First Watt F7
For over fifteen years First Watt has served as Nelson Pass’ creative playground, allowing him to explore unusual low-power designs with an emphasis on sound quality. The F7 is intended as an improved version of the popular F5, a 25Wpc stereo push-pull Class A amplifier. What makes the F7 so special is its inherent textural sweetness and warm tonality. There are many solid-state amps out there that manage to sound smooth and refined yet lack the organic character of live music. The F7, on the other hand, manages to sail through reproduction of violin tone with superb upper-register sheen and transient finesse—a rare feat for any solid-state amplifier—while its command of space is competitive with the sort of 3-D spatial presentation tube amps excel in. Simply put: one of the best low-power amps money can buy.
Using Primare’s proprietary UFPD (Ultra Fast Power Device) switching technology, the Primare A34.2 delivers tremendous speed and plenty of power (150Wpc) in a relatively compact, light, and affordable package. Although the A34.2 is certainly capable of slamming hard, driving Magnepan 1.7s with ease, it is also capable of fine resolution and finesse. The stereo A34.2 can be bridged into mono operation for 550W into 8 ohms. Overall, the A34.2 handsomely meets Primare’s design goals for a powerful, ultra-fast, almost noise-free, and pretty neutral amplifier that can easily slip into essentially any stereo or multichannel application.
Audio by Van Alstine FET Valve 600R
What sets Frank Van Alstine’s 300Wpc tube/transistor hybrid amp apart from a host of other hybrid designs is its soulful midrange and ability to retrieve music’s drama and tension. Tack on decent spatial delineation, low distortion, superior speed, killer bass, and superb dynamics, and you have world-class power amplification at an affordable price.
Wyred 4 Sound SX-1000R
While many amplifiers use Bang & Olufsen’s ICE switch-mode output module, the SX-1000R combines it with its own direct-coupled, balanced, dual-FET input stage, designed by Bascom King. The SX-1000R’s 625W of power (1225W into 4 ohms) can effortlessly deliver copious dynamics and details. Imaging through the SX-1000R is laterally precise. If you require a power amplifier that can generate oodles of effortless output, runs cool, produces a very precise lateral soundstage, offers substantial bass extension and control, has a neutral harmonic balance, and is exceedingly quiet, the Wyred 4 Sound SX-1000R should be on your short list.
Atma-Sphere S30 Mk 3.3
The Mk 3.3 version of this 30Wpc Circlotron OTL amplifier nudges performance higher in dynamics and soundstage transparency. Although guilty of slight timbre alterations and a somewhat dark tonal balance, these acts of commission, likely due to load interactions, point out the need for a compatible loudspeaker and front-end electronics. The S30 strikes an intelligent balance between quality and quantity, focusing as it does on delivering a strong first watt. Its asking price is a small price to pay for a generous slice of musical heaven.
Bel Canto Ref600M
To SS’ ears Bel Canto’s 15.4-pound, 300W (600W into 4 ohms) Ref600M Class D monoblock is good enough to qualify as the best all-around power amplifier he’s heard to date, regardless of technology or circuit topology. Its combination of extremely low noise that makes it suitable to drive even highly efficient loudspeakers, precision three-dimensional imaging, relaxed and natural harmonic balance, and power capability, makes for a potent package. Couple all its sonic achievements with its relatively modest price and you have a power amplifier that could well be a benchmark reference for many audiophiles for years to come.
The sixth version of this most classic of all McIntosh amplifiers is by far the best, boasting greater tonal neutrality yet without losing the beautifully solid, rounded, dimensional, and natural musicality of its tube origins. Thanks to improvements in the transformers, distortion and noise are far lower than ever, bandwidth higher, dynamic range wider, transparency greater, and transient response better than ever. At 75Wpc (though 90 is typical), the 275 has virtually all the power PS needs, but for those who want more, it’s strappable to 150W. Whether used alone or with the C22 preamplifier, the MC275 makes utterly fabulous music and its traditional looks make it, like the C22, a feast for the eyes as well as the ears.
The Magtech “sounds as if it has infinite power into anything with total stability,” says REG. The fully regulated power supply is unusual. The rated power output of 500Wpc into 8 ohms and 900Wpc into 4, coupled with its stability driving capacitive loads, makes it the perfect choice for electrostatics.
Linear Tube Audio/Berning ZOTL40
The ZOTL40 was commissioned and licensed directly from David Berning, and in many respects, is similar to the ZH-230. This is nominally a 40Wpc power amp based on Berning’s patented impedance-matching technology that does away with a conventional output transformer. Expect a substantial dose of tube magic with a good measure of tonal neutrality. There’s just the right touch of harmonic lushness delivered with superb transient speed and control. Reproduction of the treble range, in particular violin overtones, is grain-free and effortless and does much to enhance long-term listenability.
Coincident Speaker Technology Frankenstein M300B Mk. II
One of the best-sounding 300B SET amps DO has auditioned, Israel Blume’s Frankenstein IIs deliver on the promise of SETs: a midrange to die for, wonderful tonal color saturation, and spectacular imaging. In short, a sensational first watt! Its combination of affordability and performance makes for a screaming buy recommendation with the right speakers.