When I was a teenager growing up in South Los Angeles in the 1960s, the most vaunted among us were the guys who tinkered with their cars and souped them up with fuel injection, overhead cams, dual carburetors, heavy-duty MacPherson strut suspensions, and 8-track super stereos with speakers arrayed in the dash, the doors, and the rear deck under a tinted back window. This was the SoCal car culture celebrated by the Beach Boys in “Little Deuce Coupe,” “Fun, Fun, Fun,” and “Don’t Worry Baby” -- male-teen sexual prowess sublimated and distilled into small fleets of superb, gleaming machines and gallant jalopies. A guy I knew in my neighborhood was always under the hood of his ’50s Dodge coupe, working some sort of magic I had no clue about. His father and uncles were partners in a gas station and garage, and my friend had been a grease monkey since childhood, at first just pumping gas and changing tires and spark plugs, but quickly advancing until he could swap out stock parts for custom, fine-tune an engine’s timing, raise a car’s suspension, and supercharge everything in his inline six engine until it could accelerate faster than a stock V8. He was a marvel among us and his wheels were so cool, he got all the girls we could only dream of dating.

I’d venture to say that Kevin Hayes is no ladies’ man, but he, too, grew up tinkering -- not with cars but with audio gear. He told me he caught the bug from his father, who’d gotten an idea for a hi-fi amp in 1944 while in the US Navy and even drew up blueprints for it after he left the service, coming back with new skills and interests, like so many veterans of WWII. In audio electronics -- a quieter, much less desperate pursuit than hot-rodding -- Hayes found his own brand of cool. When I spoke to him recently, he told me about his Spider-Man moment.

“My father had a Heathkit system he’d built -- my first hi-fi. When I was four or five, I burned my fingers on a tube, and I think that’s how I got bit by the bug. By eight or nine, I’d started playing around with audio equipment on my own. Then, by my late teens, I was making measurements on an oscilloscope, comparing total harmonic distortion in Mac and Citation amps, channel separation, etc. It was a mucky era, fooling around with Audio Research, Meitner, Harman/Kardon stuff. By my mid teens, I was studying the Radiotron Designer’s Handbook and wondering why a 30W Heathkit tube amp sounded better than a 200W Lafayette solid-state receiver I’d just spent all my lawn-mowing money on.”


Since then, Hayes has not only founded the Valve Amplification Company, but created several generations of preamplifiers and power amplifiers, perhaps culminating in VAC’s Statement preamp, a cost-no-object marvel of invention -- $80,000 USD each for its line stage and standalone phono stage -- at the pinnacle of vacuum-tube electronics technology. Recently, Hayes applied discoveries and improvements he’d made in developing the Statement to VAC’s Master preamp -- still expensive, if at least theoretically affordable for those of us who live in the real world: $28,000 (line stage only) or $40,000 (with moving-magnet/moving-coil phono stage). From VAC’s product brochure: “If the Statement products might be likened to Formula 1 race cars, the Master Preamplifier is the derivative ultra-performance road-going sports car.”

Background and development

Kevin Hayes told me that his goal for the Master preamp was to take the basic technology of the Statement and “marry it to the legacy chassis” of his earlier preamps, distilling it to its most essential form within a two-box enclosure. These essential elements were: 1) an ultra level of decoupling technology to isolate the tubes and resistors from mechanical vibrations; 2) the use of Z-foil passive resistors throughout; 3) an elaborate, motorized, 4.84-pound brass volume control to be used with a proprietary remote control; and 4) exotic capacitors, some made of beeswax, in the phono stage’s RIAA network.

Rather than years or even a year, this took Hayes mere months. “The process wasn’t particularly difficult,” he said. The basic circuit designs were similar. He’d already developed the isolation and drive systems for the Statement’s Alps-sourced volume control; creating the Master was only a matter of fitting the other improvements onto a chassis and into a case of different size and shape. He used hand-wired class-A1 audio circuits carried on machined, mass-loading plates entirely decoupled from the main chassis. He used the same “naked” Z-foil resistors and premium transformers as in the Statement line stage. “It went from 25¢ resistors in the Signature SE to $10 resistors in the Master,” he said, chuckling.

The Master phono stage followed a similar path but involved a bit more work. Here Hayes followed the same principles of isolation as he had in the Statement, using the same plating materials, wire shielding, and decoupling mechanisms to solidify detail while reducing microphony. All technology regarding resistors and capacitors and much of it regarding decoupling remained the same.

