Recommended Components

Integrated Amplifiers & Receivers:

A:

ampsandsound Red October SE: $14,000
ampsandsound Red October XL SE: $18,000
See Headphones and Headphone Accessories. (Vol.47 No.11 WWW)

Anthem STR Integrated: $4999.99 $$$ ★
Anthem’s solid state STR integrated amp offers 200Wpc (into 8 ohms) of class-AB power, along with seven analog inputs—one balanced, four single-ended, and two phono (one MM, one MC). It also offers a 32/192 D/A processor with six digital inputs—four S/PDIF (two RCA, two TOSLINK), one AES3 (XLR), and one USB. A subwoofer output is provided, but, curiously, there’s no headphone output. Of interest to users with problematic listening rooms is the STR’s built-in Anthem Room Correction (ARC) processor: using the supplied microphone, ARC can be set up using a PC that’s been configured with the appropriate (downloadable) software and connected to the Anthem’s miniUSB or Ethernet jack. (The latter has no other function: the STR is not Wi-Fi capable.) Even before setting up and trying ARC, Tom Norton enjoyed the Anthem STR for sounding, with one recording in particular, “punchy and likely true to the source, with excellent detail and an open midrange.” With ARC engaged, Thomas J. Norton heard differences that “ranged from subtle to striking … and were only rarely inconsequential.” Benefits included a “cleaned up” double-bass sound on one CD, greater upper-bass precision in the sounds of massed voices on another. His conclusion: “a watershed product worth serious consideration.” Writing of his experiences in measuring the Anthem STR, John Atkinson called it “a well-engineered amplifier offering high powers and respectable measured performance.” (Vol.41 No.7 WWW)

Audia Flight FLS10: $18,997
Though it was introduced in 2017, this Italian integrated was recommended to Rogier van Bakel for driving a pair of large panel speakers that he will be reviewing in a future issue. Not only did it do well with those speakers—“taut, deep bass, complete with slam and authority. From a pair of panel speakers, no less!”—it also worked well with van Bakel’s reference Focal speakers and the Estelon X Diamond MkIIs (see Loudspeakers). Although he had some ergonomic issues with the front panel’s controls and display, van Bakel felt that the FLS10 “animates even speakers with difficult loads. Above all, it doesn’t just play music—it unlocks it. From heavy metal and EDM to jazz and pop and classical fare, the amplifier’s speed tended to stay one step ahead of my high expectations, and the reproduction never felt frantic or mechanical.” Image density was of the reach-out-and-touch-it kind. While van Bakel found the Audia Flight’s midbass to be slightly mellow, it didn’t sound warm in a bloated, nostalgic way—its “sensuous shimmer” kept pulling him in. Paul Miller reported from his test lab that the FLS10 exceeds its 200W/8 ohm rating by delivering 245Wpc into 8 ohms, as well as delivering 440Wpc into 4 ohms. Distortion at moderate powers was very low, but Paul Miller did note that there was some low-level hum in the amplifier’s output, possibly due to the huge power supply being in close proximity to the audio stages. (Vol.48 No.2 WWW)

Audio Note Meishu Phono 300B Tonmeister (Standard version): $17,850
This class-A, zero negative feedback, single-ended-triode integrated’s power supply uses a 5U4G tube rectifier, with each channel’s line input using a Psvane Hifi Series 12AU7/ECC82 and a NOS Philips ECG 5687WB to drive an interstage transformer. Each phono input channel uses a Psvane Hifi Series 12AX7/ECC83 and either a Sovtek/Electro Harmonix 6922 or a Russian ECC88. A single Psvane Standard Hifi Series 300B tube provides the output power, specified as 8Wpc into 8 or 4 ohms from the appropriate transformer tap. Ken Micallef found this plenty enough power for his high-sensitivity DeVore Fidelity O/96 speakers. Playing LPs, he wrote that the Audio Note’s performance “was whole cloth, transparent, with superquiet, black backgrounds. It was texturally and tonally beautiful. Mesmerizing, providing new insight into familiar recordings, resolving previously unheard details.” “Words fail to express the satisfaction I derived listening to music through this expensive Audio Note integrated amplifier,” Micallef concluded. In the test lab, John Atkinson concluded that the Meishu Phono Tonmeister’s measured performance was what he would expect from an amplifier with a single-ended output stage that uses a single 300B tube for each channel. It featured a high source impedance and high levels of predominantly second-harmonic distortion, even at low powers. While noting the measured performance characteristic of its type, Editor Jim Austin awards Class A for exceptional musicality. (Vol.46 No.2 WWW)

Aurorasound HFSA-01: $4290
This versatile amplifier from Japan uses high-quality solid state circuitry for its preamp and phono stage circuits and a pair of push-pull EL84 tubes for each channel’s output stage. The MM phono stage offers the universal RIAA equalization curve but, unusually, the treble and bass controls can be overlaid with a template that allows them to be set to give other EQ options. Using the Aurorasound to drive high-sensitivity speakers from Ampeggio and Voxativ, Ken Micallef commented that it “played well with all kinds of music, its forward-motion pacing, exacting clarity, and exceptional coherency making it a fine dance partner regardless of the tune.” He was impressed by the phono stage, finding that the HFSA-01 played music with liveliness, buoyancy, and rhythmic drive. “This smallish amplifier produced sound that was full-bodied, dynamic, and large in scale,” he noted. Summing up, Micallef wrote that “the HFSA-01’s clearheaded, precise character makes it easy to enjoy. It is very expressive. It delivers the heart and heat of music with a dancelike, easy on its feet, whirlwind intensity; … the Aurorasound absolutely zips through music with the kind of speed and dynamics I associate with well-made solid state amps but with the tonal flavoring of the best tube amps. [It] swings, boogies, and sizzles, at a price commoners and oligarchs can love.” The HFSA-01 is specified as being able to output 14Wpc into 8 ohms; John Atkinson found that the amplifier would only deliver this power from the 8 ohm tap into 8 ohms and the 4 ohm tap into 4 ohms at close to 10% THD+N. Fortunately, distortion was predominantly the subjectively benign second and third harmonics. Distortion at low powers was very low, provided that the load impedance was equal to or greater than the nominal output transformer tap impedance. Atkinson concluded that the best performance was obtained from the 4 ohm output tap, the 8 ohm tap not being able to maintain its linearity into loads below 8 ohms. The phono input offers low noise and high overload margins. (Vol.48 No.3 WWW)

AVM Evolution AS 5.3: $12,999
The AS 5.3 uses a pair of ECC83/12AX7 tubes in its preamp stage and a Pascal-based class-D module in the output stage, the latter capable of 180Wpc into 8 ohms or 350Wpc into 4 ohms. There are four single-ended analog input pairs (including one phono, configurable for either MM or MC, with selectable gain and adjustable loading, capacitive for the former, resistive for the latter); a single pair of XLR inputs; a fixed line-level output on RCA; a variable preamp output on both RCA and XLR; and a headphone output. Via the Roon Ready streaming inputs, the DAC handles DSD up to DSD256 and PCM up to 32/384. Via the digital inputs, the AS 5.3 is capable of converting music data up to 24/96 (TOSLINK) and 24/192 (coaxial S/PDIF). Although there are front-panel controls, Ken Micallef preferred using the versatile AVM RC X app to choose the input, adjust the phono input settings, and set the volume. He noted that the phono stage earned its stripes for its exceptional layering, forensic resolution, and an uncanny quiet background. He also found that the AS 5.3’s streaming identity was tightly woven and superbly layered: “When matched with an appropriate speaker, bass possessed warmth and weight, forceful and direct.” He was impressed by the fact that the AS 5.3’s sonic character didn’t change much between phono and streaming—“just a sliver less bass weight and harmonic richness with streaming.” “The AVM Evolution AS 5.3 Streaming Amplifier packs an exceptional phono stage,” concluded Micallef, adding that “it has plenty of power, a well-designed, usable app, and it works as well with analog sources as with digital. It all fits into a relatively lightweight package.” On John Atkinson’s test bench, the AVM amplifier exceeded its specified powers, clipping at 245Wpc into 8 ohms and at 310Wpc into 4 ohms. While it offered somewhat compromised channel separation and S/N ratios with the volume control set to the maximum, found Atkinson, the AVM AS 5.3’s measured performance with its line-level, phono, and digital inputs at lower volume settings was very good. (Vol.49 No.6 WWW)

