IGS Audio A-Type 525

The IGS A-Type 500 compressor/limiter is inspired by a legendary American design from the 1970s. The circuit is built entirely with discrete components in a through-hole assembly. The compressor input is balanced by the SSM2141 op-amp, while the output is transformer-balanced. An additional, second audio transformer is responsible for the feedback signal, which, after adjusting the time constants, returns to the compression control element, the VCR (Voltage Controlled Resistor). The control signal has a negative value relative to the circuit ground, and its value directly affects the VCR resistance, which in turn adjusts the gain of the first amplification stage.

INPUT & OUTPUT:

Audio transformers: Yes, IGS custom transformers

Input Impedance (balanced): 10k, SSM2141

Output Impedance (balanced): 75 Ohm, IGS custom transformer

LEVELS:

Operating Level: +4 dBu

Max input level: +27 dBu

Max output level: +28 dBu

Max Gain Reduction: -25 dB

Max. gain: 25 dB

Noise Level: -99 dBA

TIME CONSTANTS:

Attack: 15us

Release: 100ms - 2s

Ratio: 2:1, 20:1

BANDWIDTH:

Frequency response: 8 Hz to 20 kHz, +/- 0.1dB

DISTORTION (@ 20 HZ - 20 KHZ)

THD+N: 0.014%

POWER:

Power consumption: Power consumption: 2.5W

PACKING BOX:

Shipping weight: 1kg