemed to be just too much high-frequency information. Cymbals sounded brittle and brash, sssssibilants really sssssizzzzzled, and the saxes on the Mose Allison cut had a sharp edge riding on top of their sounds. The saxes also didn't have quite enough midrange body; this was evident from the sound of Mose's and Billie Holiday's voices as well.

This excess HF energy contributed to a loss of resolution and imaging, as individual instruments seemed to be surrounded by a mist of trebly fuzz. As reported above, I pointed the speakers straight ahead instead of toeing them in, in an attempt to reduce the amount of HF energy reaching my listening position. I also kept the grilles on. I tried the 108cds briefly with the grilles off, and with them toed-in, but those setups were too much for me. Firing straight ahead and leaving the grilles on didn't cure the problem, but it did help.

As with real estate, with speakers the three most important things are location, location, and location. Realizing that the 108cds might want a little rear-wall reinforcement to help out that rolled-off bass response, I moved them back, settling at about 40" from the back wall. Yes indeedy, now the bass was fuller, went lower, and still had more-than-decent pitch differentiation. The opening bass on the Holly Cole cut went from wimpy to solid and powerful. Mose's voice and piano had more body (which was welcomed), and, happily enough, the imaging even seemed to be more tightly focused (not what you'd expect from moving speakers toward the back wall). The excess HF was still in excess, but managed to call a little less attention to itself, thanks to the added warmth.

The 108cd will handle some power and play loud, but unless it's a particularly dark recording, that HF energy gets to be too much—for me, anyway. Its high sensitivity will allow it to mate well with low-powered amplification, too.

Lonnie wraps up
If these speakers were wines, the Phase Technology PC80 II Compact Monitor would be a good midpriced Cabernet Sauvignon: smooth, with some subtle flaws but no fatal ones. The Spectrum 108cd would be more like a rustic Barbera: earthy, assertive, with some unusual characteristics that would turn some people off, but which others might find attractive.

If everything sounds kinda dull to you, you might like them. The 108cds do offer good bass definition, and some decent extension if you don't put them too far out into the room. And man, they're cheap! Might be perfect for the rec room, or for that low-budget Home Theater setup, but for your main setup...? I dunno. Not mine, anyway, but your tastes may differ. Give 'em a taste...I mean, listen.

Footnote 1: Sam Tellig reviewed an earlier version of this speaker in January 1985 (Vol.7 No.8).—Ed.

Footnote 2: No, really, I don't use a hearing aid. That's a little joke. Excuse me, what did you say?

Spectrum Audio
company no longer in existence