Balanced Audio Technology VK-80i: $12,000
The fully balanced, hot-running, push-pull VK-80i produces 55 triode watts per channel from two pairs of 6C33C-B output tubes autobiased into class-AB while relying on a very restrained 3dB of global negative feedback. Four 6SN7 tubes perform line-level input duties. Alex Halberstadt was struck by the vigor, scale, and dimensionality the BAT brought to an LP by Angolan singer Waldemar Bastos. “The sometimes startling dynamics of Bastos’s singing were conveyed with beauty and bracing force and without a hint of strain, breakup, or distortion,” he wrote, adding that the BAT’s knack for transparency was aided by its very low noisefloor. Halberstadt’s conclusion? “It will not produce the most ravishing sound you can hear—clearly being the work of an engineer rather than a poet—but it will extract plenty of meaning and emotion from your favorite recordings.” (Vol.47 No.3 WWW)

Burmester 232: $25,000; $40,000 as reviewed
MC phono module adds $5000; Roon Ready DAC/streamer module adds $10,000; custom finishes add $3000. There are two balanced analog inputs, a plethora of digital inputs with the optional digital module—two USB 2.0, Type A, one USB-C, microSD (SD1), HDMI ARC, S/PDIF, TOSLINK, and AES3—and as well as the speaker outputs, there are balanced preamp outputs (one fixed, one variable), a 6.3mm headphone jack, and S/PDIF and TOSLINK digital outputs. The 232 is rated at 95Wpc into 8 ohms and 155Wpc into 4 ohms—John Atkinson measured clipping powers of 95Wpc and 150Wpc, respectively. Jason Victor Serinus initially auditioned the analog inputs, commenting that timbres sounded extremely natural, with ideal warmth in the midrange. He never felt detail was lost or smudged. Nor was there any lack of bass. Using the digital module, he wrote that the colors weren’t as saturated and fleshed out as through his 33-times-as-expensive Innuos/dCS reference combo, “but the essential qualities of the music, and the feelings it arouses in me, are all there.” Serinus also noted that the best sound he’d heard from the 232’s DAC module was with a file played directly from a USB stick rather than streamed. “Highly recommended,” he concluded. Atkinson found that the Burmester 232’s measured performance with the analog inputs was superb, with extremely low distortion and noise. Other than the excessive gain, the DAC/streamer module’s measurements were very good, he noted. (Vol.49 No.3 WWW)

CH Precision I1 Universal Integrated Amplifier: from $38,000; As reviewed $48,500 ★
CH Precision’s decidedly modular I1 Universal integrated amp/D/A processor can be had with a variety of extra-cost options, including a USB digital-input board, an Ethernet-input streaming board, an MC phono-input board (with more EQ curves than just RIAA), and a clock-synchronization board that permits the use of an outboard digital clock. In its base form ($38,000), the I1 provides one pair each of balanced (XLR) and unbalanced (RCA) analog inputs, plus an S/PDIF digital-input board and two balanced (XLR) stereo outputs. Echoing the future-proof design of the amp itself is the I1’s D/A processor, which is coded into a field-programmable gate array (FPGA); this upsamples 16/44.1 PCM and its multiples to 24/352, and 16/48 PCM to 24/384. The I1 handles up to DSD256 and converts all DSD data to 24/352.8 before playback. Its class-AB output section can provide up to 100Wpc into 8 ohms. Notwithstanding some setup complexities, Jason Victor Serinus was able to get from the I1 “some mighty impressive sound,” and to the extent it fell short of his own (costlier) reference gear, those were “sins of omission rather than of commission.” Serinus found the CH Precision’s sound to be “clean, strong, and direct,” yet it did not “filter out those intangibles that allow the music to elicit a powerfully emotional response.” His verdict: “one of the most complete, most neutral sounding, most carefully conceived components I’ve reviewed.” Writing from his test bench, John Atkinson praised the I1’s “excellent measured performance,” and in his own auditioning of a sample with updated, Roon Ready firmware, found that 40% overall negative feedback gave the optimal balance between low-frequency definition and the unfatiguing presentation of high-frequency detail. (Serinus preferred 0% feedback.) Atkinson was impressed by the DAC performance, writing that imaging was precise, the soundstage deep when appropriate, and the midrange uncolored. “Low-level recorded detail was present in abundance but without the feeling that it was being unnaturally emphasized,” he concluded. (Vol.42 No.2, Vol.46 No.8 WWW)

Devialet Astra: $20,000
This slim class-D streaming amplifier is specified as offering 150Wpc into 8 ohms and 300Wpc into 4 ohms; John Atkinson measured clipping powers of 165Wpc into 8 ohms and 325Wpc into 4 ohms. As well as line and MC/MM phono inputs, the Astra features Ethernet, USB 2.0, and coaxial and optical S/PDIF digital inputs. Supported formats are up to 24/384 PCM via USB; up to 24/192 PCM via Ethernet and coaxial; up to 24/96 PCM via optical; DSD128 via USB; and DSD64 via coaxial and Ethernet. Wireless streaming is supported over Google Cast, Apple AirPlay2, Bluetooth 5.3, UPnP, Spotify Connect, Tidal Connect, Audirvāna, and Roon. The Astra can be controlled with both the Devialet app and the versatile remote control. A configurator optimizes the phono input performance for a large database of supported cartridges. An impressively wide range of EQ curves, loading, and channel-balance settings are available. (The electrical settings are applied in the analog domain; the chosen EQ curve is applied after conversion to digital.) Devialet’s SAM (Speaker Active Matching) function uses DSP to optimize the operation of 1200 loudspeakers, including Ola Björling’s Focal Scala Utopias. There is also a fixed-frequency two-band EQ that’s adjustable from –12dB to 12dB in 1dB increments. Björling auditioned the Astra with a variety of phono cartridges and streaming services and was impressed by the Astra’s effortless bass extension and control, silky midrange liquidity, and a masterful coherency to the sound. He summed up his experience by writing “As a singular centerpiece to a digital system—just add speakers—the Astra’s sleek beauty matches its imperturbable sonics. Its adaptability across input and output configurations, SAM, equalizer, and subwoofer support makes it an unusually safe bet, but never boring or dull—no matter what future rooms and speakers it gets to perform with.” Atkinson found that the Astra offered superb measured performance with its line, phono, and digital inputs, with very low harmonic and intermodulation distortion, very low noise, and high resolution. (Vol.49 No.6 WWW)

Elekit TU-8900: from $2075 without tubes $$$
Herb Reichert was impressed by this relatively inexpensive, heavily parts-curated, made-in-Japan, tubed kit amplifier. (It can be purchased preassembled for a $375 premium. A clear top plate is included in this cost, and is a $35 kit option.) Lundahl amorphous-core output transformers are combined with 12BH7A small-signal tubes and 300B or 2A3 output tubes, both wired without cathode feedback but with 8dB of loop negative feedback. (This can be switched out.) Specified output power is 8Wpc with 300Bs, 3.5Wpc with 2A3s, both at 10% THD. The review sample was fitted with the Audio Note Silver upgrade ($960), which adds Audio Note 0.1µF silver-foil coupling capacitors, 46 tantalum signal path resistors, two Amtrans AMRG resistors, and four Takman carbon resistors. The Elekit’s four tube-set options begin at $365, for two Cossor/LinLai Delux 2A3s and two Sylvania 12BH7As, and top out at $1525 with a matched pair of Western Electric WE300Bs (with a 5-year warranty) and two US-manufactured Sylvania 12BH7As. After much experimentation using multiple speakers, Reichert decided that he preferred the TU-8900’s presentation without loop negative feedback: “Everything felt more impactful, more emotionally fleshed out. Every Elekit 300B virtue was enhanced, especially texture and transparency.” “This kit delivered the nuance, intensity, and dramatic transparency of big-name 300B amplifiers costing many times its price,” he wrote. Reichert was also impressed by the TU-8900’s headphone output. Driving low-impedance HiFiMan Audivina closed-backs, he found that the Elekit sounded authoritative, though he felt that it got a bit tense and dulled trying to drive HiFiMan’s less-sensitive Susvaras. (Vol.46 No.7 WWW)

