Accustic Arts Reference Hybrid Tube Preamplifier II Mk II and Mono II Monoblock Amp

Nimble, Powerful, Artful

Equipment report
Solid-state power amplifiers,
Tubed preamplifiers
Accustic Arts Mono II,
Accustic Arts Reference Hybrid Tube Preamplifier II Mk II
Accustic Arts Reference Hybrid Tube Preamplifier II Mk II  and Mono II Monoblock Amp

As heretical as it may sound, there is audio equipment that looks so attractive that sonic considerations can take a backseat, at least until you actually listen to it. The Accustic Arts gear falls firmly into this camp. Its fit and finish aren’t just appealing; they’re breathtaking. A friend of mine wanted to want to buy them based on their looks alone even before he got a chance to hear them.

The good news, however, is that the Reference Hybrid Tube Preamp II Mk II—or, as they put in German, “Der Tube preamp”—and Mono II not only look fetching but also deliver the musical goods.

As the bilingual instructions in the owner’s manuals indicate, Accustic Arts hails from Germany. Put bluntly, there is no wiggle room on products made in Germany. Germany is, of course, getting a lot of press these days for its phenomenally successful small and mid-sized businesses known as the Mittelstand that form the fiscal backbone of the country’s economy. Accustic Arts fits right in with that ethos of quality and performance.

The Accustic Arts equipment appears to be bulletproof in both reliability and performance. As its name suggests, the Hybrid Preamplifier features a mix of tubes (two 12AX7s per channel) and transistors. The unit is truly balanced from input to output, with four separate signal paths (left +, left –, right +, right –) and a four-element potentiometer to control the volume. A front-panel button allows you to choose between direct-coupled (no coupling capacitors between stages) and AC-coupled operation (coupling capacitors between stages), depending on which sounds best in your system. Three balanced and two unbalanced inputs are provided. Two variable-level outputs are included for bi-amping. A third output, this one a fixed level, can drive an outboard headphone amplifier (although the Hybrid includes a front-panel headphone jack). A theater “pass-though” allows the preamplifier to be combined with a multichannel system.

The same sort of thoughtful design appears to have gone into the power amplifier. It’s pure solid-state, delivering 300W into 8 ohms and 500W into 4 ohms via 12 MOSFETs in each amplifier’s output stage. It effortlessly powered both the Magnepan 3.7i and Wilson XLF loudspeakers. The amplifier’s diminutive size belied its power, which pretty much appeared to be limitless on either speaker—and any amp that can drive the Maggies isn’t whistling “Dixie!” The amp features a protection circuit that will trip if the amp is clipping, or if it detects DC offset from the preamplifier, the latter phenomenon something that can crater your loudspeaker’s drivers.

On both digital and vinyl I was impressed by the preamp and amp’s silky midrange and the wealth of detail they produced. Mated together, they definitely supply a sound that lands firmly on the tube side of the sonic spectrum. The preamp is a balanced hybrid design that takes several minutes to warm up. I would emphatically suggest that the amp needs several hours before it sounds its best. Upon startup it will appear to be a bit grainy and compressed. These qualities vanished after a few hours.

In keeping with the balanced design, I used a pair of Ypsilon transformers to create a balanced signal from the cartridge on my Continuum Caliburn turntable to drive the preamplifier’s balanced inputs. From the dCS Vivaldi I used Nordost Valhalla 2 cabling, as I did for the speaker cables as well. The balanced design helped to ensure that there was no audible noise or hum. In fact, even when I ran the amplifiers in single-ended mode from the Ypsilon preamplifier, I was pleased to note that there was also no hum or buzz. Accustic Arts gives you the option of switching off the tubes via a button on the front panel to save on precious tube life.

Like most manufacturers, Accustic Arts makes much of its wide bandwidth and low distortion, and those qualities were in evidence on both CD and vinyl playback. The equipment sounds extremely linear with no part of the frequency spectrum appearing to be overemphasized. It is this very linearity that may strike some listeners as producing a sound that is staid, but it is not. Rather, the Accustic Arts equipment is non-fatiguing and engaging, though it definitely has its own sonic hallmark.