Apogee Duetta II loudspeaker George Graves
Even though Apogee Acoustics' Duetta II, a full-range ribbon loudspeaker, has been reviewed a couple of times already in these pages (by Martin Colloms in Vol.10 No.1, by Tony Cordesman in Vol.9 No.7), their findings do not tell the whole story of the Duettas' sound in my opinion. In my efforts to elicit the very best from these loudspeakers, I've found them so cable-sensitive that one's opinion of how Duettas sound will depend to a very great extent upon what cables were used and whether or not the speakers were bi-wired.
The Apogee Duetta IIs are the most cable-sensitive speakers I have ever encountered. With Magneplanars, my regular speakers, cables make very little difference. The good ones may improve the character of the top end a smidgen, or slightly deepen or widen the soundstage, but these changes are, at most, subtle. With Duettas, however, in spite of the relatively easy, mostly resistive load it presents to the amplifier and speaker cables, the type of cable used will make or break this speaker system.
Apogee supplies shorting bars to strap the separate inputs for woofer and tweeter together, but recommends bi-wiring, whereby two sets of speaker cables are run back to the amplifier. They mean it! Conventional wiring results in a poorly defined sound with very little soundstage that, in view of their not inconsiderable cost, is very disappointing. Bi-wiring should be regarded as mandatory.
When I first received my Duettas, I had on hand only a pair each of Monster Cable Powerline II and FMS Gray cables. Since the Powerline was of a heavier gauge than the Gray, I naturally put it on the woofer, and connected the Gray to the midrange/tweeter ribbon. The result was terrible: The speakers had an unpleasantly honky, forward midrange. I was about to give up (being used to the unfussy Maggies, it never occurred to me that the cables could be at fault), so I called a friend who was an Apogee dealer. Upon hearing of my plight and listening to my explanation of my set-up, he made one suggestion: "Swap the cables." No, that couldn't be it. Cables never have that much effect on speakers. Out of desperation, I tried it. Whaddya know? Putting the FMS Gray on the bottom and moving the Powerline II to the top fixed the problem. Suddenly the speakers were fairly well-balanced in frequency response, except for a slight tubbiness in the midbass (about which more later) and a slight darkening of the top. The midrange glare was gone.
A couple weeks later, Monster supplied me with a set of their new top-of-the-line M1 speaker cables. I was able to replace the FMS and the Powerline II with these, and the quality of the sound changed again! This time the entire upper two octaves darkened considerably. At the same time, the soundstage grew wider and deeper, and imaging improved. The bass became tighter and better focused, with much-improved transient response. A mixed bag. I liked everything except the high-end darkening (the Powerline II did enough of that already). I finally found a good compromise by using the M1 on the woofer (which crosses over at about 500Hz) and going back to the Powerline II for the tweeter. But I still wasn't happy with the sound. If the Duettas had been lesser speakers, I would have just given up. But they kept promising more than I was able to elicit from them, and this drove me to keep trying.
I spoke with Jason Bloom, of Apogee, on the phone and told him of my cable saga. He agreed that the speakers were indeed picky, and suggested that a Swiss cable, the Symo, that he'd used on the more expensive Diva model might just do the trick on the Duettas. He then shipped me two pairs of sufficient length to use with my system. The Symo cable (retailing Stateside for about $15 a foot) is unprepossessing indeed. At first glance it looked a lot like Monster Cable's cheap Superflex. A closer examination, however, showed that this similarity is superficial. Both cables look like pinkish-clear 300 ohm TV twinlead that has contracted elephantiasis. But there the similarity ends; where the Monster consists of two loosely braided bundles of copper strands per conductor, the Symo has a single bundle of copper strands wound so tightly around a solid core that the windings appear almost perpendicular to the cable. The solid core also makes the Symo stiff.
Replacing the Monster M1/Powerline II combo with Symo changed the sound of the Duettas drastically: The top end was now open and fast, the highs sparkled, and triangles floated over the rest of the ensemble. The brasses had more bite, and the bass was tighter and better defined than ever before. All instruments had more air around them, and the imaging was the best so far. This change was overwhelming; it took me several more days of listening before I was ready to make any recommendations.
Recommendations: If you can afford it (and if you can get it—this stuff is hard to come by), I suggest you have your Apogee dealer sell you a full set of Symo. This will add about $600 (for four 10' lengths) to the overall cost, but will save you a lot in the long run. At today's speaker-cable prices, you can easily spend twice that just searching for the right cable. If you can't swing the Symo right away, then I would opt for the Powerline II by Monster. It's cheap (about $2.50 per foot) and degrades the performance of these speakers much less than do most other cables. The difference between Powerline II and the Symo is much less than between single wire and bi-wiring, so whichever cable you buy, buy four runs.