2023 Editors’ Choice: Best Power Amplifiers $6,000 – $10,000

This 25Wpc push-pull Lux is about triode sweetness. Think of it as a modernized version of the MQ-60 from 1969. Expect naturally sweet, clear, and transparent tonality. Female voice benefits from its textural purity and ability to depict subtle tonal shadings. The harmonic distortion spectrum is benign and devoid of the upper-midrange glare endemic to pentode push-pull amplifiers. Microdynamic expressiveness is also a strong suit and a key factor in nudging listeners over the line from “liking” this amp to “loving it.” A nearly perfect introduction to the joys of triode sound and a superb match for the Quad ESL-57. DO, 297

Anthem’s STR amplifier is a muscular yet stylish component that outputs 400 watts into an 8-ohm load, 600 watts into 4 ohms, and 800 watts into 2 ohms; there aren’t many loudspeakers that this dual-mono design won’t readily control. The dual-mono, 65-pound STR features a proprietary input circuit that Anthem calls “a complementary active-loaded cascoded feedback arrangement.” Right out of the box, the STR impressed with immediacy, detail, and authority of presentation with all kinds of music. Spatiality and low-end weight were excellent, and there certainly was no question of the STR running out of steam with the most dynamic recordings. Solidly built, great sounding, and a high value. AQ, 298

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. DO, 228 (Mk.II version reviewed)

The sixth version of this classic McIntosh amplifier 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. PS, 266

This lithe monoblock amplifier is a happy marriage of old and new technology. It boasts a tubed input stage and a Class D output stage that packs colossal power. With 600 watts into an 8-ohm load and 1200 into 4 ohms, it can drive pretty much any loudspeaker with aplomb. And it does. There are few, if any, amplifiers that will grip the bass drivers as tenaciously as the M1200. Its transient speed can only be described as stunning. The treble region can become a little bright, but the overall performance that the Stellar offers is truly stellar. JHb, 313

David Berning’s Ultralinear (UL) amplifier breaks new ground in emulating a traditional UL output in a ZOTL setting. It also marks the resumption of his “love affair” with TV sweep tubes. A pair of 17JN6 Compactrons in push-pull connection generates 20Wpc. Sonically, the UL has much in common with the legendary ZH-270. Both share transient speed and control beyond the capabilities of ordinary tube amps. Other common denominators are electrostatic-like midrange clarity, which allows for resolution of densely layered orchestration. The best-sounding low-power push-pull ZOTL amp Berning has designed to date. DO, 305 (New “+” version not yet reviewed)

Atma-Sphere’s uniquely simple, 60Wpc, Class A, all-tube OTL (output transformer-less) design offers a rare and exhilarating glimpse into music that few other amps can duplicate. This triode-based classic also possesses outstanding neutrality, clarity, definition, soundstaging, and dynamics. Relatively high-impedance, high-sensitivity speakers are recommended for best bass performance. Sue Kraft, 184

VTL’s ST-150 is a relatively compact yet powerful stereo power amplifier employing 6550 tubes that can drive a wide range of speaker loads. A classic all-valve push/pull power amp, the 150 delivers 150Wpc in tetrode mode and 70Wpc in triode operation. Sonically the amp delivers plenty of wallop, but is also capable of fine dynamic shading, excellent resolution, and great overall coherence, with the attendant bloom, air, and texture tube lovers desire. WG, 251

The fully discrete, direct-coupled Class AB amplifier (with a circuit derived from the company’s much more expensive No534 amplifier is rated at 135Wpc into 8 ohms (270Wpc into 4 ohms) but sounds like a much more powerful amplifier. The bass, in particular, has greater dynamic authority and extension than that of many amplifiers with higher output power. The amplifier excels at reproducing transient detail. AHC, 322

Sounding more like a fine linear amp than the hybrid-switching amp it is, the 180Wpc C21 offers much of the sweetness, air, and texture (if not the full measure of swat) of MBL’s own Reference line 9011 amps. Its top end, the region where Class D once struggled, is smooth and extended. Its lows are elegantly controlled but not over-torqued; instead, there’s a bit of velvety bloom. An amp that can proudly stand next to the best in its class. NG, 228