Reviews of Attainable Hi-Fi & Home-Theater Equipment


Reviews of Attainable Hi-Fi & Home-Theater Equipment


Note: for the full suite of measurements from the SoundStage! Audio-Electronics Lab, click this link.

In a recent editorial about the appeal of vintage audio, I said, and I quote, “Build me a $1500 stereo receiver or integrated amp that looks anything like [the $9500 Technics SU-R1000 stereo integrated amplifier], and I think I could turn a lot more uninitiated music lovers into high-performance audio enthusiasts.” Needless to say, at $2699.99 (all prices USD), the Technics Grand Class SU-G700M2 integrated amplifier isn’t precisely that amp. Still, this new offering promises to be a much more value-oriented alternative to the company’s big-boy flagship, at a price that places it reasonably within the spectrum of attainability for many people, even if they’re not hardcore.

Of course, as its name implies, the SU-G700M2 is not a wholly new product. It is an updated version of the company’s popular SU-G700, which our own Hans Wetzel reviewed a couple of years ago.

Technics

Like its forebear, the SU-G700M2 is a digital amp built on Technics’ JENO (Jitter Elimination and Noise-shaping Optimization) circuitry. Hans did a great job of explaining the technology, so I won’t dwell on it here, but the bottom line is that this all-digital architecture isn’t class D, which is fundamentally analog amplifier technology. And since the amp is fundamentally digital, there’s no need for an integral DAC. Incoming digital signals go straight to the amp’s low-jitter signal rate converter and then into a Delta-Sigma PWM converter, and incoming analog signals are brought into the digital domain by way of a 24/192 A-to-D converter.

The SU-G700M2 also benefits from Technics’ Load Adaptive Phase Calibration (LAPC), a feature that the company says “adjusts the gain and phase frequency characteristic of the output signal potentially influenced by the speaker impedance, and realizes flat gain and phase characteristics at the speaker terminal, regardless of which speakers the amplifier is connected to.”

Technics

So what sets the G700M2 apart from the original model? Unfortunately, the press release and the product website don’t make this super easy to figure out, but Technics’ US business development manager, Bill Voss, explained to me that the new model benefits from an improved phono preamp with support for MM/MC cartridges (the original included only an MM phono stage), as well as a phase-reversal switch (accessible via the menus); improvements to the digital/weak signal block in the phono architecture; an improved phono ground terminal (the same one used on the company’s SL-1200GR direct-drive turntable); and an upgrade to the unit’s AS2PS (Advanced Speed Silent Power Supply), including trickle-down GaN FET and SiC diodes employed in the SU-R1000.

Even if you don’t do vinyl (guilty as charged), the upgrades to the power supply are significant enough to make the SU-G700M2 worth talking about, which is handy for me, as I never got to review the original. And I desperately wanted to, not wholly due to the JENO and LAPC technologies, but, as I hinted at above, largely due to the aesthetics of the amp. The clean silver look—or clean matte black if you weren’t raised right and think that looks better—the simplicity of the front-panel design, the dancing VU meters with their cool-white edge-lighting. All of it triggers some part of my lizard brain that simply thinks this is what hi-fi is supposed to look like.

Technics

Even if you’re not driven by the same proclivities, though, you have to admit the SU-G700M2 is quite well-equipped as digital-focused-but-non-streaming integrated amplifiers go, with two stereo line-level analog audio inputs (one that can be configured as a home-theater bypass input referred to as Main In) in addition to the MM/MC phono stage, two optical digital inputs, two coaxial digital inputs, and a USB Type-B input for PC audio. (I’d normally refer to the latter as a PC-DAC connection, as this seems to be the prevailing naming convention, but since there’s no conventional DAC . . .)

There’s also a Line Out that only functions with the analog inputs (Phono, Line In, Line 2 In), as well as a Pre Out that could be used to connect a subwoofer or, for whatever reason, an outboard power amp. The SU-G700M2’s own amp is likely more than sufficient for most speakers in most rooms, though, given its rated 70Wpc output into 8 ohms (1kHz, 0.5% THD, 20kHz LPF) or 140Wpc output into 4 ohms (1kHz, 0.5% THD, 20kHz LPF). The front panel also includes a quarter-inch headphone jack powered by a class-AA amp.

