Stand Loudspeaker Reviews

When Sefton visited my home to set up the new SRBs, he placed the speakers 7' 6" apart, facing directly forward, with no toe-in, 11' 6" from my listening chair and 3' 8" from the rear wall. The sound was spacious, detailed, immediate. Scott told me that the preferred vertical listening axis is anywhere from slightly below the tweeter axis, to the midpoint between the woofer's axis and tweeter's axis, taking into account the slight tilt of the speaker's front baffle; this matched the height of my listening position.

After Sefton left, I experimented, settling on a setup with listening position about 10'8" from the speakers, 3' 2" from the rear wall, and with very slight toe-in. I traded some soundstage size for center-image specificity and body. Bass response improved. The soundstage was still spacious.

During our phone interview, Cora told me that the room plays an especially important role with the SRBs. "In a typical room, I would say [it's] 60% room and 40% speakers," he said. "So, you really do need to play with the placement based on your room." My room, which has moderately large volume, glass windows spanning much of the front wall (shades normally down for listening), and concrete ceilings, can be quite lively, so I expected the speakers to sound different here than they did at the Florida show. They did.

Cora said in our interview that one of his design goals was to create a speaker that could be driven by almost any amplifier: "They are very easy to drive, with tubes or transistors. They don't care. They're relatively benign."

Then he said something that seemed almost paradoxical. "On the downside of that, though, is that it's really going to show off whatever your equipment can do," Cora continued. "It lets everything before it just pass right through." Translation: You can drive 'em with anything, but you'll hear it if it doesn't work. The Acoras, he added, are too revealing to work well with, for instance, some early class-D amplifiers. He has had the most success pairing his speakers with tube amps. At the Florida show, they were demoed with VAC's Sigma 170i iQ integrated amplifier. I got one of those in for my Acora audition; review forthcoming.

The majority of my SRB listening time was spent with two integrated amplifiers, one class-D (but not early), the other tubed: the MBL N51 and the above-mentioned VAC Sigma 170i iQ. The N51 has served as my long-term reference, providing power to a variety of speakers. In most contexts it's full-bodied and rich-sounding, with some warmth. Its sound is familiar to me.

Toward the end of my listening, for reasons that will soon become apparent, I also swapped in a "wild card" test: the solid-state Soulution 330 integrated, which operates in class-A.

Listening
I mainly listened to vinyl with the SRBs, but also a few CDs. The SRB did indeed prove revealing of fine details of particular recordings. This set my curiosity on repeat: I kept saying to myself, "I wonder what this one will sound like with these speakers." The Acoras kept me up late many nights, listening.

I have never experienced a loudspeaker for which amplification made a bigger difference, not with amps that were sufficiently powerful. I began with some familiar LPs that were audiophile-quality or at least well-recorded, and with the VAC Sigma 170i integrated amplifier. A 45rpm reissue of Muddy Waters's Folk Singer (Analogue Productions APB 1483-45) exposed the 1963 recording's raw character: studio echo, guitar-amp clipping, the up-close presence of Waters, Willie Dixon, and Buddy Guy in the small booth. Spooky.

It had been a while since I'd listened to Madeleine Peyroux's Careless Love (LP, Mobile Fidelity MFSL 1-284). On cuts like "Don't Wait Too Long," I picked up more detail in diction and expression in her often-understated vocal delivery than I'm used to hearing. Rhythms felt steady, and David Piltch's double-bass notes seemed to linger.

Cymbal and snare taps and brushstrokes stood out, crisp and smooth. It brought contentment like basking in warm sunlight, and it lifted my pandemic-dampened spirits.

Switching in the MBL N51, the pace on these Peyroux tracks felt swifter, the double bass deeper. The stage shifted farther back. Image scale seemed more realistic, and the specificity of the musicians' positions seemed better defined. The soundstage lost a little bit of depth. The crisp, clean, detailed presentation was a bit less rich than before—unusual for the N51—but it was not less musical.

Some of the material on Fellover My Own (LP, SofaBurn SBR1-035), by chamber-pop group A Delicate Motor, has seemed to me more compelling intellectually than emotionally. But with the SRBs and the VAC, Adam Petersen's vocals sounded nuanced and dynamic, even haunting. The first couple of cuts feature a kalimba, or thumb piano, which sounded crystal-clear and realistic in timbre (footnote 3). So did other delicate percussive sounds: an egg shaker; a bicycle tire spun with gentle clicks.

With the same music and the MBL, bass and drums became more prominent. More microdynamic details emerged, with more clarity: clicks, clangs, whirs of found objects, the reedlike vibrato of subtle vocal incantations.

