The 36Wpc vacuum tube-powered ProLogue 5 is more authoritative than its rating would lead you to expect, and offers a warm, rich presentation, yet really does not sound “tubey” in any traditional sense, producing clean, deep, tight bass and grand soundstaging. A synergistic match with the companion ProLogue 3 preamp.
Reviewed by SR, Issue 156
They may not be fully twice as good as the Khartago stereo amp (see above), but they’re mighty good, improving on the Khartagos in every area (particularly in stereo separation and lower noise). Once again, champagne sound on a beer pocketbook.
The hybrid SP-331MK delivers 150Wpc into 8 ohms and 300Wpc into 4 ohms, and operates in pure Class A for its first 10 watts. This makes the amplifier somewhat dual-natured, in that at moderate levels it sounds spacious, naturally balanced (if a tad dark), with good dynamic scaling and fine rhythm and pace. Pushed harder, and its tonality turns grayer, strings get a bit ragged. Overall, a terrific design that seems happiest when not pushed all the way to its power limit.
Reviewed by WG, Issue 208
An excellent Class AB stereo transistor amp, designed by the redoubtable John Curl, capable of 250Wpc into 8 ohms (400 into 4 ohms). Though not the last word in solid-state amplification, the A21 offers a lot of power at an affordable price.
Reviewed by JV, Issue 168
While many amplifiers use Bang & Olufsen’s ICE output device, the SX-1000 combines it with its own direct-coupled, balanced, dual-FET input stage designed by Bascom King. A powerful amplifier capable of effortlessly delivering copious amounts of power, the SX-1000 Series II serves up detail with the aplomb of a sommelier uncorking a prize bottle.
Reviewed by SS, Issue 193
This tube monoblock combines a rich treble and midrange with a gutsy, controlled bass and a clarity unusual in its class. Its one shortcoming is a tendency to push the midrange a bit forward. Even with this, it makes all types of music sound right.
Reviewed by SR, Issue 171
These beautifully built, affordable, and “hassle-free” 70Wpc monoblocks will alter your preconceptions about tube gear. Indeed, their transient quickness and ability to drive difficult loads may fool you into thinking you’re listening to a very good hybrid. Yet they still have that wonderful tube magic.
Reviewed by JH, Issue 169
The key to the 200Wpc 840W is its proprietary XD topology, which allows pure Class A at low levels and a transition to an “enhanced” Class B without the crossover distortion of Class AB designs. The result is a wide soundstage, excellent micro-dynamics, and near limitless power—plus that familiar, buttery, pure Class A vibe. The acoustically damped, satin-smooth casework is absolutely first-rate.
Reviewed by NG, Issue 186