One glance at MarkAudio-SOTA’s Viotti One, and you might think something’s missing: a tweeter. But if you’ve attended a high-end audio show recently, you might not be surprised. Many of the latest exotic high-end speakers replace the usual woofer/tweeter or midrange/tweeter array with a single driver designed to cover most or all of the audio spectrum. The goal is to eliminate any sonic colorations created by the crossover circuit, or at least to push them down to lower frequencies where they aren’t as readily audible.
The $2,995/pair Viotti One does things differently. It’s a two-way speaker with a crossover at 2.4 kHz, in the same range as most conventional woofer/tweeter two-way speakers. The idea with the Viotti One is that, by using similar driver designs for the woofer and the midrange/tweeter (which is practically impossible with a conventional one-inch tweeter), the sonic character of the speaker will remain consistent throughout the audio range. A side benefit is that the Viotti One’s 5cm midrange/tweeter should play louder with lower distortion than a one-inch tweeter.
The downside of using a larger driver for treble frequencies is that a driver’s dispersion is mostly a function of its size. A driver’s dispersion starts to narrow at the wavelength that corresponds to the driver’s size. Narrowing of dispersion tends to make a speaker sound less open and airy, and sometimes it may cause “cupped hands” coloration, which makes singers sound as if they have their hands cupped around their mouths. In the case of the Viotti One’s midrange/tweeter, with an effective radiating diameter of 2.25 inches, the dispersion should be expected to start narrowing at about 6 kHz, compared with 13.5 kHz for a one-inch tweeter. I’ve heard lots of full-range speakers with a single driver, and I know how those tend to sound, but I’ve heard only a couple of speakers that use a single dynamic driver for the midrange and treble, so I was especially curious to hear what the Viotti Ones would sound like.
While $2,995/pair may seem pricey for a small two-way speaker, the Viotti One seems a notch or two above many competing models in many ways. A nice set of stands, designed for the Viotti Ones, is included--and is necessary, because at 21 inches high the Viotti One exists in the netherworld between a bookshelf speaker and a tower speaker, and typical stands won’t hold it at the appropriate height for best performance. The symmetrical second-order crossover is built into its own chamber to isolate it from the drivers’ back waves. The exterior is coated in a real seven-layer, hand-polished lacquer finish, in your choice of black, white, or light or dark oak. High-quality four-way speaker cable binding posts are provided; biwiring is not accommodated. The magnetically attached grille looks great and is engineered so that the sound doesn’t bounce back and forth between the grille and baffle, and thus it doesn’t cause the harsh comb filtering effects that many grilles produce.
I did most of my listening to the Viotti Ones using a Classé CP-800 preamp/DAC, a Classé CA-2300 stereo amp, a Music Hall Ikura turntable plus an Audio by Van Alstine AVA ABX switcher for level-matched comparisons. I used Wireworld Eclipse 7 interconnect and speaker cables.
After the manufacturer-mandated 100-hour break-in period, I did some quick listening to the Viotti Ones to get them positioned for the best sound. In my room, that meant the backs of the speakers were 25 inches from the walls behind them, and the centers of the speakers were nine feet apart, with each speaker’s front baffle 10 feet from my chair. Both speakers were pointed straight at my listening position. I tried listening with the grilles off, but the treble was just slightly too bright for my taste; so, I left the grilles on for the rest of my listening.
The only speaker I’ve reviewed that’s anything like the Viotti One is Meridian’s DSP3200, which has a similar driver arrangement but uses internal amplifiers with heapin’ helpings of digital signal processing. So I wasn’t sure what to expect from the Viotti Ones.