Grandinote Shinai: $16,000
Echoing tube-amplifier topologies, the Italian, dual-mono, fully balanced Shinai features two single-ended, class-A, solid state output stages in a push-pull arrangement for each channel, with no loop negative feedback. “As long as I am Grandinote boss,” designer Massimiliano Magri told Robert Schryer, “feedback will be prohibited like sincerity in politics.” Schryer liked what he heard from this unique amplifier: “The Shinai made aural space microscopically tangible,” he wrote, adding that the amplifier has “a knack for detail retrieval” and “gave notes and musical lines enough space to stretch out and seamlessly transition into the next notes and musical lines.” This transparency was achieved without the presentation sounding clinical or etched: “The Shinai has the spirit of a revealer. It speaks the truth—not ruthlessly, but honestly.” In the test lab, the Shinai almost met its specified maximum power of 37Wpc into 8 ohms at 3% THD+N, though John Atkinson warned against using the Grandinote with speakers whose impedance dropped below 4 ohms. Atkinson summed up the measured performance by saying that it “is dominated by the designer’s decision not to use negative feedback. I would expect the Shinai’s sonic character therefore to be similar to that of a typical tube amplifier.” However, Schryer concluded that the Shinai “did some things better than my tube gear—definition, detail, space, scale, touch.” Two months after he submitted his review, Schryer was astonished to find that the Shinai’s sound exploded: “It blew open musically. As good as it was already, the sound went from here up to there, overnight.” An enigma, but lengthy listening sessions confirmed his impression. He concluded that the Shinai sounded “rich and bloomy but with a sense that you’re hearing the true, original thing and not a recording.” (Vol.43 No.11, Vol.44 No.4 WWW)

Gryphon Diablo 333: $27,800; optional DAC 3 Module: $8400 and PS 3 Phono Module: $6800
The “333” in this massive amplifier’s name refers to its stated output power of 333Wpc into 8 ohms. (Paul Miller found it could deliver close to 360Wpc into 8 ohms and 650Wpc into 4 ohms.) The output stage is biased to run >10W in class-A into 8 ohms. The review sample was fitted with the optional DAC and phono modules. The digital inputs—USB, AES3, TOSLINK, and coaxial S/PDIF—are fed to the new ESS Sabre ES9039PRO DAC, which provides a choice of seven reconstruction filters. There’s no wireless or Ethernet streaming capability, however. The MM/MC phono module offers multiple loading and gain options, but as it has balanced XLR input jacks, adapters will need to be used with most turntables. When Stephen Mejias auditioned the phono module, he commented that the visceral power of the Diablo 333 driving his Wilson speakers benefited electronic dance music. He wrote that while “grip,” “slam,” and “control” all applied to the Gryphon’s presentation, there was much subtle stuff going on as well. With a CD of Richard Strauss’s Symphonia Domestica, the massed string sections had a palpable sense of the ebb and flow around the musical phrases—“as you feel in live performance.” “The Diablo 333 can power anything, while producing amazing lifelike dynamics, the blackest blacks, and the brightest colors,” he concluded, adding that “the sheer amount of musical energy conveyed, and the detailed truth of that—you need to hear it for yourself.” Paul Miller summed up the measured performance of the digital module, which had “fabulously low jitter,” by writing that “as with the Diablo 333 itself, Gryphon has seemingly engineered the DAC3 to achieve a specific combination of technical and subjective qualities, and the results suggest it’s at the top of its game.” (Vol.48 No.1 WWW)

Leben CS-600X: $9995
With its wooden enclosure, the versatile CS-600X’s appearance is inspired by mid–20th century American integrated amplifiers from the likes of Fisher and H.H. Scott. It uses four New Sensor EL34 output tubes, and its maximum power is specified as 28Wpc. Driving Klipsch La Scala speakers from its 8 ohm tap, Alex Halberstadt found that the Leben sounded a bit bass-heavy and slow. Switching to the 6 ohm tap “tightened the bass, improved the speed, and otherwise dialed everything in,” he wrote, commenting about “the ample drive, grunt, and dynamic freedom—for me, the first and least things a good amp should accomplish.” The CS-600X can be fitted with tubes other than the EL34s. Subbing in Russian Gold Lion KT77 reissues lent the amp more grunt, color, scale, and body. But it was with Sophia Electric’s Coke-bottle-blue–glass KT88s that the amp began cooking with gas: Scale became obviously bigger, separation improved, bass tightened up, and close listening became easier and more fun. Halberstadt was also impressed by the CS-600X’s headphone output. Overall, the Leben is probably not for those whose chief passion is analyzing sound, “but it’s superb at allowing you to be carried away by the music on your favorite records.” (Vol.47 No.12 WWW)

Lejonklou Boazu 2.0: $6195
Rated at 40W into 8 ohms and 70W into 4 ohms, the Boazu drove Alex Halberstadt’s BLISS Jubilé speakers with effortlessness and beautifully articulated bass. The speakers sounded admirably neutral and reasonably resolute, he wrote, noting that while the Boazu couldn’t match the tonal contrasts, transparency, and deep color saturation of the very best tube amps … it offered the sweetest, most inviting sound he’d heard from solid state devices. “No, they don’t ‘sound like tubes,’ but neither do they truck in the opacity, hardness, and grayish tonality of some transistor-based components.” (Vol.49 No.4 WWW)

Linear Tube Audio Z10e: $6950 ★
Class A as a headphone amplifier and as a low-power integrated. See Headphones & Headphone Accessories. (Vol.43 No.5, Vol.44 No.2, Vol.45 Nos.1 & 3, Vol.48 No.7 WWW)

Luxman L-509Z: $14,495
Luxman’s new flagship solid state integrated has the same thick aluminum top plate and steel casework as the L-509X that Ken Micallef favorably reviewed in 2018 and, other than a Pentaconn headphone jack on its front panel, looks identical. However, it replaces the older amplifier’s op-amp chips with discrete circuitry and incorporates Luxman’s new LIFES feedback system, which is said to lower noise and distortion and reduce the unwanted effects of using negative feedback. There are balanced and single-ended line inputs and an MC/MM phono input. Specified power is 120Wpc into 8 ohms and 220Wpc into 4 ohms, which was confirmed by John Atkinson. The amplifier offers treble, midrange, and bass controls; these are bypassed in “Line Straight” mode, and Micallef found that this mode “made music sound cleaner, better focused, well organized, and orderly but perhaps a little rigid.” After a lengthy break-in, the L-509Z’s pure sonorities in the upper mids through the treble captured Micallef’s ears. “This is an amp of brilliant purity and fluid communication,” he wrote. “Its squeegee-clean top end allowed cymbals, guitars, pianos, and percussion to resonate and communicate direct to my gut.” He commented that the L-509Z had no obvious signature. “It was largely music and equipment agnostic,” he concluded. “Its message is clarity, balance, coherence, seamlessness, quietude, and a certain invisibility.” Atkinson added that “Overall, Luxman’s L-509Z offers excellent measured performance, especially its low-noise, low-distortion, overload-proof phono input.” (Vol.47 No.2 WWW)

Luxman L100: $11,995
See Ken Micallef’s review on p.145. (Vol.49 No.10)

MOON by Simaudio 371: $6500
The Roon-certified MOON 371 integrated amplifier offers Ethernet and Wi-Fi streaming. It can process up to 32/384 PCM and DSD256 from the major service providers: It incorporates Qobuz, Tidal, Spotify, etc., via their “Connect” apps or by integrating those services into the Simaudio MiND network music player app. As well as line-level inputs and S/PDIF, TOSLINK, and HDMI-ARC digital inputs, the 371 has an all-analog phono stage that supports both MM and MC cartridges. The class-AB output stage offers 100Wpc into 8 ohms or 200Wpc into 4 ohms. (John Atkinson measured clipping powers of 135Wpc into 8 ohms with both 1kHz and 20kHz signals and 265Wpc into 4 ohms.) Stephen Mejias’s first impression, playing a Mel Tormé LP with a Sumiko MM cartridge, was of a sound “that was almost tubelike, in a good way.” An aspect he immediately noticed playing both LPs and CDs was the level of soundstaging detail that the MOON 371 brought to the table: “Detail and textures were superb, no trace of grain or etch.” Mejias concluded that “the really delicious aspect of this French-Canadian prix fixe menu is the quality of the sound. Achieving low distortion figures, and a high damping factor, aids in creating an unusually black, low, and uncluttered noisefloor. This has the effect of releasing the music into space as it would happen in live performance.” Atkinson summed up the MOON’s performance in his test lab by writing that as a conventional integrated, the MOON 371’s measured performance with its analog line-level inputs and the digital inputs was very good. The phono input also did well on the test bench in both moving magnet and moving coil modes, with accurate RIAA equalization, very close channel matching, low harmonic and intermodulation distortion, and high overload margins. However, he did note that low-frequency noise in MC mode was higher in level than he expected. (Vol.49 No.5 WWW)

