Recommended Components 2020 Edition Preamplifiers

Two-Channel Preamplifiers

Editor's Note: Apart from the Bespoke, CAT, Placette, and Shindo, all the Class A preamplifiers offer balanced inputs and outputs. And unless noted, the preamplifiers listed do not have phono stages.

A

AVM Ovation PA 8.2: $10,595 base price; $19,995 as reviewed
A modular preamplifier that can be configured in a variety of ways, the Ovation PA 8.2 prevents the listener from having to invest in unwanted features, while taking into account the ever-changing world of digital audio: As technology progresses, AVM's current digital-input card ($3395), which supports up to 32/384 PCM and DSD256 and has both USB and S/PDIF inputs, can conceivably be replaced with even mightier modules. Other available input cards include an MM/MC phono preamp ($2395), a line input card with both balanced and unbalanced inputs ($1795), and a Line Input Tone Card ($2195) that provides tone and balance controls for all analog modules. The user also has a choice of output cards, including an optional Tube Output card ($3395) fitted with two dual-triode vacuum tubes. (A headphone amp and remote handset are included in the base price.) With line-level sources, Mikey noted "ultra-low" noise, "very high" transparency, "very good" dynamic expression, and "impressive" frequency extension and balance. In his view, the phono input offered "a level of sonic sophistication well above that of any $2400 phono preamp I've heard." In measuring the AVM preamp, JA noted "usefully low" output impedance, a distortion signature that was primarily second harmonic, and "superbly low" RIAA error from the phono card. "Overall," he wrote, "AVM's Ovation PA 8.2 offers superb measured performance." (Vol.41 No.12 WWW)

Ayre Acoustics KX-5 Twenty: $9950
The KX-5 Twenty line-level preamplifier enshrines almost all of the proprietary technologies that, in recent years, have put Ayre Acoustics on the map: Its Variable-Gain Transconductance (VGT) circuit adjusts volume not by throwing away varying amounts of gain but by adjusting, at its source, how much gain is created. Its active output buffer is based on Ayre's "diamond circuit" arrangement of bipolar transistors. And its AyreLock approach to voltage regulation creates, in essence, a push-pull power supply capable of turning on a dime in response to the demand dictated by the music signal. All of this is packaged in a non-huge aluminum enclosure described by AD as "tidy and evidently well laid out." Art was considerably less chipper about the KX-5 Twenty's user interface and owner's manual, for which he reserved such words as "unclear," "unneeded," "less than intuitive," and "both need work." He perked up again on hearing the Ayre's "remarkable and utterly nonclinical clarity, and its convincing, commandingly good spatial performance." Measurer-in-chief JA noted in particular the Ayre's "complete absence of power-supplyrelated" noise and its remarkably low distortion without reverting to loop negative feedback, declaring the KX-5 Twenty "superbly well engineered." In a Follow-Up, comparing the KX-5 Twenty with the similarly solid-state PS Audio BHK Signature, JCA noted the Ayre's drier sound and ability to "[carve] out a slightly deeper space," while giving the PS Audio pre the nod for controls and logistics. (Vol.41 Nos.3 & 6 WWW)

Ayre Acoustics KX-R Twenty: $29,950 ★
It would seem an impossible task: improving on a preamplifier—the Ayre KX-R—that sounded better to JA than no preamplifier at all. But that was the hurdle set for the new KX-R Twenty, named in honor of Ayre's 20th year of operation. More of a complete redesign than an upgrade of the original, the KX-R Twenty employs AyreLock, a new, proprietary approach to power-supply regulation that seems equal parts calculus and poetry. Also involved were similarly big changes to the active circuitry, including the adoption, in this model, of the "diamond" output circuit of the company's X-5 series—if only because, in the words of then chief engineer, the late Charles Hansen, it proved to work "so insanely well." Of his time with the new Ayre, JA wrote, "Some highly resolving audio components achieve their transparency to what has been captured on a recording by emphasizing detail. The Ayre simply cleaned the window." JA's listening notes were ripe with examples of fine performance at various sonic tasks, but in the end, his view was holistic: "The Ayre evoked the words Peter Schaffer has Antonio Salieri saying, in Amadeus, about the entry of the solo oboe in this music: 'This was a music I'd never heard. Filled with such longing, such unfulfillable longing. It seemed to me that I was hearing the voice of God.'" (Vol.37 No.12 WWW)

Benchmark LA-4: $2599 $$$
Benchmark's usual approach to design is to out-spec the competition, and so it is here. Like other Benchmark equipment he has tested, the affordable LA-4 challenged the resolution of JA's test instruments, with "superb" channel separation, "extremely low noise, and virtually no power-supply-related spuriae." Restricting his measurement to the audio band, JA found an "astonishing" S/N ratio of 105.5dB for both channels; it remained extremely low across the audioband. He summed up: "Benchmark's LA4 is the widest-bandwidth, widest-dynamic-range, lowest-noise, lowest-distortion preamplifier I have encountered." In his listening room, KR compared the LA-4 to a cable—and couldn't hear any difference. He concludes, "the LA4 is probably the most transparent and revealing audio component I've ever used. It does not seem to leave any fingerprints on the sound." (Vol.43. No.1 WWW)