Fortunately, from the first notes of Meshell Ndegeocello’s recording of “Please Don’t Let Me Be Misunderstood,” I could tell the Viotti One wasn’t some idiosyncratic boutique speaker. In fact, it didn’t exhibit any obvious distinctive sound character of its own--it just sounded good. This recording has a nice sense of space, and through the Viotti Ones the heavy reverb was readily apparent and created a clear simulation of a large hall. Ndegeocello’s voice also stood out nicely in the mix without sounding exaggerated. Overall, the sound seemed unusually vivid and lively, but the speakers accomplished this with no overt coloration or unnatural sonic characteristics.
Pianist Bill Evans’ recording of “Polkadots and Moonbeams” sounded similarly appealing, with the Viotti Ones producing a convincing portrayal of how Evans’ trio might have sounded in a typical small jazz club. The piano sounded intimate and not particularly large or reverberant, but Paul Motian’s cymbals sparkled and exhibited a nice sense of space. All of bassist Chuck Israels’ notes, even the deepest ones, rang out full and clean with no boominess or bloat. “This speaker’s a lot of fun to listen to,” I noted, largely because it didn’t seem to favor any particular kind of music and didn’t have any characteristics of its own that caught my attention.
Even highly artificial recordings such as Major Lazer’s “Cold Water” didn’t change my impression of the sound. Justin Bieber’s vocal was precisely centered, while the various electronic squiggles circled around him, wisely keeping their distance. The 11cm woofers couldn’t, of course, shake my floor with the tune’s deep bass tones, but they never sounded strained, and the sound was always full and satisfying.
R.E.M.’s crude-sounding Chronic Town EP presents a tough challenge for speakers because it was recorded in a low-rent studio by guys who’d only been playing their instruments for a couple of years. Still, “1,000,000” sounded pretty darned good through the Viotti Ones. As with the Meshell Ndegeocello recording, the speakers somehow brought out the vocals from the mix without noticeably coloring their sound or emphasizing them in artificial ways. This tune sometimes sounds thin; I suspect that’s because of the recording, the mix, or the quickie nature of the production, all of which exacerbate any bass reproduction problems a speaker might have. Through the Viotti Ones, “1,000,000” sounded nicely full without appearing to boost or shape the bass in any way. Once more, the Viotti Ones just sounded good.
The Viotti Ones don’t seem to have been designed with home theater in mind, but I decided to play a few movies through them anyway, using a Dayton Audio SUB-1000L slim subwoofer crossed over to the Viotti Ones at 80 Hz by the Classé CP-800’s internal crossover. With Captain America: Civil War, the recent movie that pits Captain America against Iron Man, I enjoyed the clarity that the Viotti Ones brought to the dialogue and special effects. I didn’t blast the volume to extremes, but the Viotti Ones handled the moderate-to-slightly loud level well, with no distortion, harshness, or thinning out of the sound, always keeping the dialogue out front and center in the mix, right where it belongs.
Click over to Page Two for Measurements, The Downside, Comparison & Competition, and Conclusion…
Here are the measurements for the Viotti One speaker (click on each chart to view it in a larger window).
min. 5.0 ohms/6.1 kHz/-8.0, nominal 9 ohms
Sensitivity (2.83 volts/1 meter, anechoic)
The first chart shows the frequency response of the Viotti One. The second chart shows the impedance. The computer that runs my LMS analyzer broke down as I was putting these measurements together, so I am temporarily unable to present charts with average responses. In the meantime, I’ve presented a chart showing the response at 0° on-axis and 10, 20, 30, 45° and 60° off-axis. Ideally, the 0° curve should be more or less flat, and the others should look the same but should tilt down increasingly as the frequency increases.
This is a pretty flat response for a speaker of this type. There’s a dip in the midrange from about 1.3 to 3.2 kHz, and the treble has the spiky on-axis response typical of midrange/tweeters. The response is smoother off-axis, which is why the averaged responses are smoother than the on-axis response. Unusually, the response is considerably flatter with the grille on; removing the grille increases that midrange dip by -2 to -3 dB and increases the magnitude of the treble spike above 10 kHz. This is presumably because the effects of the waveguides built into the grille are incorporated into the speaker’s voicing. So leave the grilles on!