Musical Fidelity Nu-Vista 600.2: $10,999
The latest in a long line of Musical Fidelity amplifiers to utilize nuvistors, small, metal-clad vacuum tubes introduced in 1959 to compete with bipolar-junction transistors, the massive, dual-mono 600.2 is an extensive reworking of the original 600 from about 10 years ago. The input stage is implemented with nuvistors; the output stage comprises four complementary parallel pairs of transistors per channel. There are both single-ended and balanced inputs, as well as fixed line-level outputs and volume-controlled line-level outputs. Martin Colloms found that the 600.2 had a natural, rather analog character. “There was no sense of any power limitation during large dynamic peaks,” he wrote, adding that “that power came with precision, natural timbre, and a well-focused power in the bass; the bass impressed right away.” Colloms’s conclusion? “The Musical Fidelity Nu-Vista 600.2 is exceptionally powerful and load-tolerant and essentially neutral in timbre. It rewards listeners with fine transparency and detail.” In Paul Miller’s test lab, the 600.2 exceeded its specified power, delivering 200Wpc into 8 ohms and 325Wpc into 4 ohms. Distortion was low and very stable with respect to both temperature and frequency, he noted. (Vol.48 No.12 WWW)

Musical Fidelity Nu-Vista 800.2: $13,999
This updated version of Musical Fidelity’s original Nu-Vista 800 still uses nuvistor tubes for its small-signal circuitry, coupled with a solid state, class-AB, bipolar output stage that is specified as delivering 330Wpc into 8 ohms, 500Wpc into 4 ohms, and 1000W peak into 2 ohms. (In the test lab, the Nu-Vista 800.2 didn’t quite meet its specified output powers, clipping at 290Wpc into 8 ohms and 470Wpc into 4 ohms.) Inputs are one balanced line-level pair and four single-ended line-level pairs. John Atkinson found that the Musical Fidelity exerted superb low-frequency control, with an optimal combination of weight and articulation. He noted that the manner in which this amplifier retrieved a recording’s low-level detail was addictive. That, coupled with its tight grip on the speakers’ woofers, its sense of almost unlimited power, its superb soundstage definition, and a sense of ease to its presentation, won the Nu-Vista 800.2 an unreserved recommendation. (Vol.46 No.12 WWW)

Octave Audio V 70 Class A: $12,750; $17,100 as reviewed
This tubed amplifier can be fitted with KT88 or KT120 output tubes—the latter add $400 to the price—and its power supply can be reinforced with Octave’s Super Black Box, which costs $3500. An MC or MM phono board adds $850. Robert Schryer auditioned the fully loaded V 70 with KT120 tubes, which he felt gave a “more panoramic, harmonically developed, bassier, more dramatic presentation” than KT88s did. Listening to a mediocre-sounding Cannonball Adderley CD, he noted that “the Octave didn’t so much erase the digital nasties as allow more of the music to emerge so that I cared less about said nasties. … The Octave radiated the performance, making it big, robust, lustrous, alive, and emotionally galvanizing.” The V 70 “straddled the lines between tube efflorescence and solid state vigor, between low-powered intimacy and high-powered impact, between charisma and authenticity,” he decided. Removing the Super Black Box resulted in a general reduction in tonal color, soundstage size, instrumental separation, and sense of musical ease. Playing LPs with a MusiKraft Denon DL-103 moving coil cartridge, Schryer noted that the V 70’s characteristic transparency, big-picture boldness, and the detail retrieval he’d heard with digital came through, if not quite to the same level. The V 70 is specified as offering 50Wpc into 4 ohms with KT120s; in John Atkinson’s test lab, the output power at 3% THD+N was 38Wpc into 8 ohms and 57Wpc into 4 ohms with or without the Super Black Box. “The Octave Audio V 70’s measured performance is typical of a tubed amplifier that doesn’t use a large amount of corrective loop negative feedback,” concluded Atkinson, who wrote that while the lowest distortion at moderate powers was obtained with KT88s driving 8 ohms with the Power switch set to High, he doesn’t recommend this condition for loads below 8 ohms. “The KT120 tubes cope better with lower impedances,” he observed. (Vol.47 No.5 WWW)

Pass Laboratories INT-25: $8360 in silver; $8860 in black $$$ ★
To Herb Reichert, who prefers integrateds over separates yet wouldn’t even consider buying an amp with a built-in DAC—“Why would I pollute a fine audio component with a non-upgradable and possibly third-rate ancillary?”—the Pass INT-25 emerged as an ideal component. The remarkably heavy (51 lb) INT-25 is essentially a Pass XA25 power amp—class-A push-pull without degenerative feedback and offering 25Wpc—wedded to a minimalist line-level preamp. Used with his DeVore O/93 speakers and playing Erich Leinsdorf’s recording of Wagner’s Die Walküre, Herb found that “the INT-25 let the O/93s make that Die Walküre into something so beautiful I just laid back and basked in it.” He also felt the INT-25 is capable of putting across “a subtle radiance” that eludes other solid state electronics. With the amp on his test bench, John Atkinson found “much to admire in the Pass Labs INT-25’s measured performance.” Reichert’s last word: “my new solid state reference.” (Vol.43 No.2, Vol.46 No.2 WWW)

Pathos InPoL Legacy: $55,000
This massive, hot-running amplifier uses a front end based on two Tung-Sol ECC803 tubes and one Sovtek 6H30 tube for each channel used in a totem-pole configuration. The output stage uses MOSFETs operated in single-ended, class-A mode and controlled by this Italian manufacturer’s unique InPoL circuitry. The solid state output stage “follows” the tube stage’s voltage, while acting as a high-current “pump.” The tubes provide all the voltage gain and shape the sound; the solid state circuit delivers “muscle” to drive the loudspeakers. A circular display in the center of the volume control shows the volume, up to “99.” Rogier van Bakel found this display too bright and that the volume control needed a touch too much elbow grease to operate, but those were his only substantive criticisms. He was impressed by the amplifier’s sonic character; the word he kept coming back to was generosity. “The Pathos amp had a bounteous presentation that expanded the soundstage in all directions,” he wrote. “With most recordings, Pathos’s Italian thoroughbred mirrored its immodest physical dimensions with an immense soundstage. I don’t recall hearing another amplifier in my system that delivered width, depth, height, and life quite like this bodacious beauty,” he concluded. In Paul Miller’s test lab, the InPoL Legacy exceed its specified 100W into 8 ohms, offering 160Wpc into 8 ohms, before falling back to 105Wpc into 4 ohms. Distortion was very low in level, despite the circuit not using any global negative feedback. “This amplifier is powerful enough for medium sensitivity loudspeakers of, preferably, 6 ohm nominal impedance and above,” he concluded. (Vol.48 No.7 WWW)

PrimaLuna EVO 300 Hybrid Integrated: $6995
A hybrid design with a tubed front-end and driver stages and an output stage that combines JFETs and MOSFETs, the EVO 300 is specified as outputting 100Wpc into 8 ohms and 160Wpc into 4 ohms. There are five pairs of single-ended inputs, one pair of single-ended home theater bypass jacks, and headphone, subwoofer, and tape outputs as well as the usual speaker outputs. Ken Micallef wrote that he was immediately taken by the EVO 300’s energy, immediacy, and drive, and commented on the panoramic stereo stage. “This is an amplifier that allows music to breathe, opening up a window that was one of the purest I’ve experienced,” he enthused, adding that “From the first note, the EVO 300 established itself as a modern classic, reproducing music fresh-scrubbed, juicy, spatially adroit, dynamically adept, and powerful. It possessed the liquidity and richness of a good tube amp, never crossing over into syrup or schmaltz.” On the test bench, the EVO 300 exceeded its specified powers, clipping at 115Wpc into 8 ohms and 170Wpc into 4 ohms. The distortion waveform was predominantly the subjectively benign second harmonic, which will offer a hint of “tube sound.” The PrimaLuna amplifier ran hot: “This amplifier needs plenty of ventilation,” John Atkinson advised. (Vol.47 No.8 WWW)

Quad Platina: $5495
See Herb Reichert’s review on p.157. (Vol.49 No.10)

