AXPONA 2025: Electronics

The most eagerly anticipated new product in my category, electronics, was undoubtedly the Soulution 717 power amplifier. Not merely an update of its existing flagship, the 717 is an entirely new animal. In stereo mode, the 717 outputs 150Wpc into 8 ohms, a figure that doubles as the impedance is halved, all the way to 600Wpc into 2 ohms. In bridged mode, the 717 can output 600Wpc into 8 ohms. It features four 600VA switch-mode power-supply modules with very short signal paths from the power supplies to the circuits they supply and the loudspeaker binding posts. The audio circuitry is all new. I heard the prototype 717 briefly at the Soulution factory after last year’s Munich show and was taken aback by how much more lifelike it sounded than the company’s already fabulous 701. The price is $119,995, a figure that doubles if you run a pair of 717 in monoblock mode.

PS Audio showed four products in the new Paul McGowan Signature Series. The PGM Signature components feature identical and gorgeous casework made possible by building the same chassis-within-a chassis structure for all four products to realize economy-of-scale manufacturing. The PGM Signature series features 1½**-thick front panels and a very cool round illuminated touchscreen display. The linestage preamp, phonostage, DAC, and CD/SACD transport share the same retail price of $8495. The PMG Signature PureStream DAC replaces the company’s DirectStream DAC. Since I’m covering electronics, I’ll talk only about the linestage and phonostage. The linestage features all film caps, with no electrolytics, even in the power supply. It features a 1MHz bandwidth, custom stepped-attenuator volume control, and an astonishing –150dB noise floor. The phonostage offers a conventional voltage input as well as a transimpedance input (also called a current input) for cartridges with a very low internal impedance. The fully complementary, all-discrete circuit uses zero global feedback, offers balanced and unbalanced inputs, and variable cartridge loading by remote control. It looks like a lot of phonostage for the price. If these products sound as good as they look on the outside and inside the chassis, PS Audio has a winner. Shipments begin in June.

The venerable Audio Research Corporation introduced no fewer than six new models that are priced within reach of more music lovers. The three tube and three solid-state products start at $7450 and top out at $12,950. First up is the LS-2 tube linestage built around two 6H30 tubes. It features four single-ended inputs, two balanced inputs, and can accept an optional mm/mc phono card and an optional DAC card. A large touchscreen display dominates the front panel. Price: $8450 without options, rising to $9950 when fully loaded.

The LS-3 preamplifier is essentially a solid-state version of the LS-2, with all the same features, chassis, front-panel display, user interface, and remote control. The LS-3 costs $1000 less than its tubed sibling.

Next up is Audio Research’s S-100, a 100Wpc stereo Class AB power amplifier. It features a dual-mono architecture including separate transformers for each channel. The circuit is a balanced differential design and includes XLR and RCA inputs. Price: $9450. For those wanting more power, ARC offers the S-200 with 200Wpc along with the same circuitry and feature set as the S-100. The big brother, however, has a pair of large power-output meters on the front panel. Price: $9450.

Next up is the D-80 is an 80Wpc vacuum tube amplifier built around a pair of KT-150s per channel operated in pentode. The amplifier is a balanced differential design and offers only balanced XLR inputs. It is built on ARC’s REF80S platform. Price: $12,950.

Finally, we have the I/70 tubed integrated amplifier. Unlike the five all-new products just described, the I/70 is essentially an upgraded version of the company’s I/50 integrated amp with more output power (70Wpc) and built with the same platform and tube complement (two 6550s per channel). The higher output power is realized by replacing the transformer with the transformer from the company’s REF75 amplifier. The upgraded transformer reportedly also allows better control over challenging speaker loads along with wider dynamics and higher resolution. The input and driver stage are all tube, as is the headphone amplifier. The I/70 employs ARC’s auto-bias circuit. The I/70 can be loaded with optional phono and DAC boards, and it offers additional expansion capabilities with its preamplifier output jacks and subwoofer output. Price $9950 and $11,450 fully loaded.

Pass Labs showed its new flagship preamplifier, the XS Pre 2, a three-box affair with separate chassis for control electronics and left and right audio-channel electronics. The new model is an improvement and update of the XS preamp that has been Pass Labs’ flagship for 12 years. The new three-box design results in quieter circuitry. The power supply is now dual mono with three double-shielded transformers along with more filter capacitance and additional pre-regulation stages. The output stage has more Class A bias and lower output impedance. The circuit boards feature a new ceramic-based material with gold traces. The circuitry is based on Toshiba FETs in the input stage and MOSFETs in the output stage. Wayne Colburn, who designs all the phonostages and linestages for Pass Labs, says it is the best design he’s created in his more than 35 years of amplifier design. Price: $55k in silver, $56k in black.