Bespoke Audio Company Passive: $16,000 and up; $23,235 as reviewed ★
Built around a stereo pair of hand-wound, multi-tapped transformers, the Bespoke Audio preamplifier—which provides attenuation and source selection, but no gain—is a passive line stage that exudes an "unsurpassed" level of quality, according to AD. While declaring that he is not normally a fan of passive preamps, owing in particular to a paucity of musical impact in systems so equipped, AD noted that the Bespoke unit was better in that regard than he expected, and that its use brought enhanced clarity to some recordings; Bespoke Audio has, he believes, offered "the best justification yet" for the passive approach. In the June 2019 Stereophile, MF wrote of borrowing a version of the Bespoke passive pre with all-silver-wire transformers and Furutech Rhodium input and output XLRs ($23,235), praising its "black" backgrounds and declaring it "the most beautiful" high-end product of his experience. (Vol.38 No.10, Vol.42 No.6)

Boulder 2110: $59,000 ★
Given that its predecessor, the model 2010, enjoyed a 17-year run in Boulder Amplifiers' product line, much was expected of the new 2110 line preamplifier: a multibox solid-state model in which user functions are optically controlled to eliminate noise, and whose six inputs are characterized by an impressive degree of adjustability and flexibility of configuration. All of its inputs and outputs are fully balanced, addressed only with XLR jacks, and the 2110 goes the 2010 one better by adding a fully differentially balanced volume control. Using the Boulder 2110 with his darTZeel NHB-18NS mono amps in balanced mode, MF observed that "[it] produced image intensity, physicality, and solidity that were unprecedented in my experience. First take: a giant Wow." MF elaborated: "It made recordings I know to be truly exceptional sound even more so through my system." With the Boulder pre on his test bench, JA observed, "The 2110's distortion is so low, in fact, that it taxed my ability to measure it." JA ultimately pronounced the 2110 "the best-measuring preamplifier I have encountered." (Vol.38 No.3 WWW)

Bryston BP173: $4495 $$$
With its five single-ended inputs, two balanced inputs, and mix of single-ended and balanced outputs, the solid-state BP-173 is the middle model of Bryston's three line-level preamplifiers. It can be customized with a variety of add-ons, including a MM phono stage ($750), a DAC ($750), and a remote-control handset ($375). Used with a Mark Levinson No.534 power amp (see "Power Amplifiers"), a fully equipped BP-173 delighted LG with its ability to preserve bass weight and solidity when called for, and its no less impressive re-creation of recording-hall ambience. LG wrote that the Bryston "produced engaging, detailed, tonally captivating, utterly natural sound that approached reference quality," while noting, that matching with the correct amplifier is critical. JA's report from his lab on the "superbly well engineered" Bryston was similarly to the point: "It is difficult to see how a preamplifier could perform any better on the test bench!" Tests of phono and DAC modules also fared well. (Vol.41 No.6 Vol.42 Nos.6 & 7 WWW)

Convergent Audio Technology SL1 Renaissance Black Path Edition: $19,995 line only, $21,995 with phono stage
The Convergent Audio Technology SL1, which has grown a long name to match its long life, continues to be revised and refined by designer Ken Stevens. In its Renaissance update, the heralded CAT SL1 line stage received a new circuit-board layout and improved power supply; it was also treated to an A/V bypass, user-selectable gain, and a switch-selectable, moving-coil transformer for its optional phono stage ($2000). Compared to its predecessor, the SL1 Ultimate, the Renaissance offered greater transparency, resolution, and dynamics, said RD. JA noted "superb measured performance and an equally superbly linear circuit topology." The most recent (2015) change was occasioned by CAT's development of their Black Path signal capacitor, and named for it; further audio-circuit optimizations and a reduction in noise intermodulation are also among the refinements claimed for the Black Path Edition. After spending time with the SL1 Renaissance, RD pointed to improved rendering of intertransient silence, crisper and tighter percussion sounds, and better transparency and resolution than from the SL1 Ultimate: "I knew I was hearing no minor improvement." (Vol.32 No.11, Vol.38 No.12 WWW)

Dan D'Agostino Momentum HD: $40,000
The two-piece Momentum HD—its power supply is contained within its stand—is an all-balanced, fully discrete, line-level preamplifier with six inputs and two outputs, all via XLR connectors. As with the original Momentum, the HD's aesthetics keep pace with the designs of other D'Agostino creations: Here, the dial at the center of the front panel is a green-lit volume meter, its bezel the volume "knob." Once installed in JVS's system, the Momentum HD brought to a favorite recording of the Shostakovich Symphony No.11 "deeper and more resonant bass and an all-enveloping three-dimensional soundstage that was as thrilling as it was terrifying." He added, "with the Momentum HD, a new window opened, and every recording became a source of wonder." Writing from his test bench, JA noted that the Momentum HD fell slightly short of its predecessor in a few aspects of measured performance yet distinguished itself as "a well-engineered preamplifier." (Vol.43 No.2 WWW)

