Overview

Knif Solmu is a versatile audio compressor intended for audio mastering and mixing applications. It is equipped with MS encoding and decoding, parallel compression capability, diverse filtering options, and a wide variety of precision adjustments for ultimate versatility.

Gain reduction is executed by a transformer coupled MOSFET push-pull gain topology that is loosely following the footsteps of classic vacuum tube variable mu compressors. The set of twelve discrete MOSFET transistors is tightly matched based on several parameters, and the temperature of the circuit is elevated to about 70 °C for increased thermal stability regardless of ambient conditions.

The character of the unit is dominated by the gain reduction circuit and the interstage transformers; while the rest of the circuit utilizes a mixture of Knif discrete class-A amplifiers and the best available JFET input IC operational amplifiers for absolute transparency. The permalloy core interstage transformers are bifilar wound and housed in mu-metal shields which contributes to wide bandwidth, high headroom, and low noise.

Solmu also features a GR offset – a novel control for increasing the third harmonic distortion by moving the normal, no compression state along the gain reduction curve.