Configuring and dialing in the Technics SU-G700M2

If I have one criticism of the setup process for the G700M2, it’s that most people will, I think, probably need to read the instruction manual, which seems counterintuitive given the simplicity of connectivity. The issue—I hesitate to call it a problem—is with the unit’s Load Adaptive Phase Calibration functionality, which I fear might be difficult for the uninitiated to understand without digging into the literature. And that’s odd in this day and age, where if you’ve ever set up a stereo component before, you can generally set up any other. But the SU-G700M2 is an exception, and thankfully so is its documentation, in that it’s well-written, well-illustrated, clear, concise, and easy to reference.

I just feel that Technics could have done more to signal the presence of Load Adaptive Phase Calibration on the onscreen display the first time you fire up the amp. The process is represented on the remote control by a button that simply reads “LAPC,” but there’s no button for it on the faceplate of the amp itself (although there is an indicator light). There’s also nothing in that initialism that would indicate to most people that this function has anything to do with tuning the amp to adjust for the electrical profile of your loudspeakers.

Technics

The funny thing about all this fuss is that when you do finally figure out how to run LAPC, it’s an exceedingly simple and straightforward operation. Hold the button on the remote and you’ll start to hear a series of chirps and blips reminiscent of room-correction test tones. But don’t worry—there’s no microphone to concern yourself with. Nothing is actually listening to those test tones. The amp simply needs your speakers to reproduce a series of impulses across the audible spectrum so it can measure its own electrical output and make any necessary adjustments. Pick your system up and move it from Timbuktu to Guadalajara, and there’s no need to re-run LAPC, so long as you’re using the same speakers. The room doesn’t matter. The location doesn’t matter. But if you should swap your speakers out for a new pair, you’ll want to run LAPC again.

In other words, if you’re like me and you almost never use a remote control for your two-channel gear, you should nonetheless keep the G700M2’s wand-style clicker in a safe place so it doesn’t get lost. The remote is also necessary if you want to adjust the tone controls or balance, or tweak the auto dimming or auto standby, etc., as I can see no way of accessing these settings via the unit itself.

Needless to say, in the course of my review I didn’t need to do a whole lot of that. I connected my pair of Paradigm Studio 100 v.5 towers using a pair of Elac Sensible speaker cables, ran a Monoprice USB cable from my Maingear Vybe media and gaming PC to the USB input on the back of the amp, connected a second USB cable to my iFi Audio Zen One Signature DAC and ran its analog outputs to one of the G700M2’s line ins, ran LAPC, and got to listening.

Technics

Normally, with any amp that has pre outs or a dedicated subwoofer output, I’ll also connect an SVS PB-1000 Pro sub and a pair of RSL CG3 bookshelf speakers just to see how the amp benefits from a 2.1-channel setup, but since the Technics has no bass management (and to be frank, I’m honestly not even sure it could, given the JENO architecture), I didn’t really see much benefit in doing so in this case. So after a few days of casual background listening, I settled in for some critical evaluation without tinkering with different setups.

How does the Technics SU-G700M2 perform?

To be frank, given that Technics’ own specifications for the SU-G700M2 reveal total harmonic distortion figures that are sure to raise eyebrows ’round these parts (half a percent at max rated power), and given that it relies heavily on noise-shaping, I was on the hunt right out of the gate for audible noise and distortion.

There are a number of wonderful test tracks that reveal such flaws—Tracy Chapman’s “Fast Car” is legendary for its ability to illuminate certain types of distortion—but another of my favorites is Andrew Bird’s Echolocations: River (16-bit/44.1kHz FLAC, Wegawam Music Co. / Qobuz). Bird recorded the album while standing in the Los Angeles River under the Glendale-Hyperion Bridge. It is (was?) intended as the second of five Echolocations projects recorded in different environments, and it’s peak Bird if you’re more into his fiddle playing and looping than you are his whistling and vocals.

The album’s third track, “Lazuli Bunting,” starts off with the sounds of water burbling and rippling around his feet, as well as a sort of background pink noise that might be wind or distant traffic or some combination thereof. Bird also sets the tempo for the track by clapping his hands semi-rhythmically, which, given the location of the field recording, results in a fantastic organic echo and reverberation.

