Apogee Duetta II loudspeaker Anthony H. Cordesman

Anthony H. Cordesman reviewed the Duetta in September 1986 (Vol.9 No.7):

I normally like to listen for several weeks before commenting on a new product, particularly one that I feel breaks as much new ground as the Apogee Duetta II. Anyone who remembers the one time High Fidelity ever heard an audio product that sounded truly different, and praised it as such, will probably remember that the product the magazine praised as redefining the state of the art was the Bose 901. At the same time, the Duetta II breaks so much new ground, and is so obviously a superb speaker system, that it simply would not be fair to you readers to put off reporting on this speaker until the next issue.

In fact, my wife's reaction to the Duetta II may be worth a thousand of my words. I had just unpacked the Apogee Duetta Series II, and set it up in the manufacturer's recommended position. I hadn't gotten around to really listening yet, and was still checking the speaker position and wiring as the Duetta IIs played, but my wife was sitting in the listening area. I thought she could tell me whether the channels were balanced, and asked her what the speakers sounded like.

The response I got was a great deal more dramatic than a comment on whether the channels were balanced. An exact quote: "They are the first speakers I've ever heard that remove the veil from the music that always tells you that you are listening to a hi-fi system." Well, my wife has heard virtually every high-end speaker that I've heard, including the Apogee Scintillas, the Quad ESL-63s, and the Infinity RS-1Bs that I have used as reference speakers. She is not given to ready praise. In fact, she is apt to sulk for several days after every major disruption of her living room, and be extremely critical of any speaker simply because it is new.

As a result, I immediately stopped tweaking and started listening. It was worth it! I suspect it may be weeks before I find the right room placement, amplifier, and speaker cable to get the best out of this speaker. I am already sure, however, that I have never heard more detail and information in a more musically natural form. It may be years before Apogee fully explores the limits of ribbon speaker technology, but the Duetta II is a superb product, and redefines the state of the art in many important respects.

Design Evolution in the Duetta II
Let's take a few minutes before I describe the sound, however, and go over the design evolution of the Duetta II. As you have already read in these pages, the original Duetta built on the technology of the large Apogee and Scintilla, and provided a more affordable all-ribbon speaker, one that many good amplifiers could drive.

The Caliper showed, however, that Apogee could do much more to produce a musically realistic sound, and at a much lower price. Further, Apogee made progress in a research program on canted ribbon transducers which could act as both midrange and tweeter. This progress showed that such a ribbon could provide excellent horizontal dispersion and realistic vertical imaging in a comparatively short length. Apogee also developed proprietary new approaches to ribbon suspension and mechanical acoustic shaping, which improved the smoothness of the sound of the combined midrange and tweeter (MRT) ribbon. As a result, it found that the use of a single ribbon eliminated potential time-alignment problems inherent in the use of separate midrange and tweeter ribbons.

The Duetta Series II speaker draws on other improved ribbon speaker design techniques which Apogee developed in designing and manufacturing the Caliper. For example, Apogee uses multi-sloping crossover shaping with a 6dB/octave slope at the crossover frequency, and uses a rear panel switch to add a gentle 2dB rolloff at the high end of the MRT to adjust tonal balance to different rooms and source material.

The Duetta Series II also incorporates a provision for an active crossover in the biamped mode. Apogee says that the use of this crossover improves resolution and tonal balance adjustment, gives you 3dB more headroom, and provides superior woofer and midrange shaping. I have not yet had a chance to use this unit, but will report on it when I give you my final thoughts on the sound of the Duetta IIs in the next issue.

Redefining Transparency
I must again stress that proper listening to speakers takes weeks—not days—of experimentation. Accordingly, you should use my comments as a comparative reference for your own listening, and not as revealed truth. (Does any one ever pay that much attention to an audio critic?) Nevertheless, my reactions after a week of intensive listening are:

Deep Bass: Not present in the same strength and power as the larger Apogee and Infinity speakers, but very much there nonetheless. The best cone subwoofer systems are still superior in this area, but only with exact placement and superb active crossover designs and drive amplifiers. Coupled to the extraordinary flatness of the mid and upper bass, the feeling of deep bass power is far more satisfying than in any competing dipole, including the highest-priced electrostatics and Magnepans.