The VAC tube amp gave up a little bit at the extremes but gained bloom, body, and dimensionality. The N51 brought those extremes plus detail, precision, and speed. With the class-D amp, the funky bassline on "Turn the Light" from Lux Prima (LP, BMG 538446291) was punchy and taut, a counterpoint to Karen O's sassy, warbling vocals. The percussive energy of the persistent driving beats (plus tambourine) on "Woman" hit hard. The N51/SRB combo's speed, snap, and detail served the Beastie Boys' Paul's Boutique well (LP, Capitol 509995 93300 18): the endless samples, stops and starts; the tight beats; the silly rapper rhyming antics; the funky rhythms and music. Bass lines were tight, samples vivid and real: the gurgle of a carbonated beverage pour, the bouncing of a ping-pong ball.

But: Strangely enough, when paired with the SRBs, the MBL lost its usual fullness, body, and substance—something I had never experienced before. Some recordings exposed the differences more than others. With the MBL amp, I found myself needing to turn up the volume more than usual, as if something were missing that I wanted to hear. On Surfer Rosa by The Pixies (LP, 4AD CAD 803/ROUGH US 38), in the intro to "Gigantic," Kim Deal's voice seemed higher-pitched than it actually is. The "grungy" guitar outro that deliberately repeats almost ad nauseum sounded "off" in tonal balance, slightly blanched and less heavy than usual. This occurred with the CD and the LP.

On "Gloria's Step," from the classic Sunday at the Village Vanguard by the Bill Evans Trio (Mobile Fidelity Ultradisc One-Step 45rpm LPs UD1S 2-002), Evans's piano verged on bright, and LaFaro's bass seemed recessed when he wasn't soloing. The baritone and tenor saxophone on cuts such as "On Fire" from Tony Allen's The Source (LP, Blue Note 3768336) seemed to shift into the background, while cymbal taps sounded more forward.

These were isolated events, or at least extreme cases, distilled from much pleasurable listening. Some records—Dire Straits' Brothers in Arms is a good example—sounded just as they should. And yet I must conclude that the N51—usually a gorgeous-sounding, full-bodied, warm-sounding amp—simply was not an optimal match for the SRB.

When, toward the end of my listening time, I tried the class-A, solid-state Soulution 330 integrated, I did not hear these anomalies.

Tubes, solid-state, or class-D, percussion and vocals is where the Acoras stood out, sounding distinctive on such material. Sonic energy seemed freed up. The combination of detail, attack speed, and energy made listening intense and exciting.

Take the relentless, polyrhythmic, layered percussion on "The Great Curve" from Talking Heads' Remain in Light (LP, Sire SRK 6095), with guest Adrian Belew's searing guitar shredding through a Roland synth. The system with the SRBs and VAC unraveled complex rhythmic and instrumental threads into distinct elements, like untangling necklaces in a jewelry box. Explosive energy and attacks thrilled and occasionally startled in this immersive presentation. Goosebumps.

It was exciting, but just like any heightened experience—a roller coaster, a live concert close to the stage—you don't want it to go on forever. On rare occasions—and I do mean rare—what I was enjoying so much almost became too much. Occasionally, detail and articulation could seem exaggerated. The SRBs are probably not the best choice for background music. (Not that that would be an audiophile's goal.)

The upgraded granite stands did make a sonic difference, more than I expected. With the heavier stands, the SRBs sounded bigger. Resolution increased, including bass definition.

The Sigma 170i's taps are labeled with ranges of ohms: 2–4, 4–8, 8–16. With the nominally 8 ohm SRBs, I mainly used the 4–8 ohm tap. The different taps did affect the sound, significantly but not radically. Changing from the 4–8 tap to 8–16 seemed to add weight while giving up a bit of air and sparkle, and maybe some immediacy. When I moved from 4–8 to 2–4, the presentation shifted back and narrowed a bit.

With the 8–16 ohm tap, on Bryce Dessner's Concerto for Two Pianos, composed for the Labèque sisters (El Chan LP, Deutsche Grammophon 4818097), the pianos' placement downstage from the orchestra was apparent. The soundstaging expanded beyond the speakers. The concerto sounded lush and lovely, with natural timbre, effortless, smooth. About a quarter of the way into the third movement, I heard a brisk intake of breath that I hadn't heard before. Immersive listening. Piano is tricky to reproduce convincingly, but no problem here.

Conclusion
These aren't ordinary small two-way monitors. They sound bigger than they are. They are capable of producing an expansive soundstage. They are highly detailed and fast, with a feeling of microdynamic precision and quick-footed effortlessness. They can start and stop on a dime.

Partnering amplifiers should be chosen with care. The VAC tubes worked especially well.

Bass extended deeper than expected and had good clarity and definition—and yet, in my room, the SRB's tonal balance ran mostly neutral to slightly cool, which makes me think my room was perhaps a little too large for them and/ or could have benefited from more absorption in this setup.

People who like warm, comfortable sound may find the SRB unforgiving on some material. I found them enjoyable and engaging across the wide range of music I played. These Acoras are best for active listeners who really want to hear what's happening in the music.

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Footnote 3: I'm no thumb-piano expert but I do own a couple, including one built into a resonator, that I schlepped back from Mozambique some years ago. So I'm generally familiar with their sound.