T+A R 2500 R: $19,990
Possibly the most comprehensively equipped receiver Stereophile has reviewed, the R 2500 R offers radio (FM, digital FM, internet-streaming), CD playback (through the slot-loading built-in player), computer audio (through the built-in USB DAC), streaming services (via hard-wired Ethernet or Wi-Fi), Bluetooth and Apple Airplay connectivity, TV sound (optical S/PDIF or HDMI-ARC digital through the DAC), digital files from a thumb drive or hard drive (connected via USB), and line-level analog input. There is also an optional MM/MC phono stage ($920). There is a headphone output as well as two pairs of speaker outputs, all of which can be independently selected or muted. The R 2500 R was waiting for Roon certification at the time of the review—Tom Fine tried the T+A with Roon in a follow-up review—but music can be streamed with T+A’s MusicNavigator G3 app. The DAC offers four oversampling digital filters and two nonoversampling filters for PCM and two for DSD—Fine preferred the “Bezier” oversampling filter for PCM. Fine wrote that music sounded pretty damn good from the get-go. After letting the R 2500 R break in for two weeks, he couldn’t say there was a radical improvement, “maybe slightly more extended bass and a tiny bit more air, space, and reverb tails.” With PCM data, the R 2500 R’s DAC was in keeping with the very best modern DACs in that it was ultrarevealing and transparent. Playing DSD files ripped from SACDs, Fine heard a clarity and naturalness that not all DACs seemed able to convey from DSD material. The class-AB output stage offers maximum powers of 140Wpc into 8 ohms and 250W into 4 ohms, which were slightly exceeded in the test lab. “The T+A R 2500 R’s power amp comported itself well,” he wrote, noting that while it didn’t exhibit quite the masterful control of his reference Benchmark AHB2, “it was damn good and satisfying. There was no mud or crud at the bottom.” Summing up, Fine wrote that the T+A R 2500 R “offers almost limitless music-listening options in a handsome, relatively compact component. Add a pair of good speakers, and you’re off to the races. It is premium priced, for sure, but it offers premium sound.” When John Atkinson installed and measured the phono stage, he commented that it offered accurate RIAA equalization, low noise, and very low distortion. However, it was incompatible with tonearms, like the Regas, that reference the cartridge output to ground. When Fine auditioned the phono stage he noted how quiet it sounded: “Even at the elevated volume levels appropriate for classical records, no hiss, hum, or hash was audible at the listening seat.” Listening to some favorite records, he found that the T+A’s upper mids and treble “sounded right.” (Vol.47 No.8, Vol.48 Nos.1 & 2 WWW)

Thöress EHT MKII: $13,999
This hybrid tube-input/MOSFET-output amplifier offers up to 20Wpc into 6 ohms. A toggle switch allows the user to choose flat (the middle position) or either of two bass-boost settings, B1 or B2. When Herb Reichert first tried B1, he thought it was a trick—that the setting was rolling off the treble to bring the bass and midrange up. “But as I listened more carefully,” he wrote, “alternating between B1 and flat, I found that the slight swell, maybe 5dB around 80–90Hz, was adding length and fullness to reverb sounds.” Overall, however, he preferred the flat setting, when the EHT “portrayed reverb in a manner so natural (energy- and focus-wise), it was hard to remember to listen for it.” Reichert used this amplifier to drive DeVore O/93, Falcon Gold Badge, and Heretic AD614 speakers and commented that the EHT “specializes in naturally rendered contrasts, a rare virtue.” He summed up his time with it by writing, “The Thöress EHT was created to deliver high-toned elegance, conspicuous musicality, and gratifying precision to easy-to-drive speakers like the ones I used it with. That’s its raison d’être and the reason I recommend it.” (Vol.46 No.10 WWW)

Triode Lab 2A3 EVO Mk.2: $8999
A Canadian single-ended triode (SET) amplifier, the EVO Mk.2 is tube rectified and uses Electro-Harmonix 2A3 EH or Kalman Rubinson Audio 2A3 output tubes and Hashimoto Electric output transformers to generate up to 3.5Wpc into 8 ohms. John Atkinson found that the 2A3 EVO fitted with the Rubinson tubes delivered 4.3Wpc from the 8 ohm tap into 8 ohms and 4.1Wpc from the 4 ohm tap into 4 ohms, both at 10% THD+N! (The Electro-Harmonix tubes gave similar powers but with slightly higher distortion at low powers.) Fortunately, the distortion was predominantly the subjectively innocuous second harmonic. Ken Micallef’s sample included the upgraded choke option ($250) and, using appropriately high-sensitivity speakers, he noted that the low-power 2A3 EVO brought “fleshy textures, rich tonal color, a sense of naturalness—and, yes, flow,” which he’d found evades some SETs. “Music breathed. It sounded sweet, round, voluptuous, as if the amp itself was relaxed, inviting me to sink deeper and lose myself in the sound,” he wrote, adding that “its richness never dampened its clarity or the clarity of instrumental or vocal lines.” A product with narrow application, but if your need is for a flea-watt tube amp, it’s class A. (Vol.47 No.7 WWW)

Unison Research S6 Black Edition: $7499
This tubed integrated amplifier uses three KT77 Gold Lion output tubes in single-ended Ultralinear mode for each channel to deliver a specified maximum power of 40Wpc into 6 ohms at 5% THD. (John Atkinson measured 38W into 8 ohms at 10% THD+N.) There are four pairs of single-ended inputs as well as USB, S/PDIF, and TOSLINK digital inputs; the USB input supports PCM up to 384kHz and DSD up to DSD256. (The DAC chip is a Sabre ES9018K2M.) Listening to vinyl, Ken Micallef noted that the S6 Black Edition made music with a dark-chocolatey richness while managing to avoid cloying sweetness or sentimentality. Its presentation was vibrant and full. “No matter what I paired it with, the S6 Black, with its signature golden hue and consistent well-sortedness, faithfully reproduced subtleties of the upstream and downstream components,” he wrote. The S/PDIF digital input fared less well: “the sound was perfectly fine: quiet, even compelling, but nowhere near as engaging as my analog setup.” Micallef’s conclusion? The Unison Research S6 Black Edition does have a sound of its own, “classic tube sound: liquid, a touch warm, excellent tonal color. It’s not old-fashioned or stodgy, but it’s definitely not sterile.” In the test lab, the S6 Black Edition behaved pretty much as Atkinson expected from a tube amplifier with a single-ended output stage and little or no global negative feedback. “While the distortion signature is predominantly the innocuous second harmonic,” he wrote, “the high levels of distortion at powers of more than 1W, especially into impedances below 8 ohms, mean that this amplifier must be used with loudspeakers that have both a high sensitivity and a high impedance.” (Micallef auditioned the S6 Black Edition with the very sensitive Volti Lucera and Voxativ Ampeggio loudspeakers.) “The measured performance of the digital inputs was compromised by the presence of supply-related spuriae,” Atkinson found. (Vol.48 No.5 WWW)

Vitus Audio RI-101 Mk.II: $22,313 standard colors
With optional DAC/streamer module: $27,563
The sound of this Danish solid state integrated amplifier impressed Jason Victor Serinus, who wrote that the sound “was enticingly full and colorful. Focus and solidity were impressive.” He felt that the RI-101 Mk.II’s bass wasn’t as strong, tightly focused, and refined as that from his far more expensive reference monoblocks, commenting that the bass timbres “were slightly off, a bit soft and powdery in the center and lacking the last iota of resonant overtones.” He added, however, that this hardly diminished his enjoyment of music. Using Roon to stream files through the Vitus’s optional streamer/DAC board, Serinus heard a surprising amount of detail. Piano could have sounded richer and voice more substantial, he felt, but color and midrange warmth were right on and seductive. “If you’re looking for an integrated with optional DAC/streaming capabilities that you can live with for a long, long time,” he concluded, “the Vitus RI-101 Mk.II is solidly recommended.” Rated output power is a very high 300Wpc into 8 ohms and 600Wpc into 4 ohms. John Atkinson measured 290Wpc into 8 ohms but 410Wpc into 4 ohms at 1% THD+N and 470Wpc at 3% THD+N. (The shortfall in 4 ohm power was most likely due to the wall AC voltage drooping at these powers.) The RI-101’s output stage is said to transition from class-A to class-AB at approximately 8W into 8 ohms, and Atkinson did note crossover distortion at 50W into that load. The Streamer digital inputs featured a long minimum-phase reconstruction filter, but a higher-than-expected noisefloor limited measured resolution. (Vol.47 No.6 WWW)

B:

AVM Inspiration CS 2.3: $7999 in black or silver finish
A small integrated amplifier with a class-D output stage that integrates a CD drive, offers Ethernet, Wi-Fi, and Bluetooth connectivity and has coaxial S/PDIF, HDMI, and USB-A digital inputs, two sets of single-ended, line-level analog inputs and one MM/MC phono input with loading plugs. (The analog inputs are not converted to digital.) There are two TOSLINK digital outputs; analog preamplifier and subwoofer outputs; a headphone jack, and a pair of small binding posts for loudspeakers. Control can be with the front panel control buttons or AVM’s iOS and Android RC X apps. Stephen Mejias found the app intuitive and a pleasure to use: “Navigating menus and submenus felt logical and appropriate.” He concluded that while the C S2.3 is not inexpensive, “when you price out everything it does—DAC, streamer, CD player, line and phono preamp, amplifier, headphone amp—and how well it does it, the smallness of that number starts to impress.” In the test lab, John Atkinson found that the AVM met its specified power of 140Wpc into 4 ohms, the CD transport featured superb error correction, the DAC offered high resolution and a choice of reconstruction filters, and the phono input had superbly accurate RIAA correction and low noise and distortion. He did comment, however, that the amplifier will probably work best with speakers that have an impedance greater than 4 ohms. (Vol.46 No.6 WWW)

Eversolo Play CD Edition: $799 $$$
The budget-priced Play CD Edition is a Roon Ready music streamer, class-D amplifier, preamp, DAC, and CD player, all housed in a small square box measuring just 9" × 3" × 9". The front panel is dominated by a 5.5" color touch display and a large volume control knob that can be used to navigate the setup menu and input selection. The Play can also be controlled with a smartphone app, which integrates directly with Tidal, Qobuz, Amazon Music, Deezer, etc. On the back panel are an Ethernet port; a USB 3.0 port, an HDMI-ARC port, TOSLINK and coaxial S/PDIF inputs, two pairs of line-level analog inputs, and an MC or MM phono input. There’s also a preamp output pair, a single subwoofer output, and a coaxial S/PDIF data output. CDs are played with a Hitachi-LG optical CD-ROM assembly with a vibration-dampening chassis. CDs can also be ripped to the Play’s 32GB of built-in storage, and if that isn’t enough there are 24 EQ presets, a 10-band graphic EQ, a 10-band parametric EQ, and the ability to implement room correction using a smartphone microphone. “After a couple of weeks with the Eversolo, I realized that, with some exceptions, I liked how it rendered music I know well,” wrote Rogier van Bakel, though he noted that music could sound slightly dry on the dynamic peaks in some orchestral works. Even so, he concluded that the Play won him over in minutes. “Eight hundred bucks is a pittance for an audio component that can singlehandedly function as the heart of a reputable home system, and I can’t fault the Play on any serious metric.” In John Atkinson’s test lab, the Play featured superb error correction with CDs, offered a measured digital resolution of 18 bits, had low levels of primarily second-harmonic distortion, and exceeded its specified output power of 60W into 8 ohms clipping at 74Wpc with a 1kHz signal and at 81W with a 20kHz signal. Although van Bakel wasn’t able to audition the Play’s phono stage, Atkinson found that the phono stage offered excellent measured performance in both MM and MC modes, with very low distortion and noise despite being housed in a small chassis with a large display, a CD transport, a D/A processor, class-D amplifier circuitry, and a switch-mode power supply. (Vol.49 Nos.1 & 3 WWW)

Hegel H400: $7700
As well as balanced and single-ended line inputs (but no phono input), this Norwegian integrated amplifier includes optical and coaxial S/PDIF inputs as well as USB and Ethernet ports. The DAC is based on an ESS Sabre ES9038Q2M chip and that company’s Hyperstream II architecture, with built-in jitter correction. Although the ESS chip offers a choice of different reconstruction filters, Hegel’s designers chose what they think sounds best: “an apodizing filter without pre ringing.” At the time of the review the H400 supported Spotify, Tidal Connect (but not Qobuz Connect), Apple AirPlay, and Google Chromecast, though there is no Wi-Fi or Bluetooth connectivity. The H400 can also access a networked local music collection via the UPnP protocol. Tom Fine streamed music with Hegel’s Connect app and the JPLAY app. He summed up the H400 by writing that considering the amplifier’s power, build quality, and full-function built-in streamer with app control, it’s quite a value. “Add the amplifier’s excellent sound quality and tight control of various speaker loads, and the H400 is worth a close look if you’re in the market for a future-facing integrated amplifier.” Following the publication of Fine’s review, the H400 was certified Roon Ready. In his followup, Fine reported that the H400 worked perfectly with Roon and decided that Roon was the best way to do streaming with it. On the test bench the H400 did not meet its specified output power of 250W into 8 ohms, clipping at 225Wpc. However, Hegel notes that the specified power into 8 ohms is “Dual-Mono,” and with just one channel driven, the H400 missed its specified power by a negligible 0.1dB, clipping at 247W. With both channels driven the amplifier clipped at 340Wpc into 4 ohms. Overall, Hegel’s H400 offered generally excellent measured performance with both analog and digital input signals, decided John Atkinson. (Vol.47 No.10, Vol.48 No.1 WWW)

HiFi Rose RA280: $3395
The RA280’s class-D output stage uses GaNFETs (gallium nitride field effect transistors), with a specified output power of 250Wpc into 4 or 8 ohms. (John Atkinson measured 300Wpc into 8 ohms at 1% THD+noise and 305W at 0.053% THD+N into 4 ohms, when the amplifier went into protection mode.) There are both balanced and single-ended inputs and a subwoofer output as well as two pairs of speaker outputs. The phono stage is suitable for moving magnet cartridges. While Ken Micallef, playing both LPs and CDs, found the overall presentation to be slightly dry, which contributed to sharp image focus, he heard fantastic punch, a strong sense of flow, intimacy, and physicality. “I was caught up in the life force and drive the RA280 extracted from recordings,” he wrote, concluding that the HiFi Rose RA280 “delivers a wealth of sonic virtues out of proportion to its price. It’s a powerful amplifier with unflagging drive, excellent separation of instrumental lines, tonal richness, wide-open focus, lucidity, tangible, physical images, and intense dynamics.” (Vol.48 No.11 WWW)

HiFi Rose RS520: $3995 ★
The Roon Ready RS520 marries a GaNFET-based class-D amplifier to the large, 12.25" wide front-panel touchscreen featured on the Korean company’s streaming D/A processors. It offers a plethora of audio and video streaming functionality, as well as offering optical and coaxial S/PDIF inputs, USB ports for attaching local storage, and WiFi and Bluetooth connectivity. Rogier van Bakel controlled the RS520 with the HiFi Rose smartphone app and with all the speakers with this he used the amplifier found that there was weight, control, authority, clarity, and palpability. “I heard sweet detail up top that didn’t become brittle even on borderline sibilant recordings,” he wrote, concluding that the HiFi Rose is “a fast, impressively appointed sports car for the price of a Volkswagen Golf. Fahrvergnuügen indeed!” In the test lab, the RS520 offered generally excellent measured performance, offering a clipping power of 275Wpc into 8 ohms and a DAC with a choice of multiple reconstruction filters and between 19 and 20 bits of resolution. However, John Atkinson noted that the class-D output stage had a higher level of ultrasonic noise than he usually finds with such designs. (Vol.46 No.7 WWW)

Leak Stereo 230: $1995 with wood enclosure $$$
This retro-styled integrated amplifier combines old-world features—a phono stage, headphone jack, and tone controls—alongside new-world ones including hi-rez streaming up to 32/768 PCM, native DSD512, full MQA decoding, aptX HD Bluetooth, and HDMI ARC connectivity. The class-A MOSFET output stage offers 75Wpc into 8 ohms and 115Wpc into 4 ohms. (John Atkinson measured 80Wpc into 8 ohms and 120Wpc into 4 ohms.) Listening to digital, Robert Schryer wrote, the Leak’s overriding character “was one of musical buoyancy disposed of light and color, with an effortless liftoff of notes,” coupled with a sense of soundstage integrity. He found that these qualities extended to the amplifier’s JFET-based MM/high-output MC phono stage, though he did concede that the 230’s highs might not have been as airy or extended as those from some of the more expensive gear he’s heard. Overall, “the 230 is an example of how far the sound quality and versatility of affordable audiophile gear has come in the last few years. … I didn’t hear a $1500 product; I heard a well-designed product regardless of price.” Atkinson’s findings? “The Leak Stereo 230 amplifier offers excellent measured performance from all of its inputs,” he wrote, noting that the digital inputs offer around 19 bits’ worth of resolution and the phono input featured very low noise and distortion. (Vol.47 No.1 WWW)