darTZeel NHB-18NS Mk.2: approx. $44,000
The "stunningly transparent" darTZeel NHB-18NS of 2007 offered spectacular transient speed, resolution, and decay, while providing an overall coherence that "made recorded music, analog or digital, sound much closer to live," according to MF, who added that, with its warm, vivid combination of red case and dark-gold front and rear panels, the NHB-18NS "looks like it sounds." As of the summer of 2008—by which time he'd bought one for himself—MF felt that the battery-powered NHB-18NS matched the resolution and transparency of MBL's 6010 D preamp, while managing to sound less mechanical. Despite the similar name, the NHB-18NS Mk.2 of 2017 is a complete redesign of the Swiss company's preamp but still offers both line and phono stages—the latter, per MF, being "sonically far superior to the original," and more adjustable than many outboard phono preamps of his experience. MF also hailed the new model's digitally displayed volume-control calibration, and the fact that, unlike that of its predecessor, the new model's batteries "have never run out of juice during a listening session." According to Mikey, the new darTZeel's phono section sounds "neither as transparent nor as dynamic" as the far more expensive outboard Swiss Precision P1 ($31,000 without additional power supply) or Ypsilon VPS-100 Silver Edition ($65,000). That said, with the "tube-like richness and generous flow" it inherited from its forebear, the Mk.2 "will more than satisfy casual vinyl listeners." (Vol.30 No.6, Vol.31 No.10, Vol.33 Nos. 5 & 10, Vol.40 No.6 WWW)

Lamm Industries L2.1 Reference: $27,990
The greatest accomplishments of Vladimir Lamm's electronics are like those of the art restorer who removes grime and soot without diminishing the vibrant colors beneath—so believes AD, who said of Lamm's latest line stage, the two-box L2.1 Reference, "[it] reproduced the sounds of bowed and plucked strings alike with color, texture, and humanness." The Lamm does so with an unorthodox combination of technologies: high-voltage MOSFETs in the all—single-ended gain stages; and tubes throughout its power supply, for rectification, regulation, and the amplification of voltage references. The L2.1 Reference, which differs from its predecessor in its use of new current-source transistors and other recently available components, offers switchable signal-phase inversion and easily adjusted channel balance—the latter thanks to its dual-mono volume potentiometers—and further delighted AD by eschewing remote control. His verdict: "the rare product that swept the question of tubes vs solid-state into insignificance." Writing from his test bench, JA noted the Lamm's "extraordinarily low" distortion and observed that, "like the other preamplifiers designed by Vladimir Lamm that have passed through my test lab, the L2.1 Reference is well engineered." In his Follow-Up, JVS noted that the L.2.1's presence in his system extracted the best from the Bricasti M15 stereo amp (see "Power Amplifiers"), writing that "the L2.1 did a bang-up job with percussion, restored the horns' natural bite and heat, and enhanced the three-dimensionality and musical intensity." In a different context and with a different recording, he acknowledged that the Lamm "toned down and softened a smidge" the natural edge on a singer's voice while adding, "That is not necessarily a bad thing." (Vol.40 No.7, Vol.41 No.7 WWW)

Mark Levinson No.526: $20,000
Pricewise, the No.526 occupies the slot between Mark Levinson's No.326S ($10,000) and No.52 ($30,000), and offers both line-level and MM/MC phono preamplification in a single box. The fully balanced No.526 also has an ESS Sabre-based 32-bit DAC with user-selectable PCM and DSD filter options—AES/EBU, S/PDIF, and USB inputs are provided—and a "digital-restoration" module that parent company Harman International calls Clari-Fi. In the manner of other contemporary microprocessor-enhanced preamps and integrated amps, individual inputs can be customized with the user's choice of names, gain offsets, etc., and provisions are offered for network connection (Ethernet) and firmware updates (USB). The No.526's "sheer clarity, startling transparency, [and] liquid midrange" impressed LG, who observed that the preamp's "qualities of design and manufacture let me be drawn into the music as never before." Writing from his test bench, JA said that, "Overall, the Mark Levinson No.526 offers superb measured performance." (Vol.40 No.5 WWW)

Pass Laboratories XP-22: $9500
The two-box, solid-state, line-level Pass XP-22 provides both balanced (XLR) and single-ended (RCA) inputs and outputs, plus a vestigial tape loop. The XP-22's volume control—an Avago-sourced encoder that JCA describes as having "good bearings and a nice feel"—is the same one used in Pass's upmarket XP-30, and balance is adjustable via a chunky metal handset that "duplicates all front-panel controls, and then some." JCA heard "impressive" bass impact, "pinpoint" imaging within a large soundstage (albeit one that shrank a little at lower volumes), and sound that "seemed a tad more open" than with his reference preamp. In measuring the XP-22, JA found "superb" channel separation, "extremely low noise," an "excellent" (85.35dB) audioband S/N ratio, and "extremely low" THD+N: "superb measured performance." (Vol.42 No.6 WWW)

Pass Laboratories XP-30: $16,500 ★
In its conventional two-channel mode, the XP-30 comprises three separate chassis: one each for its control circuitry and power supply and each channel's audio circuitry. Using additional chassis, the XP-30 can be expanded to as many as six channels. Each audio chassis has both a Master and a Slave analog output, duplicated on balanced XLRs and single-ended RCAs; and six analog inputs, also duplicated on balanced XLRs and single-ended RCAs. The XP-30 uses an integrated-circuit volume control. It virtually transported JA to recording studios and performance spaces, consistently drawing his attention to aspects of music rather than of sound. "The XP-30 has rekindled for me the concept that the beating heart of an audio system is the preamplifier," he said. Measured performance was superb. (Vol.36 No.4, Vol.38 No.5 WWW)

