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VAC Signature Preamplifier Mk 2 Review

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300 Ohm Output Load

Regarding the Signature 2 having a 300 Ohm output load Kevin notes, “…This is done to provide the circuit with a predictable operating environment… the load presented by any power amplifier is insignificant in comparison… like a single drop of rain in the ocean.” While the description is hyperbolic, I found in practice that it literally could handle with ease any amp I threw at it. As Kevin asserted, it can be partnered with amps having nearly any input impedance. As Kevin relates, “…the performance is the same whether you have a VAC amp with 100,000 Ohm input or a Pass Labs with 5,000 Ohm input impedance.” I used the Signature II with three very different amps, the Azur 840W (input impedance XLR 38 kΩ; RCA 68 kΩ), the Moscode 402Au (100 kΩ), and the Class D Jeff Rowland 501 Mono Blocks (40 kΩ). Every one excelled in advance of any other configuration in which it was placed (I typically develop no less than three or four systems with each component I review). The VAC lifted each one on its back and carried them all over perceived performance barriers – easily.

Voicing with Radically Different Speakers

A fundamental practice at VAC is to minimize the influence of possible shading of the component’s sound due to use of a favored speaker in voicing process. Kevin shares, “…the amplifier designer is in danger of shading his work in a way that complements the speaker’s shortcomings. I term this a ‘complementary error’.” He continues, “Back in the mid-1980’s I remember hearing a mainline tube amplifier sing beautifully on a pair of Martin Logan CLS’s, and fall flat on its face with a pair of Snell A-III’s. Interestingly, I later heard that this company used Quads as their exclusive reference. This experience taught me a lesson.”

Consequently, Kevin uses several speakers of distinctly different design in a process he calls “Triangulation”. In order for an improvement to truly be an improvement, it must result in better sound on some or all the speakers and sound worse on none of them. The method obviously works, as not only amps benefit from the Signature 2, but also the variety of speakers I paired with it sounded improved. My experience, without fail, was that just as amps were benefited by the Signature 2, so also speakers benefited. Both the Legacy Audio Focus SE full range floor stander and the Kingsound King full-range ESL sang beautifully with this preamp. These are radically different speakers, and one might think that the VAC might favor one or the other, but indeed, the preamplifier sounded remarkable through both speakers.

Putting these and other design parameters together it becomes easier to see that the Signature 2 is far more gracious toward amps and speakers lying outside a narrowly defined range of performance. While other preamps might operate optimally only with compatible devices, the VAC is an instrument made to attain to the pinnacle of performance with nearly any better than average amp or speakers. It accommodates them exceptionally well, and thus makes them perform their best. Like the point guard on the championship team who feeds the crowd favorite power forward, every little maneuver and assist has been worked to make the system’s “power player” stand out and be its best.

Some basketball fans obsess about the role of the power forward or center (With an assist from media like the sacrilegious Lebron James Nike commercials portraying him as a basketball messiah), neglecting to tally the innumerable benefits of the point guard. Similarly, audiophiles are tempted to glance past the critical importance of the preamp which sets the stage for the amp to sound impressive. Quite literally, when the Signature 2 was removed from the system with any of these amps the soundstage collapsed, the imaging splayed, the sense of élan vital faded. The music became a lifeless thing instead of an entity with the breath of life in it.

Of course, in pursuit of an ultimate rig it would not be recommended to pair such an instrument as the Signature 2 with any old components and speakers; obviously the effort would be made to find commensurate gear. When one takes the time to carefully match the system to the grandeur of the Signature 2, one experiences High Fidelity at its best. However, if you were upgrading to Ultimate Audio status one piece at a time, you would have difficulty doing better than starting with the Signature 2.

Rear panel of the VAC Signature Preamplifier Mk 2

Priming The Super-Review System

As mentioned previously, I obtained the Signature Preamplifier MkII specifically for use with the Super-review system. Two principle observations emerged:

The transparency of tone was stunning, as clear to the ear as crystal is to the eye. The attributes of a diamond, the four “C’s” are clarity, color, cut and carat weight. It is notoriously difficult to determine a diamond’s clarity and transparency apart from a chart, or another diamond. The two other preamps on hand, the Cambridge Audio Azur 840E and the Jeff Rowland Capri, both sounded quite clean in their own right. However, when compared directly to the reference quality Signature 2, both exuded pleasing but distinct colorations and less clarity. This should be expected as the VAC is a price-no-object component; as such it lived up to its reputation for pristine sound.
It made Class D sound worthy of higher echelon systems. I had used the Channel Islands and Wyred4Sound amps previously, but I preferred the robustness of the Jeff Rowland 501 monos. I worried over the white, or clinical, sound of Class D, however most of it had dissipated with the use of the VAC. The Legacy Helix speaker system reached its peak only with the VAC. As soon as possible, after due comparisons and observations, the VAC remained in the Super-review rig the duration of the Helix’s time with me. In a cost-no-object system in which there was use of Class D amplification I would not want to be without the capabilities of the Signature 2. In fact, as to its performance, I wouldn’t want to be without the Signature II in any cost-no-object system!