CH Precision, known for their ultra-high-end electronics, recently acquired Wattson Audio, a Swiss high-end manufacturer. CH Precision began collaborating on designs with Wattson Audio and brought Wattson’s manufacturing in-house to offer a line of electronics that bring some of the CH Precision DNA to more affordable products. The first offering from this collaboration is the Madison, a compact Class AB power amplifier delivering 50Wpc. The Madison is designed and built entirely in Switzerland in the same factory as CH Precision’s electronics and even shares some design techniques and parts with CH products. In fact, the Madison’s single pair of output transistors are identical to those in CH’s $200k M10 flagship amplifier. The Madison was demonstrated with Wattson’s Madison Streamer where the pair sounded fabulous driving the Magico S3 2024—not an easy load, incidentally. The sound had a wonderful purity and expressiveness, transparent soundstage, and excellent dynamics. It was hard to believe that I was listening to just 50Wpc. The sound was like that of the CH M10 but scaled down in power. Price: $6495. Watch for our upcoming review.

Auspicious Debuts

Theory and Application elektroakustik (T+A) from Germany showed two new integrated amplifiers that are each a single-box distillation of their excellent half-chassis R200 series. A third model in the line will be introduced in Munich. The model I saw is called the Symphonia Streaming Integrated Amplifier, and it is packed with functionality and connectivity. It features T+A’s new streaming engine that supports Roon, Qobuz, Tidal, Deezer, etc. Other proprietary T+A technology includes a dual-differential DAC architecture along with the company’s DSD decoding circuitry. The Symphonia also offers FM radio, DAB, Internet Radio, bi-directional Blueooth, DLNA/UPnP, and HDMI with ARC. If that’s not enough, a phonostage that will accommodate mm or high-output moving-coil cartridges is included, along with a subwoofer output jack. The Class-D power amplifier section, based on the superb Eigentakt module, delivers 125Wpc into 8 ohms and 250Wpc into 4 ohms. Price: $9995.

Valve Amplification Company (VAC) had a great show, producing terrific sound with its new Statement 450iQ power amplifiers. These are an evolution of the company’s flagship product, now with a bigger power supply, improved transformers, and a new driver stage, among other advancements. The KT-88-based amp produces 230Wpc into 8 ohms in stereo mode, and 460W when used as a monoblock. Driving Acora’s top VRC speaker and sourced with a SAT turntable and tonearm with a Lyra Atlas cartridge, the Statement 450iQ was magical. See Jonathan Valin’s show report for a detailed description of this room.

At the other end of the scale, VAC introduced its most affordable components yet, the Essence Linestage and Essence 90 iQ monoblock amplifiers. The Essence 90 iQ features a pair of Gold Lion KT-88 power tubes along with VAC’s patented iQ Continuous Automatic Bias System that keeps the output tubes perfectly and automatically biased. Although a compact design, the Essence 90 iQ features a 14-pound transformer along with a direct-coupled input and driver stage built around two 6SN7GTB twin triodes operating in Class A. A rear-panel switch configures the amplifier to accept single-ended or balanced inputs. Output power is rated at 90W continuous. Price: $9900.

Vandersteen showed the full production version of its L5-ACC linestage (“ACC” stands for Audio Control Center). It may seem odd for a loudspeaker manufacturer to introduce its first preamp after nearly 50 years of making speakers, but the L5-ACC is the linestage that Richard Vandersteen always wanted for his own system but that wasn’t commercially available. He figured that other folks might want the L5-ACC’s unique features as well. Those features include bass and treble controls that are implemented in a way that doesn’t degrade sound quality. The amount of adjustment is limited and sensible—just enough to nudge the system in the right direction. The preamp also offers tone-adjusted presets. Next is a mono-blend circuit to reduce the “ping-pong” mixes prevalent in the early days of stereo recording—drums 100% in the right channel and the lead instrument 100% in the left channel, for example The mono-blend circuit reduces that exaggerated stereo effect and is selectable on the L5-ACC remote control in four steps including full mono. Finally, the L5-ACC incorporates a matrix that takes out-of-phase information from each channel, inverts it, and mixes it back in on the theory that this out-of-phase information restores the natural ambience encoded in the recordings. Price: $15k.

