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Listening #58
Is it my imagination, or has the low-power tube movement of the last 15 years gone hand in hand with a renewed interest in moving-coil step-up transformers? Trannies remain misunderstood or ignored by most of the audio press—requests for review samples continue to be met with genial shock, rather like tourism in the Budapest of the 1990s—but enthusiasm for the practice seems only to grow. That leaves me to wonder: Did the unquestioning use of active pre-preamps for so many years grow out of the same bad attitude that gave us all those awful-sounding high-power amps and low-sensitivity loudspeakers? You know the mindset: Parts are cheap. Gain is free. Do it because you can...
Footnote 1: From drummer Stewart Copeland's blog: "We are so off-kilter that Sting counts us in to begin the song again. This is unbelievably lame." Indeed.
Maybe the hobby is just coming full circle, as most things do. Maybe 20 or 30 years of making tube amps is enough to open a designer's mind to other good things. (Activity time: List the best names in amplifier design, then circle the ones that also offer step-up transformers.) Maybe some of us are responding, subconsciously or not, to the poetic symmetry of a system in which a transducer is directly connected to a transformer at both ends.
Whatever it is, the results speak for themselves. Just as a good single-ended amp and high-sensitivity loudspeaker can't be appreciated without an analog front-end, neither can they be heard at their best without a step-up transformer at the source.
Now, for only $275, you can move a step closer to knowing for yourself. That's the price of the kit version of the K&K Audio step-up transformer I wrote about last month; the assembled version sells for only $335. I know you hate it when spoiled audio reviewers use the word only in sentences that contain dollar signs, but this time I feel justified: $335 is less than the price of a pair of main concourse tickets to see the Police on tour last summer—and by all accounts, even their own, they sucked out loud (footnote 1).
I've been listening to the K&K step-up transformer for a couple of months, alongside a selection of other moving-coil trannies with prices ranging all the way to $8675, and thought you'd like to know about the performance differences that exist within that spectrum. I also thought you'd like to know which MC phono cartridges worked best with which trannies. To that end, I used a fairly wide selection of the former:
Miyabi 47 ($3950): There are so few windings in the coils of this handmade cartridge that you can easily count them for yourself. Consequently, and notwithstanding designer Haruo Takeda's use of a powerful alnico magnet, the Miyabi 47 has a low output (0.3mV) and low source impedance (2 ohms). This medium-low-compliance design is the most dynamic, dramatic, and downright exciting cartridge I've heard to date.
Koetsu Black ($1600): An enduring design with slightly higher output (0.6mV) and impedance (5 ohms) than the Miyabi, but that still qualifies as a typical low-output cartridge, the Koetsu Black is colorful and lush, with lots of body, and it's impressively quiet in the groove. Medium-low compliance. (Reviewed in the July 2007 issue.)
Benz-Micro MC20E2-L ($199): An unusual combination of low output (0.5mV) and high impedance (32 ohms), this low-compliance cartridge is a nice all-arounder with especially good dynamics. Its best quality, however, may be its crazy-low price. (Reviewed in the September issue.)
Denon DL-103 ($229): Audio maven extraordinaire Garth Philippe, who passed away in July, was among the most eloquent proponents of this simple, reliably musical device. (So, for that matter, is friend and fellow Listener alum Rob Doorack.) Gray-market samples were all we could get for a while, but thankfully the DL-103 is once again an official part of Denon's US product line. Like Bill Monroe's lost love, the DL-103 gives you body and soul—and it's a hell of a bargain. The Denon has an unusual combination of output and impedance specs, which are 0.3mV and 40 ohms, respectively. Its compliance is quite low, and its stylus profile is conical.
Zu DL-103 ($399): Zu Audio, Utah's other hi-fi company, is becoming known for good-sounding, high-efficiency loudspeakers at less-than-extortionate prices; this is their first foray into the pickup field. Essentially, it's a Denon DL-103 motor that's been potted and planted in a laser-milled aluminum body. Specs as above (and review in the works).
EMT JSD 5 ($2850): Although EMT has scaled back since their glory days, it's a delight just knowing that this venerable maker of domestic and professional playback gear is still around. The JSD 5 is EMT's latest iteration of their basic motor, with virtually the same highish output (1.0mV) and impedance (20 ohms) as always. Compliance is low, and performance is high on drama, force, momentum, and sheer chunk.
A bit of housekeeping before I put those sources through their courses:
• As I mentioned in this space last month, manufacturers' specifications for transformer input impedance usually refer to the approximate source (cartridge) impedance for which that product is suited. Moreover, input impedance and input resistance (DC) are two different things. That said, I've included the input- and output-resistance specs that I've measured here at home, for the sheer reckless fun of it.
• Long ago I borrowed a Koetsu step-up transformer from a retailer friend—it was languishing on a shelf after a kiss-off from a reviewer who obviously knew nothing about trannies and was apparently disinclined to learn. I was astounded at how good it sounded. Some 20 years later I assumed the thing had been discontinued, but new distributor Hiram Toro assures me that the Koetsu Transformer ($3500) is still in the line. Sadly, the review sample didn't arrive in time, so I'll follow up later.
• I tried to borrow a sample of the Mu transformer from the progressive Canadian company Bent Audio, but the model is undergoing revision, and a supplier's delay prevented Bent from shipping one in time for this piece. The original Mu seemed to offer a lot of good engineering for a very reasonable price ($895 for a pair of mono units), so this is a company we should all keep an eye on.
• Finally, in a gaudy display of premature senility, I neglected to request a sample of EAR's new MC4 ($1995) in time to include it here—which is too bad, given that its predecessor, the MC3, was exceptionally flexible and good sounding: testament to designer Tim de Paravicini's depth of experience with all things core and winding. I promise to cover it in a follow-up piece, along with the other two I missed.
Footnote 1: From drummer Stewart Copeland's blog: "We are so off-kilter that Sting counts us in to begin the song again. This is unbelievably lame." Indeed.
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