Signature Mk IIa / Signature SE
Preamplifier

Not long ago, the Signature Mk IIa was the finest preamplifier you could buy. In production since 2000, this enduring classic marked the introduction of the basic, fully balanced, zero-feedback, transformer-coupled Class A1 triode topology found in all contemporary VAC preamplifiers. Even from this early form, it preserves and reproduces the emotion and vitality of music and maximizes the performances of the associated source components and power amplifiers.

Product Brochure
Signature Mk IIa
  • The Signature’s line stage has no coupling capacitors to detract from the purity and detail of the hand-wired circuit. With no loop feedback, the output is stable and free from dynamic interactions with the load. Six standard line inputs (five when phono is fitted) are present, as well as a fully balanced Cinema Bypass input.

    The optional six-tube phono stage is sensitive and quiet, compatible with low-output, moving coil cartridges. Gain is adjustable, as is resistive loading. Electrostatic decoupling prevents the heater circuits from “talking” to each other, a common cause of lost detail. A separate power transformer is used, eliminating any disturbance of the delicate phono signal by the powerful line stage.

    The VAC logos are backlit in an elegant blue in normal operation, and display red when the mute is activated. These are set in the heirloom-quality sculpted 3/8” faceplate.

    The Signature SE (Special Edition) upgrades the input transformers to the premium designs used in the Statement and Master ranges.

     
  • SIGNATURE MK IIA Optional MM/MC phono stage with user adjustable loading

    Gain

    12 dB

    Inputs

    • 3 sets RCA line input
    • 2 sets balanced/RCA selectable inputs
    • set RCA cinema bypass input
    • Optional 1 MM and 1 MC (or additional line input if phono is not fitted)

    Outputs

    • 2 sets RCA
    • 2 sets balanced XLR (EIA “pin 2 hot” studio standard)

    Tubes

    2x 12AU7
    2x 8416, 7308, 6922, E88CC, ECC88, 6DJ8, (or 12DJ8 twin triodes)

    Absolute Phase

    correct from all inputs to all outputs

    Frequency Response

    Flat over audio band
    –3 dB bandwidth 5 Hz – 210 kHz

    THD

    <0.009% @ 1 kHz, 1 V RMS

    Maximum Output

    > 8 V RMS

    Output Impedance

    < 150 ohms, 20 Hz - 20 kHz, static (i.e., not dependent upon feedback)

    Maximum Input

    Infinite signal (attenuation precedes the gain circuitry)

    Recommended Output Load

    > 300 ohms

    Power

    External power supply, detachable umbilical cable, detachable IEC power cord

    Cinema Bypass

    Yes

    Voltage

    May be ordered for 100v, 120v, 220v, or 230/240v operation

    Remote Control

    included

    Illumination

    Illuminated logo may be switched off

    Finish

    Hand-rubbed gold-flake gloss black lacquer with chrome knobs standard.

    Hand-rubbed metallic gloss silver lacquer with chrome knobs special order with additional cost.

    Warranty

    Two years parts and labor, excluding tubes (USA, see manual for full details)

    Dimensions (H x W x D)

    Audio chassis (not including knobs and connectors): 5.5" x 18" x 14.5" (14 cm x 45.7 cm x 36.8 cm)

    Power supply (not including connectors): 4.3" x 18" x 14.5" (10.9 cm x 45.7 cm x 36.8 cm)

    Shipping Weight

    With phono: 61 lbs. (27.7 kg.)

     

    Phono Stage (optional)

    Tubes

    6x 12AX7

    Gain

    44 dB MM
    64 dB MC

    Frequency Response

    RIAA standard +/- 0.2 dB (20 Hz - 20 kHz)
    -3 dB bandwidth 10 Hz - • 80 kHz

    Channel Seperation

    > 80 dB @ 1 kHz

    Maximum Input

    > 130 mv @ 1 kHz, MM
    > 13 mv, MC

    MC Load Impedance

    selectable, 470, 300, 250, 200, 150, and 100 ohms

    MM Load Impedance

    selectable, 47k, 30k, 25k, 15k, and 10k ohms

    Overload

    117MV @ 1kHz = 8 volts RMS output; 460MV @ 10kHz

    Residual Noise

    Less than 3MV at output (s/n ratio greater than approx. 69db

    *Specifications subject to change without notice.

     
  • “Kevin Hayes has really outdone himself with the VAC Signature IIa preamp. A statement piece at a luxury price, it plays music with extraordinary finesse and drive, accurate timbres, spaciousness in the soundstage, swift attacks and aching decays, and an even spectral balance.”
    - The Absolute Sound, September 2012


    “"The sound is gorgeous - capable of handling rock, jazz, or classical music equally well."”
    - 2012 Editors Choice Award, March 2012 - The Absolute Sound


    “That’s pretty much how it goes with VAC gear – whatever it is connected to sounds about as good as it’s going to get! ... The Signature Preamplifier Mk 2 is suitable for the most exquisite of audio systems, and thus is recommended without reservation!”
    - Doug Schroeder, DaGoGo, March 2010


    “A Music-Lover’s Delight ... imaging isn’t good or even very good, it is out of this world; and it’s out of the speakers. I wouldn’t call it three-dimensional, I’d call multi-dimensional with instruments on the (invisible) soundstage in revealing focus ... its dynamic range — was beyond compare and it was quite evident that the VAC’s presence heightened the system’s musical caliber.”
    - The Inner Ear Magazine, February 2010


    Signature Preamplifier Mk II, full review - Stereophile, October 2002