SSL E-Series Dynamics - 500 Series

A true RMS converter is used in the side chain while the gain element is an all discrete design identical to the Class A VCA chip used in the original unit. The compressor contains additional switching options to defeat the over-easy curve and to use a linear release instead of the more usual logarithmic curve. The result is a compressor with three distinct voices, each with its own musical character.

Compressor/Limiter

• Ratio
• When turned to 1:1, the compressor/limiter section is inactive. Turning the control clockwise increases the compression ratio, giving a true limiter at the fully clockwise position. The compressor normally has an ‘over-easy’ characteristic – pressing the button replaces this with a ‘hard knee’ characteristic, providing an alternative for some instruments.
• Thresh
• Whenever a signal exceeds the level set by this control, the compressor will start to act at the ratio set by the RATIO control. The THRESHOLD and RATIO controls also provide automatic make-up gain, so as you lower the threshold and introduce more compression, the output level is increased, maintaining a steady output level regardless of the amount of compression.
• Lin Rel
• Changes the release curve from logarithmic to linear. This also raises the threshold by 6dB.
• Fast Att
• Provides a faster attack time (3mS for 20dB gain reduction). When off the attack time is slower and less aggressive (30mS for 20dB gain reduction).
• Release
• Sets the time constant (speed) with which the compressor returns to normal gain settings once the signal has passed its maximum.

Gate/Expander

• Range
• Determines the depth of gating or expansion. When turned fully anti-clockwise, this section is inactive. When turned fully clockwise, a gate depth or range of 40dB can be obtained.
• Thresh
• Determines the level at which the gate opens or the level below which gain reduction begins (EXP selected), adjustable from approximately -30dBu to +10dBu. Variable hysteresis is incorporated in the threshold circuitry which increases as the threshold is lowered. This is very useful in music recording as it allows instruments to decay below the ‘open’ threshold before gating or expansion takes place.
• Fast Att
• Normally, a controlled linear attack time of 1.5ms per 40dB is provided. Press this button to select a fast attack time (100µs per 40dB). The attack time is the time taken for the Gate/Expander to ‘open’ once the signal level is above the threshold. When gating signals with a steep rising edge, such as drums, a slow attack may effectively mask the initial ‘THWACK’, so you should be aware of this when selecting the appropriate attack time.
• Release
• This determines the time constant (speed), variable from 0.1 to 4 seconds, at which the Gate/Expander reduces the signal level once it has passed below the threshold. Note that this control interacts with the RANGE control.