The Alice 538 Lunchbox OPTO Stereo Compressor has
 
Ted Fletcher’s historic opto compression design
Perfect ‘Hard-Wired’ by-pass for instant comparisons
Wide range ratios from gentle to brutal
Accurate UV compression metering on a real meter
Extreme stereo width control
 
The 538T is designed for creative compression effects that are difficult to achieve with plug-ins. It’s capable of extreme compression just as Ted’s original Joe Meek SC2 V5; amazing drum sounds! It’s also super-quality ‘Levelling Amplifier’ with the sparkle of a well-designed opto compressor
 
Mechanical
The 538T occupies two spaces in a standard API 500 series rack using normal ins and outs for left and right
 
Inputs & Outputs
Left and Right balanced or unbalanced inputs
Left and Right balanced outputs via hand matched OEP Z3001C canned transformers
 
Imaging
Variable width control from full ‘mono’ via true L/R stereo up to 150% stereo width
 
Metering
Easy-to-read analogue meter reading audio (UV) or compression depth (comp)
 
Specification
INPUTS · 10K impedance differential balanced.
OUTPUTS · Floating balanced 50 ohm.  Max balanced output approx. +26dBu
GAIN · Maximum 24dB
NOISE · At least 80dB below operating level Dynamic range exceeds 100dB.
HARMONIC DISTORTION · Generally within 0.005%. 2nd order harmonic distortion rises at lower frequencies under compression.
AMPLITUDE FREQUENCY RESPONSE · Line in 20Hz to 20KHz within 1dB.
AUDIO CROSSTALK · the 538 uses M/S processing (sum and difference) with ‘side’ content variable via the width control. With width set at 100% L/R crosstalk can be better than -50dB.
COMPRESSOR · Photoresistive servo operated feedback type· Ratio non-linear;  minimum approx. 1.2 to 1 maximum approx. 8 to 1. Sidechain filtered for correct bass compression.Attack time 1mS min. 10mS max. (variable) Release time 200mS min 1.5S max. (variable)
CONNECTIONS · via 2 X 500 series sockets.
POWER · 3  Watts. Powered from 500 series rack. +ve rail 68mA, -ve rail 106mA.
HOUSING · 2 spaces of 500 series rack.