Sensitivity of the Viotti One is slightly low at 85.4 dB (measured at one meter with a 2.83-volt signal, averaged from 300 Hz to 3 kHz), which means the Viotti One can hit 100 dB with about 30 watts. Impedance runs fairly high, so any amp that puts out at least 50 or so watts per channel should be able to get this speaker up to a satisfying volume.
Here’s how I did the measurements. I measured frequency response using an Audiomatica Clio FW 10 audio analyzer with the MIC-01 measurement microphone, and the speaker driven with an Outlaw Model 2200 amplifier. I used quasi-anechoic technique to remove the acoustical effects of surrounding objects. The speaker was placed atop a two-meter stand. The mic was placed at a distance of one meter on the center axis of the midrange/tweeter, and a pile of denim insulation was placed on the ground between the speaker and the mic to help absorb ground reflections and improve accuracy of the measurement at low frequencies. Bass response was measured by close-miking the woofer and port, then scaling the port response appropriately and adding it to the woofer response. I spliced this result to the quasi-anechoic results at 220 Hz. Results were smoothed to 1/12th octave. Because the grille is integral to the design of the speaker, I made measurements with the grille on except as noted. Post-processing was done using TrueRTA software.
Physics is physics, and a 5cm driver just isn’t going to disperse high frequencies as broadly as a conventional one-inch tweeter. This didn’t cause the “cupped hands” coloration I feared, but it did reduce the openness of some vocal recordings, such as Cecile McLoren Salvant’s “What’s the Matter Now?” That appealing vividness I heard before was still audible, but the sound did seem more directional--more like it was coming from speakers rather than actual performers--than it did with my reference Revel F206 speakers. Granted, the F206s have perhaps the most open sound of any dynamic speakers I’ve tested. Still, I have to say that the Viotti Ones sound no less open and spacious than many speakers with a conventional one-inch dome tweeter.
Likewise, physics limits how deep and loud an 11cm woofer can play. The Viotti One’s woofer plays deep enough for almost any jazz recording and most pop recordings; but, when I played the Major Lazer tune, the bass didn’t hit with any real authority. Same for the Cecile McLoren Salvant tune. The speaker’s fairly large size for a non-tower model gives it a reasonable amount of bottom-end oomph, similar to what I’ve heard from some small tower speakers; however, if you want deep, powerful bass, you’ll have to add a subwoofer.
Comparison and Competition
One obvious competitor to the Viotti One is the $2,000/pair Revel Performa M106, which has a 6.5-inch woofer and a one-inch tweeter. The M106 sounds quite similar to the F206, so my notes above should give you an idea of how it compares with the Viotti One, and it may play slightly deeper because of its larger woofer. However, the M106 is a rather utilitarian speaker; it’s well made but nowhere near as pretty as the Viotti One.
Another potential competitor is the $2,199/pair Monitor Audio Gold GX50, which has a ribbon tweeter with a 5.25-inch woofer. To the best of my memory, I think the GX50 will sound more spacious than the Viotti One, but it doesn’t have that nice midrange vividness that the Viotti One exhibits.
HomeTheaterReview.com has recently tested two bookshelf models that seem competitive with the Viotti One. I haven’t heard them at length, but you can check out the reviews to get an idea of how they sound. These include the $3,699/pair Clearwave Loudspeaker Design Resolution BE, reviewed by Terry London and the $3,000/pair Thiel TM3, reviewed by Myron Ho.
I enjoyed listening to the Viotti One no matter what material I was playing. I worried that its somewhat exotic design might make it fussy about placement or might make it favor certain types of music or recordings, but in actual use the Viotti One was much more friendly and easy to get along with than most exotic high-end speakers. In fact, what’s most remarkable to me about the Viotti One is that, as unusual as its design is, it’s more of a subtly different and delightful twist on the conventional two-way speaker, rather than a radical departure.