IGS Audio / Alter 500

The IGS Audio/Alter 500 is a mono FET compressor compatible with the 500 series. Its stepped input/output adjustment and three-stage attack/release settings make it easy to recreate your desired sound. It also features an independent slam mode, making it ideal for those who want to enjoy aggressive compression.

The ALTER 500 is a FET compressor conforming to the 500 standard. The FET type solution was first used in the legendary 1970s UREI 1176 compressor. The ALTER is a single-channel unit with stepped input/output controls. The ratio switch has six positions, including the original 1:1 and 2:1 of the 1176, plus two additional positions. Slam mode can be activated with a separate switch and operates regardless of the ratio setting. Attack and release times can be set to Fast/Mid/Slow using a 3-pole switch.