Technics

Any one of these elements in isolation would be a good indicator of audible distortion, but combine them and you can tell a competent amp from a non-competent one in just a few seconds. Any appreciable audible noise or distortion, and the rippling water in particular can take on a harsh, unnatural quality. The background drone can sound swooshy and discolored. The clapping and subsequent echoes can take on a brittle quality in their attack and a grainy quality in their decay.

I didn’t catch even the faintest whiff of any such colorations via the SU-G700M2. Its delivery of the track was spot-on in every respect. This isn’t a mix that lives or dies by highly specific imaging, mind you. It is quite diffuse, and the echoey hand-percussion in particular sort of comes from everywhere at once. But—and this is a big but—the soundstage is huge, both wide and deep, and the Technics excelled at the delivery thereof.

Looking for something that would give me a better sense of the amp’s imaging capabilities, I turned my attention to Santana’s first eponymous record (24/96 FLAC, Columbia-Legacy / Qobuz) and let rip the first track, “Waiting.”

From the first note, each percussive hit hung in the air like Eärendil’s Silmaril. For me, it was one of those magical hi-fi moments where I felt as if I could close my eyes, reach out in front of me, and pluck the sound of a conga out of the air between my thumb and index finger. I also simply adored the way the amp handled the timbres and textures of Gregg Rolie’s Hammond organ, especially the ascending chaos that starts at around 1:25.

More so than anything else, though, what I loved was the Technics’ handling of the album’s dynamics, its transients, the attack of every timbale hit, and, with songs like “Jingo,” the snarling bite of Santana’s TV Yellow Les Paul Special. Interestingly, though, when I got to “Soul Sacrifice,” my attention was drawn to some excessive distortion—perhaps you could even describe it as clipping—in Rolie’s organ at around the 4:35 mark.

Technics

If I’d ever noticed it before, it wasn’t significant enough to stick around in my memory, so I switched over to my near-field desktop system (SVS Prime Wireless speakers and a PB-1000 sub) for a closer listen. The same distortion was indeed present, though not quite as attention-grabbing. I had to switch over to my Schiit headphone amp and a pair of custom UE IEMs to hear the same level of distortion in the same stream of the same recording.

To me that says that the Technics is incredibly revealing. Perhaps more so than some people are comfortable with. But I’m a warts-and-all kind of guy, so I’m here for it. Yes, the errant clipping seemingly baked into “Soul Sacrifice” may rise to the surface more than it does with other integrated amps. On the other hand, super-fine details in other recordings—like the scraping of Joanna Newsom’s teeth across her lips in “Sawdust and Diamonds” from the album Ys (16/44.1 FLAC, Drag City Records / Qobuz)—were rendered with the sort of tactile palpability I don’t think I’ve heard since I played the song through Marantz’s PM-KI Ruby integrated amplifier ($3999).

For what it’s worth, I also plugged my Audeze LCD-2 headphones into the SU-G700M2’s headphone output and gave “Sawdust and Diamonds” a spin, as well as some of the aforementioned Santana tracks. Its performance was fine, and it didn’t have a bit of trouble driving these or any of my cans. But no matter which headphones or earphones I connected, I felt it lacked something in terms of that nth-degree of detail, clarity, and attack I got from the speaker-level connections. Comparing it with other headphone amps built into similarly priced integrated amps, I’d say it’s about par for the course.

Technics

I was wrapping up my critical listening when it occurred to me that I hadn’t really done much tinkering with the G700M2’s LAPC functionality to get a sense of how much audible difference it makes. With the Joanna Newsom track playing, I turned LAPC off and on again several times (each transition accompanied by a little less than a second of silence).

I kinda thought maybe I could hear a slight difference with regard to the clarity and balance of the very lowest notes on Newsom’s harp, but I also doubted my own observations.

I eventually stumbled on a track that, I think, showed the effects of LAPC quite unmistakably: Hans Zimmer’s “Dream of Arrakis” from Dune: Original Motion Picture Soundtrack (24/48 FLAC, WaterTower Music / Qobuz). At normal listening levels, it seemed to me that with the feature turned on, the bass was more robust, better balanced, more on even footing with the rest of the mix. As I turned the volume knob up, this impression only grew stronger. At listening levels approaching my tolerance, with LAPC off, I could feel my Paradigm towers thinning out ever so slightly. With it on, each weird, guttural, alien percussive attack seemed proportionally more correct.