Placette Audio Active LineStage: $6995
The Active Linestage is intended to combine the transparency of Placette's purist Remote Volume Control with a usable level of functionality, providing five sets of unbalanced inputs, two sets of outputs, and a tape loop. Its absolute clarity, focus, solidity, and transparency were unrivaled in BD's experience. "Highly recommended." Sold direct, with a lifetime warranty and 30-day refund policy. (Vol.30 No.11 WWW)

PrimaLuna EVO 400: $4499
PrimaLuna's brand-new flagship line-level preamp—it replaces the company's DiaLogue Premium—the EVO 400 uses tubes for rectification as well as for gain and buffering, and includes input and output transformers that allow balanced operation. Noting that its extraordinary weight (52.8lb) comes not from its steel chassis but from its abundance of power-supply transformers and chokes, HR praised the EVO 400's very high parts quality and lavished similar praise on its "scintillating" presentation and ability to portray vivid, well-saturated musical colors while nevertheless being "more concise-sounding" than its predecessor in the PrimaLuna line. "It generated clearer, more muscular presentations with sharper focus and more distinctly punctuated momentums." Reporting from his test bench, JA noted that "the EVO 400 measures well for a tubed design." (Vol.42 No.7 WWW)

PS Audio BHK Signature Preamplifier: $5999 ★
Like its stablemate BHK Signature 300 monoblock amplifier, the BHK Signature preamplifier is named for its designer, Bascom H. King. Also like that monoblock, the BHK Signature preamp is a hybrid product, using both transistors (N-channel MOSFETs, also as in the BHK amp) and tubes (two 12AU7 dual-triodes, also put to work in the preamp's distinctive volume-control system, whereby some sound-level increments are achieved not through changes in resistance but through changes in tube-stage gain). Ten line-level inputs are divided evenly between single-ended (RCA) and balanced (XLR) jacks—there is no phono stage—as are the two outputs. Apart from noting that the above-mentioned volume-control system emitted an occasionally, barely perceptible noise that was ultimately masked by the music, JCA was impressed: after comparing the BHK Signature with nothing at all—that is, with the sound of a system in which a DAC drove a pair of PS Audio BHK Signature 300 monoblocks directly—JCA wrote: "With the BHK Signature preamplifier in the system, the music seemed more lively, and the space in which the images were cast was more tangible." Writing from his test bench, JA observed: "this preamplifier measured superbly." In his June 2018 Follow-Up, JCA compared the BHK Signature—now his reference—to the Ayre Acoustics KX-5 Twenty, noting that, by comparison, the PS Audio "softened . . . transients just a touch, slightly polishing the edges." But he found much to enjoy in both, and declared his BHK Signature "honest and musical." (Vol.40 No.6, Vol.41 No.6 WWW)

Rogue Audio RH-5: $2495 $$$
The Rogue RH-5 is a headphone amplifier and line-level preamplifier that offers three user-selectable levels of gain, and whose hybrid circuitry includes MOSFET transistors and two 12AU7 dual-triode tubes. It provides four line inputs—one balanced (XLR) and three single-ended (RCA)—as well as one set each of balanced and single-ended outputs, all on its rear panel. On its front panel are three headphone outputs: one three-pin XLR and two studio-grade sockets, each combining a three-pin XLR and a 1/2" phone jack. The Rogue allows two pairs of headphones to be used simultaneously. As a preamp, the RH-5 impressed HR with its "full-bodied sound," and did such a good job with Morphine's At Your Service that Herb was compelled to write, "I nearly drowned in this mesmerizing river—and for that I blame the Rogue RH-5's ability to submerge me in its every undercurrent and textured nuance." As a headphone amplifier, the Rogue "possessed the resolution, forcefulness, and transparency of a superior line stage," and excelled at driving low-sensitivity 'phones. HR noted that the RH-5's optional MC phono stage ($400) was "a super value" but lacked nuance in comparison with more expensive outboard phono preamps. Writing from his test bench, JA noted that the Rogue will perform its best with power amps whose input impedances are greater than 20k ohms, and concluded by describing the RH-5 as "a well-balanced design." (Vol.40 No.11 WWW)

Rogue Audio RP-7: $4995
This line-level preamplifier uses four 12AU7 dual-triode tubes and contains 17 (!) separate power supplies, including an individual regulated filament supply for each tube. Its military-spec circuit board is endowed with heavy copper traces and graced with an abundance of Vishay HEXFRED diodes, Vishay resistors, and Mundorf oil-caps. The Rogue's rear panel is itself abundant with connectors: three unbalanced (RCA) line-level inputs, two balanced (XLR) line-level inputs, and two each unbalanced and balanced outputs, following the same connector conventions. The front panel is notable for more than just its single 1/4" headphone jack and its old-school volume knob: It also includes a Balance knob, which HR loved. Used in conjunction with HR's First Watt SIT-3 solid-state amplifier, the Rogue preamp delivered "a superbly balanced and invigorating—nay, intoxicating—system that didn't sound like tubes or solid-state. But it did reproduce, with extraordinary weight and saturated tones, my latest favorite piano album." Herb's conclusion: "My new reference." In measuring the RP-7, JA found that, "as long as it's driving a power amplifier with a high input impedance, Rogue's RP-7 offers generally respectable measured performance." (Vol.42 No.3 WWW)

