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Yes, with the beginning of winter and the holiday season almost upon us, the January 2018 issue of Stereophile has started dropping into mailboxes, being displayed on newsstand shelves, and being downloaded to tablets. And it is, even if we say so ourselves, one heck of an issue, with GoldenEar's Triton Reference speaker on its cover and reviewed inside by John Atkinson. JA also kicks off the issue with a look at the controversy raised by MQA. Controversy? Also in the January Stereophile, Jim Austin examines the time-domain performance of MQA-equipped DACs and one Internet troll is already…
Tuesday, December 12, 2–7pm, New York retailer In Living Stereo (2 Great Jones Street, Manhattan, NY 10003) is holding a special headphone event featuring the entire line of Audeze headphones, Woo Audio tube headphone amplifiers and the Hugo TT, Mojo, and new Poly wireless streamer for the Mojo from Chord Electronics.
Jack Wu from Woo Audio, Evan Grimm from Audeze, and Richard Colburn from Chord Electronics will be there to talk technology and answer questions. There'll be snacks available as well as "great coffee" from In Living Stereo's Darkstar Coffee shop.
"The fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected at another point."—Claude Shannon
Since its announcement at the end of 2014, Master Quality Authenticated, the MQA encoding/decoding system, has spawned outspoken criticism. Some of the more thoughtful negative reactions have come from engineers such as Dan Lavry, Bruno Putzeys, and Daniel Weiss. Others have been expressed by manufacturers of digital products: the late Charley Hansen at Ayre Acoustics, for example, along with Jason Stoddard and Mike Moffat at…
I don't think I've ever seen an audio debate as nasty as the one over Master Quality Authenticated (MQA), the audio-encoding/decoding technology from industry veterans Bob Stuart, formerly of Meridian and now CEO of MQA Ltd., and Peter Craven. Stuart is the company's public face, and that face has been the target of many a mud pie thrown since the technology went public two years ago. Some of MQA's critics are courteous—a few are even well-informed—but the nastiness on-line is unprecedented, in my experience.
It's reasonable to be concerned about MQA. It's a big deal. There's already much…
Manufacturers' Comment
Editor: Thanks for the Follow-up and the chance to comment on Jim Austin's discussion of MQA's time-domain performance.
The graph in Jim's fig.4 shows the result of converting the MQA file directly to analog without a decoder. The text describes it as ". . . mostly linear-phase, though the asymmetry suggests some nonlinearity in the phase response. . ."
If we look at the 48kHz MQA test signal waveform (fig.1 in this comment), there is no pre-response. It is elegant that the decoder "unfolds" it back to a perfect impulse as we can infer from Jim's…
I first learned of the Kuzma Stogi at the 1993 Winter CES in Las Vegas. In VPI's room at the Sahara, a portly, black tonearm was sitting proudly atop the new VPI TNT Series 3 turntable. Pointing straight at me from the center of its massive, exceptionally stout frame was a tapered armtube the diameter of a swollen thumb. The fact that this unknown (to me) tonearm was chosen to sit atop a turntable as respected as the TNT told me I was looking at a serious new product. VPI's Harry Weisfeld was standing nearby, beaming as usual, to answer the barrage of questions that sprang from my lips as I…
The Stabi's substantial dustcover is easily removed, though after playing records with and without it and hearing no appreciable difference in sound, I left it on and down for all subsequent listening sessions.
Sound
I was totally unprepared for the magnitude of difference I heard between my longstanding reference WTT and the newly installed Kuzma. Every sonic parameter that I placed stock in in assessing the performance of the WTT was redefined by the Kuzma. To say I was astounded would be an understatement. By the end of the first day of listening, I also felt the early tinges of…
Sidebar 1: Guy Lemcoe's System
Before the Kuzma arrived, my analog reference was a fully tweaked Well Tempered Turntable and the superlative Roksan Shiraz MC cartridge. In the course of this review, I also had occasion to listen to two new entries in the under-$1000 MC cartridge sweepstakes: the Dynavector Karat 17D2 Mk.II and the Benz-Micro Glider. Since I'm currently in the middle of a survey of phono preamps, I had a variety on hand from which to choose: Ensemble's Phonomaster, Rotel's RHQ10, Sonic Frontiers' SFP-1 Signature, and, most recently, Michael Yee Audio's PFE-1. I relied…
Michael Fremer auditioned Kuzma's "S" upgrades in July 1999 (Vol.22 No.7):
The Kuzma Stabi S turntable originally caught my eye at the 1998 Heathrow Hi-Fi Show. My experience with the Simon Yorke Designs Series 7 turntable has convinced me of the potential of a plinthless 'table, and the Stabi S confirms it. The platter-bearing assembly is sunk into a heavy, solid brass tube that also holds the arm. A smaller, stabilizing hunk of solid brass tubing with O-ringed training wheels (just being colorful; these wheels don't turn) is affixed at a 90° angle. A nicely machined aluminum…
Sidebar 2: Specifications
Kuzma Stabi: suspended subchassis, belt-drive LP turntable. Speeds: 33.33rpm, 45rpm. Plinth: solid oak. Subchassis: Medite. Platter: 9 lbs. mass, precision-machined solid aluminum. Removable dustcover: smoked glass in solid-oak frame. Resonance of subchassis: 4.7Hz. Motors: one, 24-pole synchronous, 110V, 50Hz. Speed adjustment: ±0.5%. Power supply: external, quartz-controlled.
Dimensions: 7¼" H (with dustcover closed) by 201/8" W by 161/8" D. Weight: 46 lbs.
Price: $2200 (1995); $1200 (1999).
Kuzma Stogi tonearm: Construction: main assembly and…