Full vs. Flat Sounding

The Helix rig was an invitation to revisit classic rock, and I did so with gusto, listening again to the Steve Miller Band, Kansas, Emerson, Lake and Palmer, and the Moody Blues, among others. Hearing ELP leads me to use the term “atmospheric” to describe the impact of the Signature Mk 2 in the rig. On good audio systems the clues as to the size of the space become much more discernible. The preamp plays a critical role in the creation of the sense of fullness to instruments and expansiveness to the venue.

One might loosely categorize preamps into two genres, as “Flat” or “Full” sounding. Flat sounding preamps hit all the right notes technically, but struggle to extend the musical notes to the outer perimeter of the recording venue. The notes don’t seem energized and extended to their fullest, like projectiles fired at the walls from a rubber band gun rather than a rifle. Flat sounding preamps don’t re-create the atmosphere of the recording terribly well. The VAC, in contrast, pushes out the soundstage well beyond the vicinity of the instrument. Notes are luminescent, plump with full expression of the physical excitement of a reed or string, and dead on tonally. The very limits of the space are explored intimately. As a result the experience of listening to music with the Signature 2 is that of being immersed far deeper into the sound space than with a flat sounding preamp.

An example of this deepening of the experience was found in Spyro Gyra’s Morning Dance, which can suffer the effects of sounding flat, lacking in treble sparkle, bass string snap, and midrange immediacy. In the past I had chalked it up to the age of the recording. However, the Signature 2 surprised me by revitalizing it. I especially take note of music with xylophone, as my grandmother used to play it. When the xylophone is heard on a less than top-notch preamp, the notes of the wooden bars struck with a mallet have no reverberation; they simply “plunk” at the correct pitch and die. However, when heard on the VAC the notes contain reverberation! One can actually hear the woody decay of the note! I thrilled to hear not only gorgeous solidity but also the resonance of the wooden bars as they were hammered.

On nearly the opposite end of the spectrum, I also was bowled over by the sound of harmonica as heard through the Signature 2. One of my favorite recordings of the harmonica is Goodbye Blue Sky by Kevin Godley and Lol Creme. The instrument is used in a range extending from bass to treble, and at times with two players acting as a “harmonica section” with solos. “The Last Page of History”, has a particularly rousing rock-blues feel. The Signature 2 entwines but doesn’t lose each slippery note as the players puff into the tiny portals of the instrument while whipping it back and forth across their lips. A special treat is the interplay of each note of the solo harmonica on “Desperate Times” with its anti-note reverberating from the walls of the recording venue. One hears the pitch of the gulp of air indicating the “rest” as the harp is played so powerfully that the emptied lung reflexively fills; there is not time to pull the instrument away from the mouth while continuing the reedy fusillade. In all this, there is no harshness with the harmonica, no edge, no biting shrillness; there is an exceptional amount of glam, without a trace of glare.

3 Responses to VAC Signature Preamplifier Mk 2 Review

  1. bzr says:

    Doug Schroeder article on the VAC Signature Preamplifier Mk 2 Review. One of the better reviews that has made my mind up to buy one of these pre-amps, thanks Doug!

  2. Alonski says:

    Ditto. Doug, your review was instrumental (pun intended) in my decision to purchase this preamp to replace my beloved VAC Standard LE preamp. In terms of upgrades, this represents a significant jump from one end of the spectrum of VAC offerings to the top of the range (well, almost. The new VAC Statement Line Stage $47k and Phono Pre $50k are on another planet altogether).

    My Signature 2a just arrived with Phono option installed. I’ll be setting it up and burning it in over this weekend. If even half of what you’ve experienced with this pre comes to pass in my system, sonic euphoria will be experienced. If most or all the benefits you wrote of show themselves, especially since I’m connecting it to my VAC Phi 200 amp, there will be no leaving the house for a few weeks (and I’ll hold you accountable!).

    Thanks Doug, I’ll post my impressions on A’gon when I emerge from the Man Cave, no doubt needing a shave, a shower, and some sleep.


  3. Alex says:

    Hello! Do you think this preamp (or the Statement Line) could have a really good sinergy with Audiopax amps, especially the Maggiore M100? Thanks!

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