Sugden Masterclass LA-4: $3750
Sugden's solid-state, line-level-only Masterclass LA-4 offers four single-ended (RCA) inputs and one balanced (XLR) input, with outputs of both of those types. (The circuitry is fully balanced overall.) Gain is generous—JA would measure ca 20dB, single-ended or balanced—with signal attenuation courtesy of an old-school volume control. With the Sugden in his system, JCA noted "more ambiance with good recordings" than through his reference PS Audio preamp, but also "a touch less body." Overall, the Masterclass LA-4 "subtly illuminated the music," and "preserved subtle soundstage cues." JA's measurements uncovered lower-than-specified output impedance, thus indicating good compatibility with a variety of power amps, but a "disappointing" wideband S/N ratio. (Vol.42 No.4 WWW)

VAC Signature SE: $19,500 (line stage only), $26,000 (with phono) ★
In its basic form, the Signature SE ($19,500) is a tubed line stage that offers a mix of balanced (XLR) and unbalanced (RCA) inputs and outputs, the latter addressed by custom-designed output transformers. Its optional phono stage ($6500)—dual-triode tubes, MC step-up transformers, separate power-supply transformer, and all—fits alongside the line-level circuitry in the preamp's main enclosure. (A second, separate chassis is devoted to the line stage's power supply.) In his last review for Stereophile, our beloved friend BJR described the VAC Signature SE as nothing less than "the most significant audio product I've ever hooked up to my reference system. It was flawless." Noting, in his measurements, some frequency-dependent "poor overload margin" and "high intermodulation distortion" in the VAC's phono stage, JA recommended partnering the preamp only with phono cartridges of lower-than-average output. (Vol.38 No.6 WWW)

VTL TL6.5 Series II Signature: $18,000
Essentially a single-box version of VTL's TL7.5, the fully balanced TL6.5 Series II Signature line-level preamplifier combines a gain stage based on vacuum tubes—one 12AU7 per channel—with an output stage using solid-state devices. For the Series II version, those devices have been upgraded from MOSFETs to an unidentified type of FET that VTL says is more tube-like in its behavior. Other technical changes include the elimination of global feedback and a doubling-up of mains transformers. FK described the TL6.5 Series II Signature as "the smoothest-sounding preamp I've heard in my system—and I don't mean smooth in a pejorative sense." He also described extended trebles that were "pure" and "natural," abundant speed and consequent added realism on percussive sounds, and good imaging "without excessive beam." JA's measurements confirmed the VTL's high quality: "The TL6.5 Series II Signature is a well-engineered preamplifier—as I have come to expect from VTL." (Vol.39 No.8 WWW)

Ypsilon PST-100 Mk.2: $37,000 ★
Made in Greece, the PST-100 is a handsome tubed preamplifier housed in a thick, satin-finished aluminum chassis. It features transformer-based attenuation, 6CA4 tube rectification, choke supply filtering, a switchable passive mode, and a zero-feedback active stage based on a carefully selected Siemens C3m pentode tube. Though differences between the PST-100's active and passive stages were small, MF preferred the passive stage for its purer, more transparent sound. Compared to the darTZeel NHB-18NS, the Ypsilon produced more vivid tonal colors and greater physicality. "For now," MF concluded, "the Ypsilon PST-100 is the most transparent and, therefore, the most perfect audio component I have ever heard—or not heard." Though XLR input and output jacks are provided, the circuitry is unbalanced only. Without a line stage, the completely passive PST-100 TA costs $26,000. (Vol.34 No.7 WWW)

B

Audia Flight FLS1: $6995
The made-in-Italy FLS1 is a solid-state line-level preamplifier with a fully balanced architecture—both single-ended (RCA) and balanced (XLR) inputs and outputs are provided—and a built-in headphone amplifier. Extra-cost options include a phono-preamp board with MM and MC inputs and adjustable loading ($1000) and a DSD-friendly DAC board ($2000), the latter of which was unavailable at the time of our review; both are user-installable. All of the FLS1's user interfaces are microprocessor controlled, with the aid of an OLED screen and a system of nested menus; all were described as "elegant" and "easy" by reviewer MF, who also noted that "the feature-packed FLS1 doesn't look, feel, or sound as if Audia Flight has compromised on quality," and described the sound on both line and phono inputs as leaning "somewhat toward the warm, midrange-rich side." In measuring the Audia Flight pre, JA found "superbly low" RIAA error, and concluded that, "overall, Audia Flight's FLS1 offered simply superb measured performance." Phono card adds $1000; DAC card $2000. (Vol.42 No.4 WWW)