So my best guess here is that, with three-way towers like my Paradigms, the biggest audible benefit of LAPC is in terms of keeping the overall tonal balance consistent even in the presence of deep bass, and especially at louder listening levels. I can’t say I heard any differences in terms of phase, although to be honest I’m not entirely sure what I should be listening for there. Still, the improvements in tonal balance—again, with bass-heavy music at louder listening levels—are enough for me to say there seems to be some genuine benefit to this technology.

What worthy competitors should you also consider auditioning?

If you’re shopping around for an integrated amp in this price range, right now I think there are two other options you should seriously consider, and I’m frankly happy I’m not currently in a position to choose between the three.

The first is NAD’s C 399 BluOS-D HybridDigital DAC-amplifier ($2549 once you add the MDC2 BluOS-D module). Comparing the NAD and the Technics is a bit of an apples-and-kumquats scenario, but they’re roughly on even footing in terms of physical I/O. The NAD has an HDMI input, but its phono stage only supports MM cartridges. It has dual sub outs and, with the addition of the MDC2 BluOS-D, customizable bass management. It also has built-in BluOS streaming and Dirac Live room correction.

But the C 399 isn’t going to win any beauty contests, and it lacks the Technics’ hypnotic VU meters, which genuinely add to the listening experience for me. To get those in the same brand, you’d have to upgrade to the NAD Masters Series M10 V2 ($2999), and they’re virtual at that.

There’s also the Marantz Model 40n network integrated amplifier-DAC ($2499), which lacks room correction, and has only MM phono support, but is built like Fort Knox . . . if Fort Knox had been designed by Frank Gehry. The Model 40n relies on HEOS for streaming and has an HDMI input, but only has one each of optical and coaxial digital inputs. It has pretty robust bass management, with your choice of 40, 60, 80, 100, or 120Hz crossover points.

Which is right for you, I obviously cannot say. But if I could combine all three, Voltron-style, into a single product with the looks of the Technics, the build quality of the Marantz, and the room-correction capabilities and streaming ecosystem of the NAD, that would be my ideal integrated amp. Despite the radically different amplifier technologies employed in each, they all sound absolutely fantastic, so my heart goes out to you if you’re picking between them.

TL; DR: Is the Technics SU-G700M2 worth the money?

If what you’re chasing is an incredibly revealing amp that looks like nearly nothing else (unless you’re willing and able to drop $9500 on that positively drool-worthy SU-R1000), the whippersnapper of Technics’ integrated amp lineup delivers. Full stop.

The only nits I have to pick are with the somewhat light and insubstantial-feeling volume knob (I’m a snob in this department, admittedly), the merely very-good headphone amp, and the fact that Technics expects people to read the instruction manual to understand what LAPC is and how to run it. And mind you, if you’re driving big three-way towers, I think you should run it, since I heard some audible improvements.

Technics

I have to admit, though, I’m super curious to see the results of our bench testing when Diego Estan gets his paws on this beauty. The SU-G700M2 is doing some very interesting things with noise-shaping, if I understand the white paper as well as I think I do. And while I can attest to the amp’s subjective performance chops with my speakers in my room, there’s always the chance that there’s some corner-case scenario I might not be able to reveal in my listening.

Even if Diego came back and revealed that this thing measured like a half-baked potato, though, I’m not sure that would diminish my love for it. And if it seems like I’m being picky with any of the above criticism, that’s probably why. I’m constantly concerned about confirmation bias, and the more emotional engagement I have with a product, the more likely I am to look at it skeptically, to doubt my conclusions, to fear that I’m missing or overlooking something. The SU-G700M2 triggers that feeling in me. Hard. And that’s probably the highest praise I could give it.

. . . Dennis Burger
dennisb@soundstagenetwork.com

Associated Equipment

  • Speakers: Paradigm Studio 100 v.5.
  • Speaker-level connections: ELAC Sensible speaker cables.
  • Sources: Maingear Vybe PC, iFi Audio Zen One Signature DAC.
  • Headphones: Audeze LCD-2, HiFiMan HE-500.
  • Power protection: SurgeX XR115 power conditioner.

Technics Grand Class SU-G700M2 Integrated Amplifier
Price: $2699.
Warranty: Three years, parts and labor.

Panasonic Corporation of North America
Two Riverfront Plaza
Newark, NJ 07102-5490
Phone: (201) 348-7000

Website: www.technics.com