The IGS A-Type 500 is a compact yet powerful compressor/limiter that takes inspiration from a legendary 1970s American design, featuring fully discrete components and transformer-balanced output. With a unique "Compress" switch, this unit simplifies compression by adjusting both Gain and Threshold simultaneously, while still offering precise control with dedicated Threshold and Output knobs. Known for its ultra-fast 15μs attack time, it operates in both Compressor (2:1) and Limiter (20:1) modes, with four selectable Release times, making it perfect for taming peaks. Its versatility shines on vocals, guitars, percussion, and more, offering great results whether used for tracking, mixdown, or program compression.
Product Features:
- Reissue of the original American "feedback" compressor with fully discrete design and balanced input/output
- Features variable threshold, output, and "Compress" control for dynamic adjustments without level changes
- Offers fast attack (15µs), four release modes, and a De-Ess function for reducing sibilance in vocals
Compact design while maintaining all classic compressor features
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.
Simple and fast operation thanks to the intelligent Gain control system
The compressor is equipped with a unique set of controls, including a „Compress” switch that simultaneously changes both Gain and Threshold values. This allows you to adjust compression parameters while maintaining constant peak signal levels. Additionally, separate Threshold and Output knobs allow for precise control over the compressor’s activation point and output signal.
Ultra-fast attack for perfect peak control
The device offers two modes of operation: Compressor (2:1) and Limiter (20:1). The Attack time is fixed and very fast at 15μs. The Release time can be set to one of four options: 0.1s, 0.5s, 1.5s, and 2.0s. An additional mode is the de-esser, designed to reduce sibilance in vocal recordings.
Applications
The A-Type 500 has a wide range of applications. It works exceptionally well on vocal tracks, acoustic and bass guitars, various percussion instruments, and many other sources.
Bullet: Suitable for tracking, mixdown, or program compression, with hardwire bypass and multi-unit linking capability.
For more information on this or any other IGS Audio product, visit www.igsaudio.com.