PrimaLuna ProLogue Premium: $2199
PrimaLuna, a company that has been linked to a recent worldwide shortage of uppercase letters, designed this old-school, line-level tubed preamp in the Netherlands and builds it in China to "levels of quiet, durability, and sonic sophistication not possible in the 20th century," according to HR. The tube complement comprises four 12AU7 dual-triodes and a dual-mono pair of 5AR4 rectifiers, the latter an unusual choice in an era when so many preamp manufacturers economize by using solid-state rectifiers. Five single-ended inputs are offered, alongside two single-ended outputs and a tape out; a remote handset is supplied to control the ProLogue Premium's motorized Alps volume control, if desired. Used in a system that included, at times, PrimaLuna's ProLogue Premium power amplifier (built into an identical blue-gray steel enclosure), the ProLogue Premium preamp impressed HR with its "feminine and seductive" sound. While cautioning readers that the PrimaLuna's high (2800 ohms) output impedance demands a partnering amplifier with an input impedance not lower than 28k ohms, Herb observed that the owner of a properly set up ProLogue Premium preamp will enjoy "tangibly luminous presence in every recording you play. Punch and drive should be obvious. . . . Most of all, you should notice [its] liquid transparency." JA reported that the ProLogue Premium preamp "generally measures well," but he did discover a second-harmonic distortion signature that could be counted on to "fatten up the sound." (Vol.40 No.6 WWW)

Editor's Note: There are currently no Class C & D preamplifiers listed.

K

Luxman CL-1000.

Deletions
Rogue RP-1, not auditioned in a long time.

COMMENTS
Bogolu Haranath's picture

Time for Stereophile to review the Denafrips flagship Terminator DAC (under $5k) :-) ........

Kempff's picture

Audioquest Nightowl Carbon (and its Nighthawk sibling) have been discontinued.

There's a new version of the Chord Mojo? Do you know something no one else does?

Bogolu Haranath's picture

AQ NightOwl Carbon is listed under Class-B headphones :-) .......

Kempff's picture

That’s my point. Discontinued items aren’t supposed to be listed.

Bogolu Haranath's picture

May be the people who worked on the list are dis-connected :-) ........

Jim Austin's picture

When we contacted companies about changes in their product lines, as we do before every Recommended Components issue, we were told by AudioQuest that the NightHawk and the NightOwl were still current products.

As for the Mojo, the reason given for its deletion from the list is in error--my error. It is the Hugo, not the Mojo, that has been replaced. The Mojo was deleted because it was last auditioned by a Stereophile writer in the February issue, 2016. Unless awarded a star, components typically "age out" after about three years.

Jim Austin, Editor
Stereophile

Kempff's picture

I guess one hand doesn't know what the other is doing at AQ. They sent out a letter to dealers over a year ago announcing that they were "leaving the headphone category," and they stopped producing the nightbirds at that time. But their website still features them as if they're current.

I'm not sure I understand about the Mojo, though. There are quite a few things on the RC list that were reviewed before the Mojo and don't have stars -- the Audeze LCD-X and Senn HD-650, to pick a couple from the same page. Besides, the Mojo surely deserves a star if anything does: it's a classic, sounds fantastic, and has no competition at its price point. It was the RC listing and JA's review that convinced me to take the plunge, and I've loved it ever since.

Jim Austin's picture

Thanks for your note. Well, the HD-650 should have a star, and I'm going to give it one; there aren't many headphones (HD-600 to name one) that have been around as long and still perform well. In any case, I own a pair, and I think JA1 does, too. As you can read in the intro to the section, we keep things on the list if a reviewer has recent experience and still finds the product worthy. The LCD-X is an example of that: JA owns a pair and uses them often.

That's the general case: Products that were reviewed longer ago than the Mojo but still on the list are there because they are in some reviewer's system.

I've never heard the Mojo, but based on its reputation, I certainly respect it. Whether it's a "classic" is of course a judgment call; smart people can disagree.

Best Wishes,

Jim Austin, Editor
Stereophile

tonykaz's picture

to "excellent" ?

Are some reviewers assigning the Excellent designation but not quite meaning it unless the "truly" adverb precedes the critical adjective? Is this a "secret" writers code word for some reason ?

Why do people feel the need to crutch support their declarations with clumsy adverbs?, seems like it dilutes the most important concepts and fosters mistrust of the Writers intentions.

Those dam Brits have taken to say'n "to be honest" or "if I'm honest" . ( We don't see it here, thank you. )
Feels like the Brit leading off with "If I'm honest" is someone I shouldn't be listening to. ( especially if it's coming from a Religious Minister that buys a series of my Sunday performance Sermons ).

My Audio Importing, Manufacturing & Retailing experiences reveal these Recommended Component Issues to have critical influence in the buying decisions of Audiophiles. Your gifted "fiancé of audio adventures" ( Mr.HR ) is probably the most influential man of letters in this here entire Industry. Mr.Steve G. is souring into Cassey Neistat territory with his Audio related YouTube dailies, big hair & colorful shirts. ( he only needs an electric scooter to ride the now-Empty Streets of Manhattan ) The NEW Steve G. is makning 33.3 look like its soooooo Old-School tired. Of course, I approve.

Tony in Venice

Tony in Sunny Venice

ps .. by the way, Audiologists are still using Astell & Kern players.

Bogolu Haranath's picture

To be honest, I think these recommended component lists are very excellent :-) .......

Bogolu Haranath's picture

BTW ....... Tom Brady is gonna play in a town near you :-) .......

tonykaz's picture

and...

Who cares ?

Tony in Venice

Bogolu Haranath's picture

You don't know the record holder, 6 times Super Bowl winner? :-) .......

tonykaz's picture

I have a super bowl that holds 5 cups of cereal.

