Alta Audio Alyssa

At first look, our November 2020 review of the standmount loudspeaker ($5000/pair) from Alta Audio1 appeared to be a thorough vindication of the Stereophile method of reviewing, combining measurements with a subjective listening journal. John Atkinson’s measurements were generally fine, but he uncovered “strong discontinuities in the impedance traces at 174Hz and 291Hz [that] imply the presence of resonances.” They could only be internal airspace resonances, since he found the Alyssa’s cabinet to be admirably inert.

By Jim Austin

Nearfield measurements of the port and woofer showed response peaks close to those same frequencies. The sonic and musical effects of such resonances would at worst be modest, but they could be audible; in fact, John predicted that they would be. “I would expect this behavior to color the sound of male vocals,” John concluded.

Independently—Stereophile reviewers don’t see measurements until after their review is submitted—Herb Reichert reported “a vexing lack of focus in the lower midrange and upper bass.” It was especially noticeable in male vocals, including two tracks he auditioned from Ry Cooder’s album Jazz.

Herb wondered, “Was it the speakers I was hearing or their interactions with the room and my amplifiers?” Because of his room’s modest dimensions, Herb avoids speakers he thinks might overload it. He reviews almost exclusively standmounts, smaller floorstanders, plus the odd smaller Magnepan. The Alyssas are standmounts, but they go deeper than is usual for standmounts of their size and weight. “In a larger space, with lower levels of reflected bass energies, the Alyssas would, perhaps, present themselves with a more balanced tone and sharper lower-midrange focus. Perhaps another Stereophile reviewer can audition these speakers in a larger room.” I decided to try to answer Herb’s conjecture.

My room isn’t perfect,2 but it’s big, and I’ve rarely had any serious problems with room interactions—just the usual bass modes, and here they’re reasonably tame and well-spaced.

Based on conversations we’ve had, I would describe Mike Levy, Alta Audio’s CEO and chief speaker guy, as an intuitive designer who prioritizes what he hears over design orthodoxy. An example: He doesn’t believe in stuffing his speakers with lots of sound-absorbing foam, which can lower the Q and hence the level of internal resonances but only, he believes, at the cost of musical realism.

The conventional wisdom about low bass, here at Stereophile at least, is that it’s nice but not essential. Levy disagrees. To him, low bass is a necessary foundation for music. So, when he set out to design a small standmount loudspeaker, producing low bass was a necessary design goal. His solution was to combine two ideas that usually are employed separately: bass reflex and transmission line, putting a longish, skinnyish port tube at the end of a folded pathway. Conventionally, transmission lines are stuffed to soak up resonances—but as I already wrote, Levy doesn’t like stuffing. The result is what you might expect: John’s measurements found both an unusually low port-tuning frequency for a speaker of this volume—32Hz—and the aforementioned internal resonances. That’s a fine tradeoff if the resonances are inaudible or sonically unimportant. But in that case, what was Herb, who has an exceptional ear for reproduced music, hearing? My job was to evaluate the audibility of those upper-bass/lower-midrange airspace resonances and figure out what was causing the lack of focus Herb heard.3