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Gino neither is nor has to be quitting his part-time trade-school teaching job. The couple has no ambitions or illusions about turning into a big outfit. They don't need audio to survive. It's mostly a love affair. Handcrafting exclusive low-volume artisanal valve audio in Switzerland à la Audio Consulting and Da Vinci Audio Labs is quite different from Nagra's game. Incidentally their push/pull 300B amp with solid-state drivers is a direct competitor and twice as powerful. Entering Nagra's world—which is heavily subsidized by the Kudelski Group corporate colossus of which Nagra Audio is a tiny subdivision—differs once more from shopping top Sino brands like Eastern Electric, Melody or Cayin.

The Colombo system at home
Everything has its place, everything its target audience. One simply remembers that higher prices don't automatically reflect commensurately better (if better at all) performance. Luxury tags need not mirror any reasonable multiplication factor of raw build cost. There's always room for what the market will bear. There's the object d'art angle. And let's not forget crass snob appeal. This plays to the notion that 'best' must mean buttock-clenching sticker shock to be real. For reviewers, personal comfort based on what one considers fair (and how one's own lifestyle educates buying decisions in general) factors into all of this inextricably.

It explains why, when Kamzy CEO Lars Dam emailed me about reviewing their Dutch KAAM-800 or KAAM-1000 valve amps whose €50.000 tags include gold plating, I was out. Personal limitations intruded. I'm told however that our Polish collaborator Wojciech Pacuła is made of sterner stuff. A Kamzy review thus might appear in these pages sooner than later.


Enough shekelanigans now. If you've read this far, you plainly need no advice on how to spend your money; or be told that 10wpc of output power imposes very real limitations in speaker choices; or that EML glass isn't cheap to replace when the time comes. All that is boring boiler plate stuff. Let's inspect the Swiss monos more closely now and learn what specific design decisions Gino Colombo made in his quest for best subjective performance.

The lack of bias adjustments shows that just as with Yamamoto amps, the meter only confirms operational output tube fitness. There's no doubt when exactly the 300B fails to bias up properly. The DC current needle wants to sit at 80mA. At 60mA the tube has tired to need replacing. But this really is plug 'n' play auto bias sans trim pots.


"The circuit is a minimalist 2-stage concept with two direct-heated triodes for voltage and current gain. The 20A driver is choke loaded, then coupled to the 300B via a high-quality Mundorf silver/gold oil capacitor. The iron on deck consists of a power transformer, an EI output transformer with Z9 silicon steel core and a high-voltage filter choke. The Lundahl anode choke for the driver bottle sits below deck. So does a Lundahl 7901 dual-coil stepup transformer with a 1:3 ratio, i/o Ω of 1.1K/10K and extreme level capability (+34dBU @ 50Hz) with two primary and two secondary windings per coil separated by electrostatic shields and a high-permeability mu-metal lamination core.


"All filaments are DC heated and RCRC filtered. Residual hum is ca. 50mV. Input sensitivity is 1.5Vrms and optimized for high-level outputs. My choice of auto bias was due to convenience, intensive auditions and the fact that the EML tube is of such high quality that auto bias doesn't incur the usual compromises."


As it happened, my friend Dan took up the Colombos for a home audition in his house near Lausanne. He wished to hear how their monos would do on his 100dB field-coil Voxativ Ampeggio Dué speakers. His office system runs the smaller Voxativ Ampeggio from a Yamamoto A-010 SET followed by a Burson 160 transistor amp set to current-buffer mode. Sources are an Esoteric UX1/APL Hifi NWO4.0SE and Human Audio Libretto HD. Dan was looking for Yamamoto-type sound with more power than the VT-52s' 3 watts. He wanted a tube option to alternate with the Devialet D-Premier that's already in his big system. Like me he much favors a 45, 46, 50 or VT52 over a 300B. Just so he was intrigued by my impromptu assertion. These Swiss had not sounded anything like typical 300B amps during my first quickie session which had booked this review. As some of his inventory shows, Dan's tastes and mine overlap more often than not. Thus on a Friday morning in early July the Colombos and team Ebaen met at Dan's for a dégustation, potential sale in the wings. I'd be able to report on noise floor and sonics with 100dB speakers regardless and add useful data to those I'd subsequently generate in my own home with my own speakers and sources.

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