Audio Research DSi200 Integrated Amplifier (TAS 204)

Not Your Daddy’s Class D

When it comes to tube electronics few high-end companies speak as authoritatively and have been as honored as the Audio Research Corporation. On a far more personal note is the memory of a system I regularly enjoyed thirty years ago at a friend’s home–an ARC SP3a preamp and D150 power amp driving Magneplanar Tympani 1Ds, which had speed and transparency on a scale that gives me goosebumps to this day. ARC’s solid-state line, on the other hand, while highly respected has not been recipient of the kind of reverence reserved for its tube offerings. However, ARC’s latest, the new DSi200 integrated amp, makes a stronger case than ever. It’s a solid-state design with a secret.

From any point of view, the look of the DSi200 is pure Audio Research—from its classic squared line, to the heavy front panel and chunky grab handles. Large volume and input selectors flank a vacuum-fluorescent display whose brightness has six levels of adjustment. Beneath the display are four aluminum buttons for power on/off, mono/stereo, inverting phase, and muting output. These same functions, as well as a balance control and display adjustments, are also provided by a full-function remote control. The back panel sports three single-ended inputs and a pair of balanced inputs—their mirror-like, symmetrical layout exposing the dual-mono design of the amp’s circuit. The DSi200 is also available with a black front panel, handles, and knobs, but the chassis and wraparound cover are only be available in silver.

The aforementioned secret is the DSi200’s solid-state-hybrid design. It combines a hefty regulated analog linear power supply with a discrete MOSFET-based high-speed switching output stage of ARC’s own invention. While this implementation is not unique, ARC points out that, unlike virtually all other switching amplifiers, the DSi200 does not rely on any OEM modules or pre-manufactured components. The resulting amplifier outputs 200Wpc continuous into 8 ohms (300W into 4 ohms) with very high efficiency energy conversion—over 90%. Typical of this class of amp, the DSi200 runs very cool and because it draws only a scintilla of power at idle it garnered an “Energy Star” rating

I had the DSi200 powered up for only a few minutes when it became plain how authoritatively it reproduced music, particularly the lower mids and bass. Its ease and realism with pitch and timbre in the “nether regions” were superb. However, my broader impression was that the upper mids and treble range seemed out of character for an Audio Research component—they were a bit congested and tightly wound, and not playing ball with the mids. Since ARC is straightforward in stating that a significant amount of break-in time is required before the DSi200 settles in, I realized I would be remiss in not taking this caveat seriously. Long story short: I left the amp powered up cycling through the blips, ticks, and bumps of an Isotek burn-in disc for about a week straight without doing any serious listening. And the envelope please…

The difference was actually quite astonishing. Like a singer clearing her throat, the voice of the amp seemed to drop into a deeper more grounded place as if finally breathing from its diaphragm. It shed its papery thinness and smoothed out, like someone evening the wrinkles from fine bed linen. Violin, cello, dreadnought acoustic guitar, and even mandolin began resonating more fully and deeply. The DSi200 does not communicate an overtly sweet character in the sense of a darkened ripened treble, but neither does any astringency sour the top octaves. When I listen to violinist Arturo Delmoni play the “Allemande” from the Bach Partita No. 2 [Water Lily], I hear a sound that is neither shaded or spot-lit—just a marvelous sense of movement and action beyond the confines of the instrument itself. In this instance, there’s the thicker sound and increased body of the instrument coming into focus as Delmoni leans on the bow, digging into the strings for more volume and color. The ARC also reveals the air and open space looming behind the player, adding to the acoustic backbone of the performance. It individuates images and timbres with ease while also reproducing the interplay of textures within the soaring wind section during the playful allegro molto of Copland’s Third Symphony [Reference Recordings]. The stabs of brass, bass drum, and cascades of tympani during “Fanfare for the Common Man” were nothing less than electric. The DSi200’s grip on low-frequency pitches and timbres is steadfast; electric bass, kick drums, low percussion never lag or blur. Bass response is not overpowering but fast on its feet, allowing an acoustic bass to exhibit both volume and pace, not an easy act to balance. When it comes to midbass oomph, the DSi200 just seems to pull reserves from a seemingly bottomless well and yet never seems short of control even while driving demanding loads like the Magico V2 or TAD CR-1 loudspeakers.