IGS / Products / Compressors / One Leveling Amplifier

One Leveling Amplifier

The IGS 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

Design

The IGS 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.

Simply adjust the input Gain and Peak Reduction

Controls

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.

It is known that in the case of ONE LA the nature of the device depends on the T4B photo-cell

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.

Stereo pair

Matched pairs are also available. The link socket is located on the rear panel. The RCA-RCA cable is all you need to link two units. Perfect stereo matching is achieved by hand selected tubes and Elma switches.

The One La 19" has a sonic character that makes it sought after by many recording engineers

  • Device type
    • Fet CompressorYes, T4Bx or T4B photocell
  • Basic features
    • All stepped manipulators24 step Elma switches
    • Stereo LinkYes, RCA-RCA cable
  • Input & Output
    • Audio transformersIGS Audio custom transformer
    • Input Impedance (balanced)600 Ohm, IGS Audio custom transformer
    • Output Impedance (balanced)600 Ohm, IGS Audio custom transformer
  • Levels
    • Operating Level+4dBu
    • Max input level+16dBu
    • Max output level+18dBu
    • Dynamic Range>110 dBA (@ 1kHz, +24 dBu)
    • Max Gain Reduction36 dB
    • Max. gain30dB
  • Time constants
    • Attack10ms
    • Release0.5 – 5s (50% @ 60ms)
  • Distortion (@ 20 Hz - 20 kHz)
    • THD+N85 dB (A)
  • Power
    • Voltage115/230V AC, 50 - 60Hz
    • Power consumption40W
    • Power supplyInternal
  • Packing box
    • Dimensions70 x 50 x 30cm
    • Shipping weight7kg
  • Others
    • Tube set2x6N1P-EW, 6N2P-EW, 6AQ5