Although the less expensive Signature Mk.IIa SE preamplifier ($19,990, line stage only; add $6500 for phono stage) contains the same basic circuit topology as the Master, the latter represents far more obsessive treatment of the power supply, and the layout of the Master phono stage’s circuit is copied from the Statement. This includes point-to-point wiring, a twin triode tube complement, a passive RIAA circuit that uses no feedback, and, for gain, an amorphous-core transformer made by Lundahl. Many of the other parts are custom-made -- some cost 100 times more than their counterparts in the Signature. Yet, like the Signature, the Master has separate power supplies for linestage and phono within the same box, ensuring complete isolation between them. For all intents, both the Master and Signature phonos are external phono stages that just happen to share the same chassis as the linestage.

Description and setup

The Master’s control circuitry comes in an enclosure with only one choice of finish: powder-coated in black with knobs (there are no pushbuttons) plated in hard-chromed silver (add $100 for gold). The faceplate is available in standard black or silver (add $400). My very handsome review unit came fitted with built-in MM/MC phono and had a black faceplate with silver knobs on the control unit and a black faceplate (silver available) on the power supply. Double, black-jacketed umbilicals (separate ones for linestage and phono) with beefy, ring-tightened aluminum connectors joined the two-box unit together.

Along with its stock power cord and full complement of signal tubes (two 6922 tubes in the line stage, six 12AX7 tubes in the phono stage), the Master comes with a remote-control handset of metal that has a cutout for a handsome aluminum top plate with volume up and down controls and a mute button. There is also a very detailed, 14-page user’s manual that includes guidance for the installation and replacement of tubes.

The Master came in a large, layered container in which the power supply was separated from the control unit with sheets and molded blocks of Styrofoam. Each enclosure was bagged in thick plastic and taped shut, its faceplate wrapped in khaki-colored cloth secured with rubber bands. The remote was bubble-wrapped in a tidy sleeve and nestled in its own cutout in the foam.

The control box measures 18”W x 5.5”H x 14.5”D. Centered on its faceplate is an attractive cutout window with a dimmable LED display, the VAC logo glowing butane blue. Under it is a pinhole light that glows red when the power is on. Immediately to left and right of the display are two large knobs for, respectively, input selection and volume control. At far left and right are pairs of smaller knobs: at left, Logo and Mute; at right, Cinema Bypass and Power.

The slightly smaller (18”W x 4.3”H x 14.5”D) but much heavier (transformers!) power supply sports a similar look, but on its faceplate is only the illuminated cutout displaying the VAC logo. The combined weight of the control and power-supply boxes is about 62 pounds, but I found them easy to lift and carry around separately. I placed the control box on the third shelf of my Box audio rack and the power supply in an adjacent Pottery Barn console, linked with the generously long umbilicals.


On the control box’s rear panel sprout many connectors. Besides Cinema Bypass, the line-stage section of this panel has five sets of input connectors (six if phono is not fitted), two of them with both unbalanced (RCA) and balanced (XLR) connectors. The phono panel also has both types for MC connections and unbalanced RCAs for MM. Each pair of dual-option connections has a toggle switch to select between unbalanced and balanced operation; the two outputs also have such dual connectors and toggles. Finally, on the phono section of the rear panel are a grounding pin and switches for selecting between MC and MM and for loading MCs (470, 300, 250, 200, 150, 100 ohms). On the back of the power supply is an IEC inlet for the stock power cord.

The interior of the Master’s control unit is discretely divided: the line stage occupies the two-thirds of the space from center left to far right, and the phono stage fills up the left portion. The line stage uses two 8416 twin-triode tubes (acceptable substitutes: 7308, 6922, E88CC, ECC88, 6DJ8, 12DJ8). The Master’s specified gain is 12dB, with an output impedance of less than 150 ohms (20Hz-20kHz); the recommended output load is a minimum of 300 ohms, and the Master doesn’t invert absolute phase. Its specified frequency response and total harmonic distortion of <0.009% at 1kHz, 1V RMS are impressive. The phono-stage gains are 44dB (MM) and 64dB (MC). Inside the case, these circuits sit like glittering jewel boxes of decoupling.

I used the Master’s balanced outputs to connect it to two different stereo power amplifiers -- VAC’s own 200iQ and a Zanden 8120. I also used one set of balanced inputs for connection to my Esoteric K-05x SACD player. I ditched the Master’s stock power cord and instead used an Audience SX cord plugged into an Audience aR6-TSSOX line conditioner that in turn was plugged into an Oyaide R1 duplex wall outlet with a second Audience SX. The system was on its own dedicated line.