Line Magnetic LM-845IA: $4995 ★
Replacing Herb Reichert’s long-term reference tube amplifier, the LM-518IA, the Chinese LM-845IA weighs a back-breaking 77 lb and still uses a single hot-running 845 tube for each channel’s output, but has internal component changes and redesigned output transformers, these sourced from Japan. It also uses 12AX7 input tubes, a 5AR4 rectifier, and a pair of triode-operated 6P3P beam tetrodes to drive the grids of what Alex Halberstadt described as “those slightly terrifying 845s.” The Line Magnetic offers 4, 8, and 16 ohm speaker terminals, three line-level inputs, and a preamplifier input for those wishing to use the LM-845IA as a power amplifier. A nicely machined aluminum remote with volume and mute buttons is included. What Halberstadt noticed first in his auditioning were “the hallmarks of a well-designed single-ended triode (SET) amplifier: a bell-like clarity, lots of textural information, and a distinctive three-dimensionality to the sonic images. … With the Line Magnetic and the 16 ohm taps, the soundstage was expansive in width, height, and depth, with instruments and voices floating free of and well above my Altec Valencia 846A speakers.” The LM-845IA’s maximum power is specified as 22W. John Atkinson found that with our usual definition of clipping, which is when the output’s THD+noise percentage reaches 1%, with both channels driven with a 1kHz signal the LM-845IA’s 16 ohm tap clipped at just 2Wpc into 16 ohms, though it did offer the specified 22W from this tap at 3.5% THD+N. Unusually, the Line Magnetic’s 16 ohm and 8 ohm output transformer taps worked best with impedances that were lower than the nominal tap value. However, these two taps have sufficiently high output impedances that the LM-845IA’s sonic character will be different with every loudspeaker with which it is used. The 4 ohm tap has a lower output impedance, Atkinson noted, but this is at the expense of higher distortion, even at low powers, than the higher-impedance taps. He did find, however, that the LM-845IA was significantly quieter than its predecessor. Class B rating reflects high output impedance, which means performance will depend on the loudspeaker used. (Vol.44 No.7 WWW)

Musical Fidelity A1: $1999 $$$
Looking almost identical to the hot-running, class-A, Tim de Paravicini–designed original from the late 1980s, Musical Fidelity’s new A1 uses a wider, thicker chassis, with more heatsink area, a bigger transformer and power supply, better circuit boards, more capacitance, closer tolerance, parts rated for higher temperature, beefier binding posts, more ventilation holes on the sides, one MM/MC phono input, and five single-ended line-level inputs. The A1’s output stage is rated to deliver 25 pure class-A watts into 8 ohms. Listening with Nagaoka’s MP-200 cartridge, Herb Reichert found himself grinning at the volume and extensive detail of the projected soundspace. “Tone and texture were super vivid,” he wrote. Maximum gain can be set 32dB in Direct mode, 42dB in Normal mode. Comparing the two modes, Reichert initially felt there was a change in sound character, but it was not dramatic. However, the longer he listened in Direct Mode, the brisker, cleaner, and more enticing it seemed. On the test bench the phono stage offered low noise and distortion and high overload margins in both MM and MC modes. The A1 slightly exceeded its specified output power of 25W into 8 ohms, clipping in both Normal and Direct modes at 30Wpc. Musical Fidelity doesn’t specify the maximum power into 4 ohms, but with both channels driven, the amplifier delivered 31Wpc into 4 ohms at 3% THD+N. John Atkinson concluded that the Musical Fidelity will work best with loudspeakers whose impedance remains above 4 ohms, though the fact that its distortion signature is dominated by the subjectively benign second harmonic will work in its favor with more demanding loads. (Vol.47 No.10 WWW)

NAD M10 V3: $3199
The Roon Ready M10 V3 looks identical to the M10 that John Atkinson reviewed in January 2020. It still uses a “DirectDigital” Hypex nCore class-D output stage, but the DAC is now a 32-bit, 768kHz Sabre ES9039 chip and the reconstruction filter is a minimum-phase type rather than the original linear-phase filter. A free license to use Dirac Live LE Room Correction is still included, along with a USB microphone, but there is now a remote control and a moving magnet phono stage. As well as Roon and the BluOS app, the M10 now works directly with the Qobuz Connect, Spotify Connect, and Tidal Connect apps. Using Dynaudio Contour 20 Black Edition loudspeakers, Atkinson felt that after he had accommodated to the gain with digital sources being 7dB greater than with the original M10, the V3’s presentation was overall very close to that of the M10 V1. He did find that the V3’s treble was slightly less forgiving than the V1 of recordings that were overcooked in this region. Nevertheless, he was surprised by how close the NAD’s presentation got to that of his regular MBL/Parasound big rig at just 6% of its price. He was also impressed by the new phono stage, finding it sounded sweet, though with no lack of high-frequency detail. Atkinson concluded that the M10 V3 was a worthy successor to the original M10, preserving all the performance and operational aspects that he liked while adding an excellent MM phono stage. (Vol.49 No.1 WWW)

NuPrime MCX-800D: $3995 $$$
This 8-channel class-D amplifier has both digital inputs (USB and TASCAM-standard DB25) and single-ended and balanced line-level analog inputs. The digital inputs support stereo (PCM to 32/768, DSD Native to DSD256), eight channels (to 32/192), and six channels (DSD Native to DSD128). There are switchable line-level outputs as well as loudspeaker outputs. Kalman Rubinson started his auditioning by using a digital source with the MCX-800D’s speaker outputs connected to his left, center, and right channels while sending line-level outputs to his left-side and right-side powered speakers and powered subwoofers. “The sound was excellent,” he wrote, and with a multichannel vocal recording “all the instruments and voices were clear and warm, delineated with an inviting presence just a few feet beyond the speaker plane.” Playing the same recording with the outputs of his reference multichannel D/A processors feeding the NuPrime’s analog inputs, the sound was marginally more direct and incisive, but the previously noted warmth in the shaping of the voices was maintained. With a 5.1, 24/352.8 set of Beethoven symphonies, Rubinson noted that the tonal flavors of all the instruments, solo or tutti, were natural and distinctive, with no high-frequency glint. “Their places in the soundfield were not spotlighted but were as they would be from Row H, center, at subjectively similar SPLs.” Rubinson summed up his time with the NuPrime MCX-800D by writing “It could serve as the electronic core of a complete multichannel audio system much more than competently. This single box can select, decode, and amplify high-quality music sources to energize an array of speakers that require considerable power.” Rated output power is 120Wpc into 8 ohms and 220Wpc into 4 ohms; John Atkinson measured the MCX-800D’s clipping power with two channels driven into 8 ohms as 117Wpc. However, the amplifier went into protection mode at 139Wpc when he examined the maximum power into 4 ohms. Atkinson found that the NuPrime produced very low levels of harmonic and intermodulation distortion with both analog and digital data, as well as a measured resolution between 18 and 19 bits and superb rejection of data-related jitter with the latter. (Vol.49 No.1 WWW)

Onkyo Icon A-50: $1599.99 $$$
The full-functioned, Roon Ready Icon A-50 includes an MC/MM phono preamp, three line-level analog inputs, a USB-C input (for a thumb drive full of music files), an HDMI-ARC socket—for using the A-50 with a video screen—optical and coaxial S/PDIF inputs, a preamp output, and connection to the home network via either a Wi-Fi antenna or an Ethernet cable. DSP facilities include a form of loudness equalization calibrated to the system’s speakers and listening seat location, and Dirac Live room correction. A linear power supply is used for all analog and most digital functions. A small switch-mode power supply keeps the A-50 connected to the network during standby. Tom Fine found that he had a lot of fun listening to the Onkyo A-50. It is amply featured and does most of what it does very well. The design is smartly considered and well-executed. Its look and finish proudly declare “high quality.” “For your $1600, you get a lot of stuff in a handsome, reasonably sized package. If you’re streaming-centric, this is all you need except for a good pair of speakers,” he concluded, adding that the A-50 “fits the definition of ‘High-Value Component.’ It firmly places rejuvenated Onkyo—the company—on the radar of hi-fi shoppers seeking excellent sound and solid build on a lunchpail budget.” Output power is specified as 110Wpc into 8 ohms; John Atkinson measured a clipping power of 135Wpc into 8 ohms with both 1kHz and 20kHz signals. He concluded that while the Onkyo A-50’s measured performance with its analog line-level inputs was very good, the measured performance with digital inputs was respectable, but only when there was a ground connection between the amplifier and the audio data source. He also noted that while the phono input in moving magnet mode did well on the test bench, the moving coil mode was compromised by the presence of high-level infrasonic noise. Extraordinary value. (Vol.49 No.4 WWW)

