VNE Vacuum Tube Compression Amplifier
HAZELRIGG INDUSTRIES
14
The LED is calibrated to turn red when nearing the upper input level of most digital audio
convertors.
Gain Reduction indicator (4)
The Gain Reduction meter consists of 10 LEDs calibrated to give an intuitive sense of the amount
of compression. The LEDs are scaled so that the first 7 LEDs represent approximately 1dB of
compression each, while final 3 LEDs cover the range to about 15dB of compression.
Attack (5)
This control adjusts the time it takes the VNE gain reduction circuitry to react to a signal. It might seem
that the faster the attack time, the better, but very fast attack times will result in significant distortion on
material with a lot of low frequency content (this is true of all compressors). As the control is turned
clockwise, the attack time becomes longer. Often with percussive sounds it is advantageous to have fairly
long attack times to allow the initial transient of the sound to pass through the VNE without gain reduction.
Experiment with the Attack control on percussive material to see how it changes the sound. Generally
speaking, a fast attack time is best when complete control of the maximum instantaneous level is required.
This might be desirable to protect a digital input from overload. However, a more natural sound is usually
obtained with a slightly slower attack time. Long attack times can be useful as an effect, adding power to
percussive instruments.
Release (6)
The Release control adjusts how long it takes for the gain to return to normal after a sound ceases (or drops
in level). Fast release times add more energy to the sound, but can add distortion to low frequency sounds.
(This is true of all compressors.) A fast release time adds density to the sound, often with the compression
becoming more obvious. Long release times make the compression less obvious and more natural, but can
“punch holes” in the lower level audio under certain conditions of high percussive levels.
Gain (7)
Whenever compression is applied, the signal is reduced in level by the amount of gain reduction. The Gain
control allows you to make up the lost gain as necessary. The maximum gain available is about 15dB.