Listening and operation

Kevin Hayes had told me that the amorphous-core transformer in the VAC Master’s phono stage would need at least 250 hours of run-in before its sound stabilized, so I put in over 300 hours on it before taking any listening notes. Meanwhile, I didn’t suffer much -- the Master sounded decent right out of the box, though the phono stage did lag behind the line stage in finding its full robustness and dynamic capability.

As for gain, I never had to turn the Master’s volume control past 11 o’clock to rock my room hard. For most of my listening, I set it between 9 and 10:30. The line stage’s 12dB of gain proved reasonable and about midway between two other line stages I’ve had in my system -- the Zanden 3100 (9dB) and Lamm LL2.1 (18dB) -- and far below the whopping 22dB of the VAC Renaissance Mk.3, which I reviewed.

One of the first recordings that showed what the Master could do was the late Roy Hargrove’s Earfood (CD, Verve 0010997-02), recorded with his quintet. “I’m Not So Sure” abounded with impressive dynamics and sound pressure. Montez Coleman’s tom thwacks, snare thonks, and rim shots all came in perfect time, blessed with transient puffs of pressure I could almost see. In his solo, Hargrove’s trumpet sounded fresh, brassy, and blatty, and Justin Robinson’s alto-sax solo was plaintive and straight-ahead, then scrambling and syncopated as it progressed. Their doubled choruses were full of punch and swagger, and all six minutes of this track comprised a pleasingly rhythmic experience reminiscent of more accessible work by Hugh Masekela and Ramsey Lewis. The entire CD had a plush yet punchy sound full of liveliness and intense pulse.

Likewise, the recent remastering of the Band’s pre-roots-rock classic of 1968, Music from Big Pink (CD, Capitol B0028422-02), sounded extraordinary -- full of flavorful vocal textures, tactile guitar work, and remarkable definition of instruments. “Tears of Rage” still had that famous spookiness around Richard Manuel’s verge-of-falsetto lead vocal against the main soundfield of Garth Hudson’s swirling Hammond organ and Rick Danko’s rumbling bass, variously penetrated by a gently chattering tambourine, Danko’s moaning harmonies, and squeals and peals from Robbie Robertson’s Telecaster. Levon Helm’s drums punched and thunked with a swampy flavor. Centerfill was strong, and the music reached forward from between the speakers into my listening room. A wide, deep musical tapestry was woven of the various threads of gorgeous instrumental and vocal sound. It all made clear how brilliant this arrangement and their musicianship were half a century ago, when these five guys picked up this entire broken country of ours and let us all weep and dance in our souls.

With baroque music, the Master proved no less capable, rendering, with complete authority, Florilegium’s version of Bach’s Brandenberg Concerto No.3 in C Major (Brandenberg Concertos, Channel Classics CSS SA 35914 SACD) and its rapid, energetic bowings on string instruments and insane difficulties of timing. Violins were sweet and sprightly, violas and violas da gamba admirably filled out the sound, and the entire performance sounded grave and sonorous, offering a depth of sound that was complete from top to bottom, with harmonic sparkle, perfect timing, and great verve. There was no haze, glossiness, or edge in the strings, which sounded continuously open and not so much warm as full. It was easy to get grabbed up in the feeling of Florilegium building this work’s tension and momentum, its penetrating pulse and dimensional layers.


I loved the way the Master reproduced women’s voices. Renée Fleming sings “Endless pleasure, endless love,” from Handel’s Semele, on the recital disc Handel (CD, Decca B0002SZVV8), a recording that features her distinctively pure, creamy soprano. This saucy aria is taken allegro, Fleming accompanied by the Orchestra of the Age of Enlightenment, a chamber ensemble that performs these intricate baroque scores under the precise direction of Harry Bicket. Fleming sounded agile and sprightly at the top of her range and chesty and pleasantly darker in her lower notes, which made for contrasts not only in register but in texture and timbre. The soundfield was beautifully interwoven with voice and instruments, including the occasional light touches of a harp. I could also feel the viola da gamba gently pressurizing the room as Fleming trilled and thrilled gorgeously, her voice shimmering in shallow sonic waves across the room as though a pale, translucent scarf were trailing behind her as she sang.

Bill Evans’s piano playing has been a staple of my listening since I first discovered him, as most of us did, on Miles Davis’s Kind of Blue (1959) when I was a college freshman in 1969. I think I’ve collected just about all of his readily available recordings, on both CD and LP, and his Waltz for Debby, also from 1959 (Riverside/Analogue Productions APJ 009), is still one of my favorites. I listened to “My Foolish Heart,” and there again, immediately, was that recognizable harmonic richness, Evans’s notes solid, emphatic, full of presence. I’ve listened to this recording scores, if not hundreds of times, but the VAC Master’s reproduction of it made Evans’s piano, Scott LaFaro’s double bass, and Paul Motian’s drums sound richer than ever, the piano’s ringing notes reaching into the room like the gigantic paws of a plush tiger.