PrimaLuna EVO 400 Integrated: $6495 $$$ ★
The Dutch company’s new top-of-the-line integrated tube amplifier uses six 12AU7 mini triodes and four pairs of EL34 output tubes, which can be operated in Triode or Ultralinear mode. (Higher-power KT-150s can also be used.) The EVO 400 offers 4 ohm and 8 ohm output transformer taps, and there are also headphone, tape monitor, and line-level subwoofer outputs. (An optional moving magnet phono stage costs $249 but wasn’t fitted to the review sample.) The circuitry is almost entirely hard-wired—no printed circuit boards are in the signal path. Rogier van Bakel commented on the PrimaLuna’s extraordinary clarity and detail retrieval. He compared the two output tube modes and wrote that Ultralinear provided the clearest lens into the music, Triode taking the edge off. At low frequencies, he sometimes heard less control in the bass than he does with solid state amplifiers. “But the music chugged and jived in ways that left no room for disappointment,” he noted. The EVO 400 is specified as offering maximum powers of 38Wpc into 8 ohms in Triode mode and 70Wpc into 8 ohms in Ultralinear mode. John Atkinson measured 63Wpc into 8 ohms at 1% THD+N in Ultralinear mode, and the specified 70Wpc at 3% THD+N. In Triode mode, the 8 ohm tap gave 33Wpc. Atkinson concluded that the PrimaLuna EVO 400’s measured performance was what he would expect from an amplifier with a push-pull output stage that uses paralleled EL34 tubes. The test results suggest that the lowest distortion will be obtained from the 4 ohm tap in Ultralinear mode. (Vol.45 No.6 WWW)

Rogue Audio Sphinx V3: $1795 $$$ ★
Descended from the original Sphinx that Herb Reichert reviewed in 2014, the V3 is still “an old-school, 25 lb, made-in-America integrated amplifier with three line-level inputs … and a 12AU7-based, mu-follower preamplifier stage driving a 100Wpc (into 8 ohm), class-D, solid state power amplifier.” The phono stage now has adjustable loading and gain so it can be used with both MM and MC cartridges. (The RIAA correction incorporates the IEC-recommended low-frequency rolloff, reaching –3dB at 30Hz.) Headphone output is now based on discrete MOSFET devices, which John Atkinson found led to a very low source impedance, appropriate even for low-impedance cans. With CDs, Reichert found that the Sphinx V3 “delivered a good amount of leading-edge bite and trailing-edge flow. Bass felt quicker and more articulate. The V3 displayed a fun, taut energy the original did not have.” He tried the phono input with the Ortofon 2M Black moving magnet and Hana Erick Lichte moving coil cartridges and concluded that “The Sphinx V3’s MM/MC phono input did proclaim the virtues of analog.” Reichert summed up the V3’s headphone amp as “not as powerful, dynamic, or transparent as the Schiit Ragnarok’s, but it’s closer to that than any others I’ve auditioned.” Overall, he summed up the Sphinx V3 as “an unpretentious working-person’s amplifier. It delivers music with an eager expressive energy, in concert with a forgiving musical nature.” On the test bench, the V3 didn’t quite meet its specified power, clipping at 96Wpc into 8 ohms, and the phono stage’s RIAA equalization was slightly mismatched between the channels, with the right channel up to 0.9dB higher in level in the treble than the left. (Vol.43 No.8,Vol.46 No.2 WWW)

T+A Symphonia: $10,990
This full-function device features single-ended line and MC/MM phono inputs, two USB and two S/PDIF (coaxial and TOSLINK) digital inputs, an HDMI ARC bus, a Roon Ready Ethernet port, two Wi-Fi antennas, and a 75 ohm antenna jack to receive FM radio. Music can be streamed from Qobuz Connect, Tidal Connect, Amazon Music, etc, easily selected with the T+A MusicNavigator G3 app for mobile devices. The class-D output stage uses Purifi Eigentakt technology that T+A licenses then puts its own spin on. There is a 4.4mm Pentaconn headphone output. Comparing the Symphonia with the 2024 Quad pre/power combo with an orchestral recording streamed with Qobuz, Rogier van Bakel noted that there was more bass grip, more color, more engagement. With other recordings “the clarity was fantastic.” He concluded that “With its crisp dynamics, taut, brawny bass, and feather-light treble detail, the Symphonia drew me in, unfailingly. It delivers way more audiophile gravitas than its size suggests.” Tom Fine auditioned the phono stage set to MM mode and noted both the neutral sonic signature and how quiet the amplifier was. He concluded that the Symphonia sat on the right side of his “90% rule”: “It’s fine for 90% of the turntables and cartridges out there and for playing 90% of records 90% of the time.” In the test lab, the Symphonia slightly exceeded its specified output powers of 125W into 8 ohms and 250W into 4 ohms, clipping with a 1kHz signal at 135Wpc into 8 ohms and 265Wpc into 4 ohms. Commendably, with a 20kHz signal it clipped at the specified power into 8 ohms. T+A’s Symphonia offered generally excellent measured performance with both digital and analog input signals, offering high power combined with very low distortion, noted John Atkinson. Other than a small boost in the low bass, the T+A Symphonia phono module’s measured performance was excellent, with otherwise accurate RIAA equalization and very low noise and distortion in both MM and MC modes. (Vol.48 No.11, Vol.49 No.1 WWW)

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Fern & Roby Amp No. 2: $8500
Herb Reichert was impressed by this elegant-looking US-made amplifier, which features balanced and single-ended line inputs and an internally switchable MM/MC phono input. With line-level sources, he noted that the Fern & Roby’s demeanor was “crisp, naturally focused, and superathletic, with excellent flow and boogie. It doesn’t sound solid state. Or soft. Or tubey. Or anything but exciting.” What he enjoyed most in using the Amp No. 2 was how it succinctly conveyed contrasting elements: “loud and quiet, far and near, present and absent, foggy and clear.” With an EMT moving coil, Reichert noted that the sound of the phono input was “bright lighting-wise, exceedingly clear and resolved,” though he noted that while bass was clean, perky, and tight, it was not as relaxed or heavy loping as it should be. With the phono input set to moving magnet and using an Ortofon 2M Black cartridge, Reichert found the sound satisfyingly rich, relaxed, and refined, with excellent soundspace depth, though macrodynamics felt less macro. Overall, the No. 2 presented music “with a vital, spirited charm that I found pleasantly addictive and deeply satisfying,” Reichert concluded. The Amp No.2’s maximum power is specified as 25Wpc into 8 ohms, which was confirmed by John Atkinson’s measurements. However, while he noted the low levels of harmonic and intermodulation distortion, he was concerned about a level mismatch between the channels and the unflat RIAA correction, the least accurate he has ever measured. In his Manufacturer’s Comment, Fern & Roby’s Christopher Hildebrand wrote that all the problems identified in the technical review had already been addressed in their production units. (Vol.47 No.6 WWW)

WiiM Amp: $329 $$$
Sold exclusively by Amazon, the Roon Ready WiiM Amp can play locally stored digital files and stream audio from the interwebs via Wi-Fi, Bluetooth, or Ethernet. It also offers optical and HDMI-ARC digital inputs, a USB port, and line-level analog inputs (the latter digitized at a 48kHz sample rate). Maximum class-D power is 60Wpc into 8 ohms and 120Wpc into 4 ohms. The Amp can be controlled with an Alexa-based voice-activated remote control or with the WiiM Home app, available for Apple and Android. The app features DSP-realized tone controls, graphic and parametric equalizers, and a host of EQ presets. There is an RCA output for a powered subwoofer, switchable on and off from the app. When a subwoofer is plugged in, the app allows the crossover to be set in the range of 30–200Hz. Tom Fine commented that the WiiM’s sound was what he calls “modern—punchy and somewhat sharp-edged.” He also noted that the upper midrange had a slight “class-D glaze” and that while low frequencies had “plenty of oomph,” there was not a sharp representation of the whole sound. Fine concluded that for a young audiophile or someone on a limited budget who decides the “smart speaker” or TV soundbar isn’t getting it done, the WiiM Amp is almost a no-brainer. In the test lab, the WiiM Amp slightly exceeded its specified powers and offered low distortion and noise and good rejection of word-clock jitter. John Atkinson commented on the digital inputs’ well-managed gain architecture and found that the DAC’s single reconstruction filter was a conventional linear-phase type. (Vol.47 No.7 WWW)

Deletions
Fezz Audio Silver Luna Prestige, discontinued. Audio Research I/50, replaced by newer model not yet reviewed. Ayre Acoustics EX-8 2.0 Integrated Hub, Naim Audio Uniti Nova, Pathos InPoL Remix MkII, HiFi Rose RA180, NAD C 3050, Roksan Attessa Streaming Amplifier, Rogue Audio Pharaoh II, Marantz MODEL 40n, Western Electric 91E, not auditioned in a long time.