Tony in Venice

ps. I'm probably not a proper American

Tromatic's picture

Oddly enough I can believe someone who praises the Chinese government does not know who Brady is, although I do agree with "who cares".

tonykaz's picture

Who? I don't know anyone like this .

Tony in Venice

Tromatic's picture

In one of your voluminous screeds about how racist the US is if IRC.
I was going to post something about how the typical Uighur would disagree with you but that would have been off-topic. I'll look for it if you wish, but it may take some time.

I can see how you would forget.

tonykaz's picture

You might have the wrong fellow. I'm contending that China has been an Industrial Quality Leader for the last 5 Centuries ( with the recent decades being the exception )

I do not approve of my GMCorp. going to Asia to take free Labor while abandoning our local legacy Labor.

What is IRC ?

Graham Luke's picture

We must wean ourselves off this curse.
Well, we wouldn't buy stuff from Kim Jong Un so why are we buying it from the PRC....?

misterc59's picture

Sorry, don't know how this ended up under this comment, plus the body of my post went AWOL. I think I'll wait until the posting gods have (hopefully) fixed the problem...

Bogolu Haranath's picture

$400 Project Pre Box S2 is listed in Class-A digital processors ........ To be honest, I think that is very excellent :-) ........

Indydan's picture

To be honest. You should listen to more music, and post less.

tonykaz's picture

"to be honest" is the actual writer saying that he is not normally an honest reporter.

So, I ask, are you being facetious ? I think yes as your comments are typically concise.

Tony in Venice

ps. I'm not here for Music, I'm here for the Literary ( editorial ) Content. I can select Audio Gear without reviewer guidance. I have an Audiologist & Psychiatrist to help me synchronize my personal hearing curves, tastes and synapse tunings. I seem to prefer Class A and still haven't been able to tune-in Class D amplification as satisfactorily as the Norther Europeans have achieved.

Ortofan's picture

... the Pro-Ject Amp Box RS, which combines Hypex class D power amp modules with a vacuum tube input buffer stage.
You could buy one with your $1,200 UBI and still have some change left over.
It's even available at those Best Buy stores with a Magnolia department.

https://www.pro-jectusa.com/en-us/products/pro-ject-box-designs/amplifiers/rs-line/amp-box-rs

Bogolu Haranath's picture

HR could review the Amp Box RS :-) ........

tonykaz's picture

I can't thank you.

Of course you proffer dam good advice, as usual.

I'm something of a Maverick Brand Ambassador for Schiit & PS Audio ( although either Company would & should say that I'm strictly out-on-my-own and not part of their operations ) I think that Mr.s Stoddard and McGowan are both men of high integrity ( maybe even including M.Moffat who might be a horrible smart ass and proud of it )

I was once a Dealer for PS Audio ( 1980s ) and Tyll introduced me to Schiit back in 2011. Both outfits manufacture in the USA, service their products, answer customers, make A+ level products and price sensibly. What's not to like except for Schiit's dam Name and their stupid rear mounted power switches.

As far as those UBIs are concerned, the Corporate worshiping donkeys may not allow we civilians the same life saving financial treatment being lavished on their sponsoring donor Class. Boeing to accept $60 Billion after ruining their financials with the 787 and 737 mismanagements.

Fingers crossed on those $1,200 ea. with $5,000 per family, I'll be investing in Color changing LED Lighting.

Tony in Venice

Ortofan's picture

... Maverick Brand Ambassador for Schiit Audio - and since Messrs. Stoddard and Moffat seem to know their way around tubes, as well as transistors - perhaps you could suggest to them that they design a variation of the Vidar power amp with a vacuum tube front end. It could effectively be a budget version of the PS Audio BHK amp.

tonykaz's picture

I'm certain that Mr.Stoddard would entertain your own personal inquiry far more than they would value my nudging suggestions which typically get tossed ( like my standard insistant demand for ALLLLL dam power switching be located on the dam FRONT panel AND! Dammit, change the Brand Name to Stoddard & Moffat like any respectable Company would normally do!!!

I love your idea for Product Development Improvements. ( go ahead and nominate yourself to Schiit's advisory board, I'll second it)

Are you sure about Moffat and tubes ? I wonder if he's cooking up a nice tube DAC?

Tony in Venice

tonykaz's picture

I'm certain that Mr.Stoddard would entertain your own personal inquiry far more than they would value my nudging suggestions which typically get tossed ( like my standard insistant demand for ALLLLL dam power switching be located on the dam FRONT panel AND! Dammit, change the Brand Name to Stoddard & Moffat like any respectable Company would normally do!!!

I love your idea for Product Development Improvements. ( go ahead and nominate yourself to Schiit's advisory board, I'll second it)

Are you sure about Moffat and tubes ? I wonder if he's cooking up a nice tube DAC?

Tony in Venice

Bogolu Haranath's picture

Your idea of a tube DAC is a smart idea for S. Audio ........ They could offer that DAC with a choice of tube or transistor output ......... They could also offer a choice of multiple digital reconstruction filters for that DAC :-) ........

tonykaz's picture

Why does it need multiple reconstruction?

I suspect that we are already past the point where DACs feature discernible sound quality differences, although professionals like Bob Katz carefully choose converters and can hear details beyond "normal" amateur listeners.