Speaking of plush textures, when I spun k.d. lang’s Ingénue: 25th Anniversary Edition (LP, Nonesuch 559289-1), I was swaddled in vocal velvet. The singer’s aching, airy voice in “Save Me,” close-miked and full of affective portamento just killed me. The soundfield around her was a bounty of percussion, a shimmering bassline, an electric guitar sometimes strummed and at times sensitively plucked, a pedal steel providing a sonic backdrop along with the tease of a female chorus cooing along with it. Here and there, as though for atmosphere, light notes from an acoustic guitar made sounds like a cymbalom, and the entire track throbbed, gorgeously fat with sexuality and the heroin-hazed aftermath of its frustration.

After a shower, I decided that the Master excelled at producing air and spaciousness around large and usually solid instrumental images (save with orchestral music, which is notoriously difficult if not impossible to reproduce), superbly delineating different timbres and defining aural images, and reproducing rich textures, all on deep, broad soundstages, with great punch and timing. It was just a pleasure to listen to, making music that was immersive and sensuous that could reach out from the soundstage and just grab you. Though it was easy to pick out all the items on the usual audiophile checklist, mostly I just leaned back and reveled in the gorgeous worlds of its precisely animated soundfield.


VAC’s Kevin Hayes based the Master on the two-box Signature Mk.IIa SE preamplifier ($19,990, line stage only; $26,490 with phono stage), which sits below the Master and Statement models and above the Renaissance V ($9900 line stage, $12,900 with phono), which has a smaller, loaf-of-bread power supply. The Signature Mk.IIa SE has been one of my reference preamps for two years now. With and without their phono stages, the respective differences in price between the Master and the Signature Mk.IIa SE are $8010 and $13,510. But their output impedances and recommended output loads are exactly the same, as are the tube types used and the gains produced by their line and phono stages. And because the two preamps look identical and have the same physical dimensions for both control unit and power supply, all I had to do was swap out the Master for the Signature Mk.IIa SE to make this comparison.

To compare the sounds of the Signature Mk.IIa SE and Master, I listened to the Roy Hargrove Quintet’s Earfood again and with particular care to “I’m Not So Sure,” the track that had been so gorgeous through the Master. Overall, it sounded similar in terms of tones, soundstage depth and breadth, and air around instruments. The timbres of the trumpet and alto sax were also similar in character and sensuousness. But I could tell that the impacts of drumstrokes and bass plucks were softer, not as crisp or explosive. Hargrove’s trumpet was certainly as clear as through the Master, but not as dimensional in terms of its metallic sheen or blattiness. Finally, although Justin Robinson’s alto sax still sounded fluid and expressive, it wasn’t as piercing in the highs or dynamic peaks. There was a marked difference in extension, resolution, snap, and punch.

Listening again to Florilegium’s recording of Bach’s Brandenburg Concerto No.3 confirmed all of this. Though string tone was fine and the separation of sections impressive, microdetails were not quite as refined. I couldn’t pick out single instruments as easily -- something I’d very much enjoyed doing with the Master. Pace, rhythm, and timing were good with the Signature Mk.IIa SE -- the attacks of instruments were precisely together in this performance’s myriad tight entrances -- but I couldn’t “see” as deeply into and among the aural images of the violins and viola da gamba. Yet with the Signature Mk.IIa SE, the strings were expressive and open, tutti energetic and thrilling, and harmonies bountiful.

From her opening roulades, Renée Fleming’s voice in Handel’s “Endless pleasure, endless love” was pure and airy with vocal and orchestral images that were stable but more diffuse, not as solid as with the Master. Tonal textures were superb -- the viola da gamba was very dark and mordant -- but I missed the fine, inner details of performance afforded by the Master. The definitions of instruments were less clear, the soundstage was shallower, and dynamic midrange peaks didn’t reach as far into the room. Fleming’s plush voice sounded just as sprightly, but her trills weren’t as thrilling and produced no shivers.

The Band’s recording of Richard Manuel and Bob Dylan’s “Tears of Rage” sounded much the same with the Signature, Danko’s bass big and fat and rumbling down low. Manuel’s plaintive singing struck me emotionally the same way, filling me with grief and sorrow, but may have been a touch more muted than through the Master. Soundstaging was equally good: the tapestry of voices was intricate and clear, the breadth ample. Robertson’s Telecaster squawked and squealed just as affectingly, and Helm’s drums punched and thunked thickly. Only Hudson’s organ seemed far less clear and prominent. I’d venture to say that, with a lot of rock music, you wouldn’t be losing much between VAC’s Signature Mk.IIa SE and Master.

