Sumo Theorem D/A processor Review context

Sidebar 1: Review context

I auditioned the four processors reviewed in this issue under identical conditions and at matched levels. Additionally, the reference playback system has remained nearly constant for the past year, providing a stable platform on which to audition and compare digital processors. The converters under review fed an Audio Research LS2 line-stage preamplifier, which in turn drove a Mark Levinson No.23.5 power amplifier via its unbalanced inputs. Loudspeakers were Hales System Two Signatures, occasionally augmented with a Muse Model 18 subwoofer.

A Theta Data Series II transport or Museatex CD-Deck provided the digital signal, and a variety of digital interconnects were auditioned with each processor. Other converters on hand for comparison included the Meridian 203, Theta DS Pre Generation III, Musik System Zero, and that low-cost standard, the Audio Alchemy Digital Decoding Engine. The excellent $1500 Musik System Zero provided a good benchmark for these much-lower-priced units under review, and the Audio Alchemy DDE brought another reference point at the lower end of the scale.

Interconnects included Expressive Technologies IC-2, AudioQuest Diamond, and Monster Cable Sigma. Loudspeaker cable was 8' runs of bi-wired AudioQuest Sterling/Midnight. All AC power to the processors was conditioned with a Tice Power Block and Titan, and all the processors were left on during the three-week audition (footnote 1).—Robert Harley


Footnote 1: Leaving your D/A converter on all the time ensures that it will always sound its best. If you turn it on just before listening, you'll never hear what it can really do. I find that it often takes several days or even a week before a processor reaches its maximum smoothness and liquidity. In addition, leaving the processor constantly powered reduces turn-on/off stress on internal components, increasing the product's life.
COMPANY INFO
Sumo Products Group
Agoura Hills, CA 91301
Company no longer in existence (2019)
ARTICLE CONTENTS

COMMENTS
Ortofan's picture

... "mediocre" - not even damning with faint praise this time.
$800 would have been much better spent on a Sony CDP-X339ES or, for something different, a Pioneer Elite PD-65, or even a JVC XL-Z1050TN.
https://www.stereophile.com/content/jvc-xl-z1050tn-cd-player

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