Dunlavy Audio Labs SC-IV/A loudspeaker:
Page 3 The effects of such a low level of speaker coloration were several. First of all, there was a timbral accuracy to a wide variety of instrumental sounds and voices that was at times quite startling. Ida Levin's violin on Duet (Stereophile STPH012-2) had the combination of sweetness and astringency I remember from her concert at HI-FI '98. Singers whose voices I'm familiar with from live performances sounded more like themselves and less like reproductions. There was also a significant improvement in resolution.

The SC-IV is certainly no slouch in this department, but with the SC-IV/A I was able to hear complexities in the musical texture that had previously been obscured. This enhanced resolution was real, not an artifact of a frequency-response boost in the upper midrange/low treble. If anything, the SC-IV/A was smoother, even a touch laid-back through this range, with sibilants that could occasionally sound a bit spitty through the SC-IV now sounding more smooth—as if the recording had been rerecorded with better microphones.

The SC-IV/A's sound had tremendous coherence: despite being a complex multiple-driver system, it speaks with one voice. There is exceptional top-to-bottom integration, with no audible cues as to where in the range the different drivers take over. One visiting audiophile friend who was unfamiliar with the speakers said that if I hadn't taken off the grille to show him the drivers, he would have thought he was listening to a speaker with a single driver.

The SC-IVs have always been imaging champs; I can't say that this aspect of performance was improved with the SC-IV/As, but it was certainly maintained. For the centrally located listener, both speaker models had a specificity of imaging unbettered by any other speaker I know of. Where the SC-IV/As did score over the SC-IVs was in their tonal balance and imaging for the off-center listener.

There's a well-known tradeoff in speaker design between sound quality for one listener vs multiple listeners. A talented designer can transcend the limitations of any design approach; but in going with a first-order crossover, the designer effectively chooses to maximize performance for the centrally positioned listener, giving up some sound quality for the off-center listener. Designs based on higher-order crossovers sound well balanced over a wider area, but their specificity of imaging for the centrally located listener tends to be not quite as precise as the best first-order designs. The SC-IV/As came a little closer to offering the best of both worlds. Central imaging had that "holographic" quality, but the sound for the off-center listener didn't seem to fall off as much as with the SC-IVs.

Having been told of the midbass peaks in the frequency response of the nonequalized ScanSpeak woofer, I listened carefully for audible indications of problems in this area, but heard nothing that I couldn't attribute to room modes. String bass sounded tight and tuneful, with just the right combination of fundamental and harmonics; timpani sounded crisp, with no excessive overhang. Whatever the problem with the raw woofer, Dunlavy had obviously found the solution.

And how was the Dunlavy's deep bass? Stupendous! Measured anechoically, the SC-IV/A's rated -3dB point is specified as 20Hz, compared to the SC-IV's 33Hz. Keeping in mind that going from 40Hz to 20Hz represents an entire octave, this is a big difference. Even 33Hz is more than respectable, and, with room lift, results in extension to the low 20s. Anechoic -3dB at 20Hz translates to the kind of weight and authority that is usually the domain of serious subwoofers, which are usually difficult or impossible to integrate with the main speakers in a time-coherent manner. With a pair of Bryston 7Bs in charge, my usual low-bass test pieces, like track 7 of Planet Drum (Rykodisc RC-10206), came through with a room-shaking power that was almost scary. Performance with the Sonic Frontiers Power 2, a tube design, was also very impressive, if not quite as stygian.

The quality of the bass was exceptional: low apparent distortion, well integrated into the rest of the range, with not a trace of boominess. The bass was "quick," contributing to the dynamic feel of the rest of the speaker's range.

Conclusion
Remember the frog whose jumps always take him halfway toward his goal? Audiophiles and audio manufacturers are much like that frog, approaching but never quite reaching the goal of perfect fidelity. Or, as Paul Simon put it, "The nearer your destination, the more it keeps slidin' away."

With the SC-IV/A, Dunlavy Audio has managed the feat of jumping more than halfway toward the goal. Very simply, this refinement of the SC-IV has reached the point where—with the best source materials and associated equipment—it sounds less like a speaker and more like the music that's being reproduced.