So far, the Technics scheme I’ve described successfully relocates volume control and digital conversion to the amp. But what about overcoming the inherent complexities and sonic degradations of standard DACs? The SE-R1 solves this issue by rejecting traditional amplifier topology altogether. Indeed, this is not a traditional Class A, Class AB, or even Class D amplifier. Rather, it is a rare breed known as a “digital” amplifier.
Digital amplifiers are designed to be fed directly by digital rather than analog signals. They make direct use of this signal—without any DAC circuitry whatsoever—to drive the power stage. (See Robert Harley’s sidebar, which explains the operation and benefits of digital amplifiers.) In effect, the amp “natively” converts digital to analog as an inherent part of the amplification process.
As already noted, the SE-R1 also has analog inputs, allowing its use as a traditional power amp. In that case, the first thing the SE-R1 does to inbound analog signals is to convert them to digital. This is handled by the same high-quality, 192/24 A-to-D converter that’s used in the SU-R1 to take in analog sources such as phonostages.
The R1 Components Independently
In the main review I’ve described the R1 system as a whole because that’s how it’s intended to be used. However, I was curious about how the individual components would fare. So I compared each to its counterpart in my reference system. Other than the speakers, this was—based on price, at least—an unfair comparison. What I found was that each element of the R1 system can hold its own against far more expensive gear.
The SU-R1 streamer/DAC sounds remarkably similar to the CH Precision C1 (about $40k). Both offer deep resolution, great timbral detail, and snappy rhythms. Also like the C1, but unlike several other units I’ve reviewed recently, the Technics fares very well in streaming mode. Though it is not quite as tonally colorful as its other inputs, networked music sounds every bit as incisive and dynamic. Compared to the C1, the SU-R1 gives up a little refinement, but is more open and lively. Similarly, the Technics isn’t as dynamically boisterous as the C1 (not much is, really), but it boasts tighter, more convincing imaging. Still, unsurprisingly, the SU-R1 always sounded its best when routed through the SE-R1.
For its part, the SE-R1 exhibits the same bold dynamics, staggering detail, and sheer volume of musical information I’m used to getting from my reference CH-Precision A1 monoblocks. Remarkably, this is true even when the Technics amp is being driven by its analog inputs. The sound from both amps is gloriously rich, pure, and grand when the music calls for it. The biggest difference is actually in the Technics’ favor: a more realistic-sounding midrange, thanks to a dollop of sweetness.
The SB-R1 speakers are a somewhat different story. Although lovely sounding, admirably extended and as dynamic as you’d ever want, as I’ve already noted they benefit significantly from LAPC. Furthermore, I tried driving these speakers with other amps and quickly ran up against their capacious thirst for current. Even the CH A1 monoblocks couldn’t drive them fully. For these reasons, I recommend the SB-R1’s be used with their intended power companion. In that setting, although not as lively as my reference speakers, the SB-R1’s are more refined and offer more extended lows.
Digital amps haven’t taken hold in the high end, but as Robert describes, they have major advantages for digital sources. Perhaps, given the rise of hi-res material and streaming, their time has come. In any case, once Technics settled on such a device, the company set out to build the most advanced version ever made. An example of that advancement concerns jitter. A digital amplifier’s direct signal path means that the incoming signal’s purity is paramount. And, as with all digital signals, jitter is the bane of that purity. Accordingly, Technics developed a proprietary module, called the JENO Engine, to clean up jitter and move noise out of the audible band. JENO is the first thing the incoming bits hit.
Another gain involves the driver stage. Typically, popping the lid on a high-powered solid-state amp reveals banks and banks of output transistors. As it had with so many industry-standard approaches, Technics found fault in this one. Those parallel transistors are prone to noise associated with timing differences, capacitive imbalances, and stray inductance. To eject this noise source, the SE-R1 incorporates a gallium-nitride (GaN) FET drive stage that’s so efficient it requires just one “push” and one “pull” transistor for each “+” and “-” terminal. No parallel output transistors.
The second “intersection” between components is bookended by the amp and the speakers. This is where we can turn our attention to that mysterious button labeled LAPC. Load Adaptive Phase Calibration sounds gimmicky, but it’s actually a succinct description of the button’s function. LAPC is intended to counteract the fact that a speaker’s impedance varies by frequency, which in turn generates phase shifts and presents a less than ideal load to an amplifier. The situation is all but unresolvable with an analog amp; but, conveniently, the SE-R1 operates in the digital domain. There, it can use DSP to optimize the amp’s amplitude and phase characteristics for the specific speaker attached.
Setting up LAPC is a breeze. Hold down the button and the amp begins squirting out sonic bleeps, blips, and bloops into one speaker at a time. The entire process takes a couple of minutes. When it’s done, the sonic transformation is not subtle. The exact nature of that transformation depends on the particular speaker attached. For instance, before LAPC, the Technics SB-R1 speakers struck me as too mellow, with bass that was bit plummy for my taste. LAPC straightened them right up, adding snap to attacks, which yielded greater rhythmic drive, and neutralizing the plump bass. On the other hand, my reference Metaphor 1 speakers had the exact opposite problem: too edgy. LAPC addressed that issue, bringing composure to the highs. No wonder Karl Schuster took to calling LAPC the “magic button.”
Equally remarkable, however, is something LAPC seems to do for every speaker, which is to flesh out the three-dimensionality of instrumental images. Jonathan Valin recently observed—and I concur—that image dimensionality remains one of the last distinctions between good tube and solid-state electronics. Specifically, whereas glass can conjure a convincing 3-D image of an individual instrument, transistor images tend to be flat. Perhaps, then, it is LAPC’s uncanny ability to inflate images like a balloon, combined with the SE-R1’s simple, direct signal path, that explains why this is the most tube-like solid-state amp I’ve heard.
Notice that all this fancy technology is designed not to enhance sound but rather to remove unwanted artifacts. The SU-R1’s Direct mode clears away extraneous circuitry, while its battery-powered clock eliminates noise and timing perturbations. The Digital Link combined with the SE-R1’s PWM topology completely obviate the need for a traditional DAC. LAPC wards off phase-induced distortion and the JENO engine mitigates jitter. The GaN FET abolishes the artifacts associated with banks of parallel output transistors. Even the SB-R1 speaker, with its flat coaxial driver and point-source layout, is designed to battle dispersion irregularities. In short, the R1 system’s mountain of technology is all directed to the singular purpose of simplifying and purifying the signal path.
And that’s as good a way as any to describe the R1 system’s sounds: direct and pure. Like an inviting pool on a summer day, there’s nothing to obscure your ability to dive into the music. There are virtually no tonal imbalances, no inability to keep up, no slurred transients, no compression, no flattening, no distortion, and no strain. Listen to a recording like Charles Mingus’ Ah Um and hear how effortlessly the R1 system conveys its challenging rhythms, dynamics, and harmonics. On more serene pieces, like the Reiner/CSO recording of Debussy’s La Mer, the system changes character to become—like the music—spacious and ever so gently emotive.
Nor does the R1 system neglect the frequency extremes. Thanks to the SE-R1’s massive current delivery and all those woofers in the SB-R1, lows are solid and assured, with no evident extension limitations. If the music calls for gutsy, air-shoving oomphs, like the walloped timpani on the Pentatone recording of Stravinsky’s L’Histoire du Soldat, this system has no problem delivering. Tonally, the bass is naturally warm.