Description: 3.5-way planar magnetic/isodynamic loudspeaker with a proprietary ribbon tweeter. Frequency range: 22Hz–24kHz. Crossover frequencies: 600Hz and 7kHz. Sensitivity: 89dB/W/1m. Impedance: 4 ohms. Power handling: up to 300W (recommended power <60W). Single binding posts (no biamping).
Dimensions: 71" H (1803.4mm) × 25.6" (650.2mm) W × 13.3" (337.8mm) D, 189lb (85.7kg) each for the MkI Evo; 73.2" (1859.3mm) H × 28" (711.2mm) W × 15" (381mm) D. Weight: 194lb (88kg).
Finish: Black or white; custom colors available for an extra $1200.
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Sidebar 1: Specifications
Sidebar 2: Associated Equipment
Analog sources: Technics SL-1200MK5 'table with KAB 3-speed mod, fluid damping, and tonearm wiring; Hana SL MK II, Shure V15 Type III, LP Gear The Vessel A3SM, Ortofon 2M Blue, Denon DL-110 cartridges. Philips AF-887 turntable with Shure M97xe.
Preamplifier: Benchmark LA4.
Power amplifier: Benchmark AHB2.
Integrated amplifier: McIntosh MA6500.
Loudspeakers: Bowers & Wilkins 808, Amphion One18.
Accessories: Butcherblock Acoustics equipment rack, SME turntable cable, various cables and connectors made by Belden, Canare, Mogami,…
EISA, or the Expert Imaging and Sound Association, is an organization representing 53 of the most respected special interest publications and websites from 26 countries that cover Hi-Fi, Home Theater, Photography, Mobile Devices, and In-Car Electronics. Every year EISA's Expert Group members, including editors from this publication, test a very wide range of new products from their field of expertise before comparing results and voting to decide on the cream of every product category.
To win an EISA award all products undergo a comprehensive multi-step judging process, and many still…
Shortly after the July 2013 issue of Stereophile hit the newsstands, I received an e-mail from audio restoration expert Doug Pomeroy, who specializes in the digital preservation of disc pressing metal parts, acetates, and 78s. (For an example of his excellent work, see www.nytimes.com/2010/08/17/arts/music/17jazz.html?pagewanted=all&_r=0.)
I first spoke with Pomeroy in 2001, for a story about digital audio published in a Village Voice music supplement. His and my opinions about digital sound couldn't be more divergent. Pomeroy's experience dwarfs mine, but I haven't budged from my…
In high-end audio, Italian designs play by different rules. They tend to favor beauty over austerity, boldness over caution, and emotion over restraint. Rather than just hearing the music, you're meant to be swept away by it. That spirit animates gear from Unison Research, a tube-focused company located just north of Venice. Founded in 1987 by Giovanni Maria Sacchetti, the brand was taken over in 2000 by audio entrepreneur Giovanni Nasta, who brought it under the umbrella of A.R.I.A. (footnote 1), the company that manufactures Opera loudspeakers.
Today, five years after Nasta's untimely…
Brian Wilson in 2015. (Photo by Brian Bowen Smith.) Though he long ago guessed he just wasn't made for these times, Brian Wilson left a musical legacy that was built to last, long after summer's gone.
Outside of Vincent Van Gogh, Brian Wilson had the most infamous—and ultimately the most valuable—left ear in the world. Wilson—the chief architect of countless Beach Boys pop classics, who passed away at age 82 on June 11, 2025—lost the hearing in his right ear at an early age (footnote 1). One could reasonably argue that he only ever heard all the sonic masterpieces he constructed, for that…
Sidebar 3: Measurements
I measured one of the X Diamond Mk II loudspeakers, serial number 65793A, in RvB's listening room, driving it with his Krell FPB-200c amplifier. I used DRA Labs' MLSSA system with a calibrated DPA 4006 microphone to examine the speaker's behavior in the farfield and an Earthworks QTC-40 mike for the nearfield responses. It wasn't possible to raise the 190lb loudspeaker off the floor for the measurements, so the first reflection from the ground occurs earlier than is usually the case with my testing. I therefore measured the response and dispersion with the…
Sidebar 3: Measurements
I performed a complete set of measurements on one of the Unison Research Reference amplifiers (serial number 350072R) with my Audio Precision SYS2722. The amplifier preserved absolute polarity with both the balanced and unbalanced inputs and one of the two sets (8 ohm and 4 ohm) of output transformer binding posts. As mentioned in the amplifier's user manual, the two sets of binding posts are connected in parallel. A rotary knob on the front panel simply acted as an on-off switch. The gain was identical, at a low 16.2dB, with both types of inputs and, unusually,…
Sidebar 2: Associated Equipment
Digital sources: Aurender A20 streamer and DAC, Grimm Audio MU1, Evernote DMP-A10, Sony S9000ES SACD player, 16" MacBook Pro M1 Max running Roon 2.0, Lenovo ThinkCentre running Roon ROCK.
Preamplifier: Unison Research Reference Pre, Benchmark HPA4 line stage.
Integrated amplifier: Pathos InPoL Legacy.
Loudspeakers: Focal Utopia Scala Evo, Estelon X Diamond Mk II.
Cables: Speaker: AudioQuest Thunderbird Zero and Bass. Interconnect: AudioQuest Black Beauty RCA, Clarus Crimson XLR. Digital: WEL Signature AES3; AudioQuest Coffee S/PDIF;…
Sidebar 1: Specifications
Description: Mono tube power amplifier operating in class-A with a double parallel single-ended output stage. Tube complement: Four 845 power triodes, one ECC82, one ECC83. Inputs: one RCA, one XLR. Output power: 80W into 8 ohms (19dBW). Frequency range: 20Hz–30kHz. Feedback: 14dB. Input impedance: 47k ohms RCA, 10k ohms XLR. Output impedance: Two taps, 4 ohms and 8 ohms. Power consumption: ~400VA.
Dimensions: 19.3" (490mm) W × 30.5" (775mm) D × 11.2" (285mm) H. Weight: 155lb (70.3kg).
Price: $49,998/pair. Number of US dealers: 31.
Serial numbers of…