Balanced Audio Technology VK-90 Tube Preamplifier

Second-generation transformer-coupled outputs provide exceptional purity

Featuring transformer-coupled, high-current, single-gain stage topology, VK-90 is the finest single-chassis preamplifier ever created by Balanced Audio Technology. Wound with Cardas’ finest copper wire, the second-generation transformer-coupled outputs catapult the performance of this fully balanced, zero-feedback design to a reference level.

Each transformer comes encapsulated within a mu-metal shield for the ultimate in signal purity and noise isolation. Electrically, these second-generation transformers improve VK-90’s ability to drive low-impedance loads. Sonically, they offer greater transparency than the already revered performance established by BAT’s first-generation transformer design.  

Flexible User Interface

Boasting one of the most flexible user interfaces in the industry, VK-90 offers customizable options that range from dimming to fading and source-naming. It can also be fully upgraded to a REX 3 preamplifier. And you can always get the volume just right courtesy of a proprietary electronic shunt volume attenuator that offers 140 steps of 0.5 dB resolution. In the design, discrete metal film resistors bleed the unused signal to ground. From deep bass to extraordinary dynamics and layered transparency, VK-90 is your new reference. 

Eight 6H30 SuperTubes

More than a decade ago, BAT introduced the world to the 6H30 SuperTube. VK-90 continues the tradition by using eight 6H30 SuperTubes to form an extraordinarily high-current, low-impedance drive engine. The signal is effectively transmitted through only one gain stage. The Unistage™ circuit provides the ultimate simplicity of amplifying the incoming signal only once, while using no global feedback to double back on the straight-through signal integrity.

SuperPak Power

The VK-90 preamplifier features Balanced Audio Technology’s all-new, third-generation SuperPak in its power supply. The design represents a significant rethinking of what is possible from an energy storage device. The SuperPak features hybrid construction with two capacitors built and potted into each individual low-resonance shell. An additional silver-in-oil capacitor—arguably the finest-quality capacitor offered at any price in the industry—is used as part of the Gen 3’s construction. The result: Low-level detail is revealed in a clear and unforced manner, while the overall sound takes on a beguiling sweetness and naturalness from top to bottom.

Features

• Third generation SuperPak with 4×50 uF with internal silver/oil hybrid construction
• Silver gold oil bypass caps
• Unistage design with only one gain block and no capacitors in signal path
• Output second generation output transformers with Cardas OFC wiring
• Zero global feedback

• Absolute polarity switchable

Specifications

Inputs: 5 x XLR

Outputs: 2 x XLR, 1 x XLR (Tape)

Gain: 18 dB

Vol Control Resolution: 140 x 0.5 dB steps

Tube Complement: 4 x 6H30, 2 x 6C19

Input Impedance (min): 100 kΩ

Output Impedance: 200 Ω

Power Consumption: 250 VA

Dimensions: 19″ x 5.75″ x 15.5″

Weight: 40 lb