IGS Audio One Leveling Amplifier

Optical Compressor

Our price:$2,750.00 GST
Order Code: ONE-LA

IN STOCK 1 (more can be backordered)

IGS Audio ONE LA is an optical compressor, inspired by the legendary solution well known from the ’60s. This is a very easy to use and great sounding tool.

ONE LA is an input and output transformer balanced, full tube device. The input of the system includes an IGS Audio 2510 transformer, the output an IGS 15k/600. Two 6N1P-EW dual-triodes are installed on the audio circuit, while the compression circuit is equipped with the 6N2P-EW triode and the 6AQ5 pentode, which control the work of the T4Bx photocell.

The One LA 19″ has simple controls: a Peak-Reduction knob controls the gain of the side-chain circuit, and therefore, the gain reduction threshold; Gain Control for the make-up gain; and a Limit/Compress switch to alter the compression ratio. The VU meter may also be switched to show gain reduction or output level.

T4Bx optocell

The original solution used the TELETRONIX electroluminescent panel, that was illuminating the photo resistor. The idea of opto-compression originated in the past is still being cultivated today. IGS Audio has developed its own photocell equivalent to T4B called T4BX. The use of carefully selected components in the production of the T4BX photocell, and their individual measurement and matching, result in completely repetitive sound qualities of each device.

Not the piece of gear you’re looking for?

For more hand-made IGS Audio recording channels and signal processing, check our IGS Audio brand page here

Device type
Optical Compressor Yes, T4Bx or T4B photocell
Basic features
Stereo Link Yes, RCA-RCA cable
All stepped manipulators 24 step Elma switches
Input & Output
Input Impedance (balanced) 600 Ohm, IGS Audio custom transformer
Output Impedance (balanced) 600 Ohm, IGS Audio custom transformer
Audio transformers IGS Audio custom transformer
Operating Level +4dBu
Max input level +16dBu
Max output level +18dBu
Dynamic Range >110 dBA (@ 1kHz, +24 dBu)
Max. gain 30dB
Max Gain Reduction 36 dB
Time constants
Attack: 1ms
Release: 0.5 – 5s (50% @ 60ms)
Distortion (@ 20 Hz – 20 kHz)
THD+N 85 dB (A)
Voltage 115/230V AC, 50 – 60Hz
Power consumption 40W
Power supply Internal
Tube set 2x6N1P-EW, 6N2P-EW, 6AQ5

You may also like…