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The EAR V20 left Chip Stern's New York apartment in pristine condition, but by the time it arrived at our Santa Fe offices there were visible signs of shipping damage, including dents in one of the protective tube cages. Nothing in the following measurements, however, suggests any operational damage or degradation.

In normal operation, the cages surrounding the EAR V20's tubes get quite warm, but never uncomfortably hot. It's likely that the lower-than-normal operating temperature is due to the choice of multiple small, low-power output tubes in place of a…

Would that things were…

If, in digital audio, one doesn't pay a similar amount of attention to characteristic impedances when connecting two pieces of equipment, jitter will occur....The amount of jitter caused by impedance mismatching is admittedly small, but some simple arithmetic may clarify the situation. If, in the final digital/analog conversion, we do not tolerate more than 0.5 LSB of amplitude error (vertical axis), neither should we accept a greater error along the horizontal axis (time)....Vertically there are 65,535 steps in a 16-bit…

There's one thing I enjoy about single-ended triode amplifiers, although it isn't so much a characteristic of a good SET as the combination of a good SET amp and an appropriate loudspeaker: They load the room convincingly when the music demands it. It's a hard thing to describe, but I know it when I hear it, like open fifths or pornography. And it can be subtler and less bombastic than you might guess—like the first piano chord in Schubert's "Trout" Quintet: There's a manner in which the sound of that…

Well, for one thing, there's serious potential for unfairness. If I open my home to Company A, then I'll have to do the same for Companies B through Z as well. I've heard complaints about this more than once from manufacturers who…

Only problem is, that ol' valve…

Description: Stereo hybrid tube/solid-state power amplifier. Rated power: 35Wpc (15.44dBW/8 ohms), 30Hz-21kHz, at less than 0.3% THD or IM. Input sensitivity: 1.15V. S/N ratio: >100dB.
Dimensions: 16" W by 12" D by 7" H (including tube height). Weight: 30 lbs.
Available cabinet finishes: oak, walnut, cherry, mahogany, maple, and black lacquer at no additional cost.
Price: $1695 (1992); no longer manufactured (2004). Approximate number of dealers: 43.
Manufacturer: Nobis Technologies, W141 N9316 Fountain Blvd., Menomonee Falls, WI 53051. Tel: (414…

I hooked the amps up to my hi-fi rig: Aunt Corey's Homemade Buffered Passive Preamp, Audio Research SP-14 phono stage, Well-Tempered Record Player fitted with the Sumiko Blue Point cartridge and Analog Survival Arm Wrap, the Proceed CD Library 100-disc multi-player, Theta DS Pro Basic II processor driven via Theta's excellent digital cable by either a JVC XL-Z1050 CD player or the dig-out jack of the CD Library, and ProAc Response Two speakers seated on the back-breakin' heavy-metal Target RS2 stands. Interconnects were Kimber KCAG except for Straight Wire Maestro between…

The Nobis Cantabile ran quite warm after its preconditioning test, but not enough to cause concern. As with all tube amplifiers, it runs quite warm in any case. Its operation was non-inverting, and though it appeared to have some 1/f noise present on its output, this was generally under 10mV and is not something to be concerned about. The unweighted, wide-band S/N ratio measured 65.6dB, referenced to 1W into 8 ohms.

The input impedance of the Nobis was, like many tube amplifiers, quite high: over 320k ohms, making it an easy impedance match for most preamplifiers.…