But...

... for the sake of outlandish Pricing, Schiit could offer a DAC made up of ONLY Tubes, much like the very first IBM Computer needing a very large room. Price it at, say..., 3 Million Dollars. Lets give em sumpt'n to talk about.

Tony in Venice

Bogolu Haranath's picture

*

tonykaz's picture

...

Bogolu Haranath's picture

*

tonykaz's picture

...

Bogolu Haranath's picture

Almost all of the DACs which offer multiple filters, also offer the standard linear phase 'brick-wall' filter ...... Some listeners choose other types of filters because, they say that, those filters sound more 'analog like' .......... Those other filters are available with a push of a button ....... Similarly, tube or transistor output could be chosen with a push of a button :-) .........

Bogolu Haranath's picture

When Mr.Tony and Mr.Ortofan become the board members of S. Audio, they could make the suggestion about the above mentioned tube DAC :-) .......

tonykaz's picture

Sir Ortofan is leagues beyond me in logical expressions, I would never be welcomed to that exclusive Board of Directors ( BOD ).

Can Orto fandom be explained?

Tony in Venice

tonykaz's picture

Sir Ortofan is leagues beyond me in logical expressions, I would never be welcomed to that exclusive Board of Directors ( BOD ).

Can Orto fandom be explained?

Tony in Venice

Bogolu Haranath's picture

Mr.Ortofan got a 'face tat' which says 'I got the power' :-) ........

Bogolu Haranath's picture

Or ..... May be the tattoo says 'Better at 70' :-) .......

Bogolu Haranath's picture

Mr.Indydan ........ To be honest, you should listen to more music and read less posts or, better yet, read no posts at all :-) .......

tonykaz's picture

looks like a $1,200 UBI per person with a married cap ( possibly $2,500 )

Tony in Venice

enrique majluf's picture

Dear Misters. of Stereophile, it seems to me that they have made a mistake in removing the DAC Bryston from the list, since Larry Greenhill has them within his teams for his reviews, as well as other components of Bryston. His last review was on February 27, 2020. You can't say you haven't been auditioned in a long time.

jay.levine's picture

Just curious how that decision is made? I have a VTA 120 from Bob Latino and it too can be purchased fully assembled--great amp for the money (along with his mono-blocks)--surely they along with a couple of other similar amps deserve attention.

davemill's picture

I am wondering why the B&W 702 S2 are considered “Full Range” while their specifications don’t go to 20 Hz. Stereophile’s review measurements also don’t support this categorization. If these really aren’t “Restricted Extreme LF”, the same should apply to the Revel Performa F228Be.

davemill's picture

I am wondering why the B&W 702 S2 are considered “Full Range” while their specifications don’t go to 20 Hz. Stereophile’s review measurements also don’t support this categorization. If these really aren’t “Restricted Extreme LF”, the same should apply to the Revel Performa F228Be. Perhaps this rule only applies to Class A, I may have just answered my own question. This seems arbitrary to even have Restricted Extreme LF categorization for the other classes unless there are different requirements for them?.

brams's picture

It is not very clear (at least to me) how items rated in one class are subjectively considered to be superior performers to those in the class below. To clarify this it would be helpful in each case to include a small blurb in the comments for each item not considered to be in class A as to why they were not included in the class above. For example the comment for an item in class B would say " Misses class A because in all systems tested it lacked the ultimate resolution of the lowest ranked item currently considered to be in class A" or "Is slightly too sweet or bright to be considered neutral".

In some cases the reasoning can be gleaned by careful reading of the reviews (and perhaps that is Stereophile's intent), but in many cases it is simply not clear.

As a case in point, consider the case of the Kef Reference 5. It is rated as class B while the LS50 is rated as class A LF. However a reading of the Reference 5 review specifically with comparison to other speakers (eg. Magico) currently listed as class A provides no clue to the reason for the ranking especially relative to the ranking of the LS50. Yes, the Reference 5 appears to be slightly sweeter than other class A speakers, but we are also told that its high end performance is similar to the class A Magico.

Now I have heard both the LS50 and Reference 5 in various systems. I also own the little brother to the Reference 5, the Reference 1. It is my opinion that there is no sane person who after hearing all three who could realistically make the case that the LS50 is anywhere near the performance of either Reference speaker. This opinion appears to be supported by any objective testing I have seen. How then does Stereophile explain this discrepancy?

Stereophile owes it to its readers to explain such anomalies as it risks casting doubt on the legitimacy of the Recommended Components list. Perhaps there is a valid reason in the example provided. If so, I would like to hear it. Your general comments in the "How We Do It" section does not appear to cover this.

Alan Marcy's picture

Hi! Stirful & other text addicts. I wandered into good sound visiting a surviving friend who ran off to Paris, France after he got his PHD at the University of Minnesota to teach Romance Languages at the Sorbonne. We are both offline (Text-talk for too old for anyone to care that he is now (Class
D) a dread illegal alien in France) after running Sorbonne until they demanded he retire. He has since married his lover in this US of A, is free of her homeland, China. They had visited her family in China and were happy to get their marriage approved. Families are perhaps as picky as loyal readers of this fine publication, even online.I HAVE UTFERED
i have ordered, om the comments om Vlass===]]]

ckassf Vkass S,

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