Differences were more pronounced with vinyl. “Save Me,” from k.d. lang’s Ingénue, sounded as big and bold as a California Cabernet but not as plush as through the Master, a little hazier, and not quite as saturated sonically. Though the image of lang’s voice was solid, with beautiful tone, the midrange textures seemed more occluded and without the fine inner details presented by the Master. The soundstage shimmered, pulsing with bass, chiming guitar, quavering pedal steel. That stage extended 3’ beyond the outside edges of my speakers -- as good as I’d gotten with the Master -- but didn’t reach as far out into the room.

Likewise, Evans’s piano in “Waltz for Debby” had less presence and more muted inner details. The interplay between him and bassist LaFaro was beautifully reproduced but with a touch less impact from slapped strings, and the low-bass extension seemed truncated. This track still sounded beautiful, if not as startlingly so as with the Master -- good but not stellar.

Hands down, the Master’s sound with the same recordings was better: more emotionally affecting, blessed with finer inner details, more layered depth, and stronger visceral presence.


In 2012, when I reviewed the VAC Signature Mk.IIa for The Abso!ute Sound, I wrote that “It plays music with extraordinary finesse and drive, accurate timbres, spaciousness in the soundstage, swift attacks and aching decays, and an even spectral balance. . . . Of all the preamps that have been in my system, it is the one that most wisely balances the ofttimes contradictory qualities of superior drive and great finesse.”

Now I’ve heard the VAC Master preamp in my system, and it easily trumps the newer Signature Mk.IIa SE in every way. The Master is capable of more finesse and sonic nuance and far more convincingly reproduces tonal textures, the layering of the soundstage, and dynamic scale.


All Kevin Hayes has ever wanted his designs to do is to bring recorded music back to life. “Since 1987,” he told me, “I’ve had it in my heart that this would be my vocation. It’s been my driving urge for decades: That real voice in a real room coming alive.”

I think he’s succeeded at this as much as any other designer I know of. The Master preamp is one of the finest audio-electronics components I’ve ever had in my system. I found in it virtually no faults to speak of -- its prowess was evident with all genres of music, and its built-in phono stage was of reference level and the equal of almost any other standalone phono stage other than the most extreme luxury models I’ve heard. Though it occupies two cases, it doesn’t take up that much space for a component that performs so well, and its elegantly streamlined looks are sleek and attractive and in keeping with its fabulous quality of sound. If you’re looking for a tubed preamplifier that performs at the highest level, seriously consider auditioning the Valve Amplification Company’s Master. As the Beach Boys sang, “Don’t worry, baby” -- the VAC Master will make you come alive . . .

. . . Garrett Hongo

Associated Equipment

  • Analog sources -- TW-Acustic Raven Two turntable and Raven 10.5 tonearm,
  • Zyx 4D MC cartridge (0.24mV); Ortofon RS-309D tonearm, Miyajima Laboratory Zero MC cartridge (0.4mV)
  • Digital source -- Esoteric K-05X SACD/CD player
  • Preamplifier -- VAC Signature Mk.IIa SE
  • Power amplifiers -- VAC 200iQ, Zanden 8120
  • Speakers -- Von Schweikert Audio VR-44 Aktive with RST-5 ribbon supertweeters and Masterbuilt jumpers
  • Power cords -- Audience Au24 SX powerChord and Au24 SX powerChord MP
  • Unbalanced interconnect -- Audience Au24 SX
  • Balanced interconnects -- Audience Au24 SX, Zanden
  • Speaker cables -- Zanden
  • Power conditioner -- Audience aR6-TSSOX with Au24 SX powerChord
  • Accessories -- Oyaide R1 duplex wall outlets, edenSound FatBoy dampers, HRS damping plates, fo.Q Modrate HEM-25B and HEM-25S Pure Note Insulators, Acoustic Science Corporation SoundPanels, Zanden Audio Systems AT-1 Acoustic Tubes and AP-1 Acoustic Panels, Loricraft PRC4 record cleaner, Box Furniture S5S five-shelf rack and amp stand, Pottery Barn four-shelf hardwood console

Valve Amplification Company Master Preamplifier
Price: $28,000 USD; built-in MM/MC phono stage, add $12,000.
Warranty: Two years parts and labor (except tubes).

Valve Amplification Company
1911 N. East Avenue
Sarasota, FL 34234
Phone: (941) 952-9695

E-mail: info@vac-amps.com
Website: www.vac-amps.com