I spent some time getting a technical briefing on the new Atoll IN400 Evolution integrated amplifier. This is an overhaul of the IN400 SE that Neil Gader reviewed so enthusiastically in 2017. This new model brings circuit improvements along with a thoroughly modern feature set. New features include two balanced inputs, DSD decoding, and Bluetooth connectivity. In addition, the unit accepts an optional digital decoding board. In speaking with the company’s owner and the lead engineer, I was impressed by the product’s focus on sound quality. The circuit is all discrete (no op-amps), has separate transformers for the audio and control circuitry, is a low-feedback design, and its output stage has eight MOSFETs per channel. Power output is 160Wpc into 8 ohms, and 300Wpc into 4 ohms. This ability to nearly double the output power as the impedance is halved indicates a robust power supply and power-output stage. The $7500 IN400 Evolution was part of an excellent sounding system that included the company’s CD400 Evolution CD player and ST300 Signature streamer/DAC/preamp driving Dynaudio Contour Black Edition loudspeakers.

Germany’s AVM showed an interesting AC power conditioner, called the PL 5.3, that allows you to see and hear the noise on the AC line—noise that the PL 5.3 removes. The company offers two conditioners, the six-outlet PL3.3 at $4900 and the 12-outlet PL5.3 at $6900, with identical features and performance.

In Other News

I heard an absolutely gorgeous sound in the room of dealer/distributor Gestalt Audio that featured Wolf von Langa Ultima loudspeakers with a field-coil driver and AMT tweeter. The amplification was a pair of SW1X MPA V monoblocks with a whopping 6W of output power. That was more than enough to power the Ultimas. The SW1X amplifiers are Class A, tube rectified designs with a directly heated triode output tube which varies with model. The amplifiers all feature interstage transformer coupling. Price: $35,895 per pair. The SW1X Pre III LPX Classic preamplifier ($29,995) fronted the system. SW1X is a British company that makes a wide range of extremely esoteric electronics.

I heard more excellent tube sound in the Engström room (Rhythm Distribution) featuring Engström Eric Encore monoblocks ($180,000 per pair). Driving Marten Parker Trio Diamond loudspeakers, the 70W Class A Eric Encore had a beautiful tonality and spatial dimensionality. The system also included the Engström Monica MK3 Preamplifier ($70,000) and Engström M-Phono MK2 Phono Preamplifier ($35,000).

The French company Devialet that made a splash many years ago with its slim line of amplifiers employing a unique Class-A/Class-D hybrid output stage, showed a new integrated amplifier due for release later this year. Called Astra, the integrated amplifier is packed with features and connectivity including AirPlay, Google Cast Built-in, Roon Ready, Spotify Connect, UPnP and Tidal Connect. It also features Devialet’s Speaker Active Matching (SAM) circuitry that adjusts the amplifier’s output stage characteristics to best drive a specific speaker’s impedance curve and sensitivity. Robert E. Greene has favorably evaluated SAM in a previous issue. The amplifier’s initial setup is through an on-line configurator, allowing you to configure the inputs for your particular system, set phono gain and loading, and choose your speaker from more than 12,000 speakers in Devialet’s database to engage Speaker Active Matching. Available in silver or gold, the Astra will sell for $20,000 when it begins shipping this summer.

Boulder Amplifiers demonstrated its newly introduced 1151 monoblock amplifier and 1162 stereo amplifier. The 1151 is rated at 350W of peak power (250W continuous), and features Boulder’s Class-A Smart Current Biasing Circuit. In typical Boulder fashion, the output stage is massive, with 40 output transistors fed from 12 large supply capacitors. The 1162 is a stereo amplifier that outputs 300Wpc into 8 ohms. Prices are $23,500 each for the 1151 and $45,000 for the stereo 1162.

RH’s Best of Show

Best Sound (cost no object): Stenheim Ultime 2 SX driven by VTL amplification with Nordost cabling.

Best Sound (for the money): PS Audio Aspen FR-5 loudspeaker ($3000 per pair). This little standmount played way above its size and price, filling a large room with a big soundstage and deep bass.

Most Significant Introduction: Soulution 717 power amplifier. Soulution’s 701 was already world class, and this new model promises to establish a new benchmark in amplifier performance.

Most Coveted Product: The Dan D’Agostino Master Audio Systems Relentless preamplifier is a work of sonic, industrial, and visual art.

Most Significant Trend: The incredible price escalation at the very top of the high end, along with a proliferation of great-sounding affordable gear at the entry level.