The SPL Iron v2 Mastering Compressor is a high-quality Vari-Mu compressor designed for mastering application.

The SPL Iron uses features no less than 6 valves for the rectifier stage which can be selected for different tonality, as well as another two on the input and output stages. Custom Lundahl transformers are also included in the input and output stages. The Iron uses SPL's superb 120V technology, which has been employed on the Neos, ensuring extremely high headroom and low distortion for superb sonic performance.

A selection of four Sidechain EQ filters is included to modify the compressor's behaviour, which is also augmented by AirBass and TapeRollOff switches. Being a Vari-Mu design, the ratio depends on the gain reduction; therefore, there are no ratio controls. Simply control the attack, and release of threshold to control the level of compression while the rectifier and Side Chain EQ will change the colouration and behaviour of the compressor. 

The Iron v2 now uses balanced side-chain inserts with send and return connections, replacing tho old jack connector, as well as new side-chain filter presets.