VT-4 Single Channel Vacuum Tube Equalizer

The VT-4 Vacuum Tube Equalizer will change the way you think of EQ. It is smooth, sweet and very subtle at mild settings, but can also be aggressive when needed. Creative use of the low boost and cut will create a powerful bass that must be heard to be believed. The high boost adds just the right brightness or sparkle to vocals, guitars, keyboards, percussion, strings… you get it. Equally suited for gentle tone contouring as well as extreme sound sculpting, the VT-4 lets your music shine through with no harsh artifacts.

The VT-4 uses passive LC circuitry with class-A triode vacuum tube stages for the input and output. The tube circuitry is largely derived from the VT-1/VT-2 mic preamp design, ensuring that the equalizer has much the same sonic character as the preamps. Based on classic designs, the LC-style passive equalization circuitry is still the best-sounding way to achieve high-quality, musical tonal control.

The input is line-level, transformer balanced-bridging and the active vacuum tube input section features adjustable gain to accommodate input signals as low as -10 dBm. The input transformer is made by Jensen and the output stage utilizes the same custom Jensen transformer used on the VT-1,VT-2 and VT-24 microphone preamplifiers.

All controls are stepped for precise repeatability and uniform matching between units. High-quality rotary switches are used with 1% metal-film resistors. All of the audio capacitors are polystyrene or polypropylene. The inductors are custom-made for us by Jensen Transformers Inc.

The equalizer is constructed of heavy-gauge aluminum, with a 3RU (5.25 inch), 1/4-inch thick front panel, finished in D.W. Fearn red. It matches the VT-1/VT-2 series of mic preamps in appearance and construction.

Like the VT-1/VT-2 preamps, the VT-4 has been designed to be an exceptional tool for audio professionals. The design frequencies and curves were determined by ear, after extensive listening to a variety of program material, both individual tracks and overall mixes. The result is a highly-musical equalizer with plenty of range for enhancing any track.

Performance (EQ out)

Frequency response: +/- 0.2 dB 20 Hz to 20 kHz
THD: less than 0.06%
Signal-to-Noise: better than 80 dB


Specifications
(All controls are independent and can be used in any combination)
Low Cut at 30, 40, 100, or 400 Hz, 0 to -18 dB shelving in 2 dB steps
Low Boost at 20, 40, 60, or 140 Hz, 0 to 16 dB shelving in 2 dB steps
Mid Cut at 200, 300, 400, 500, 600, or 700 Hz, 0 to -16 dB in 2 dB steps
High Boost at 1.5, 3, 4, 5, 8, 10, 12, or 16 kHz, 0 to 12 dB in 2 dB steps
High Bandwidth Q of 0.6, 0.8, 1.0, 1.4, or 1.7
High Frequency Cut at 1.5, 3.5, 8, or 28 kHz, 0 to -14 dB shelving in 2 dB steps
Gain adjustable from -9 to +9 dB, referenced to +4 dBm, in 3 dB steps
NOTE: Frequency is specified in cycles per second (cps) or kilocycles per second (kc). These units correspond to Hz and kHz respectively. Measurements made with -50 dBm input and 50 dB gain in a 22 cps to 22 kc bandwidth.

Specifications and price subject to change without notice.