The Knif Audio Soma sits in the rare upper echelon of mastering gear where meticulous engineering meets musical transparency. Rather than relying on simple, off-the-shelf circuit topologies, Jonte Knif addressed one of the biggest drawbacks of traditional passive designs—the unwanted interaction between bandwidth and gain—by introducing true variable Q adjustments.

The Knif Soma is an exceptional tool for mastering engineers who need precise, recallable equalization without sacrificing the natural weight and air of analog gear. It offers the surgical accuracy expected from modern digital processors alongside the effortless musicality of a high-end passive tube network.

Includes spare tube

The Knif Audio Soma is a dual-channel passive tube equalizer designed by boutique analog designer Jonte Knif, specifically built for high-end audio mastering and mixing applications.

Overview & Design Concept

The Soma represents a clear departure from the traditional paradigm that passive EQs are only suitable for broad, general tonal shaping.Unlike classic passive EQs that use simple resistor-based Q adjustments (which inherently alter the boost/cut amount alongside bandwidth), the Soma features "Real Q Adjustment."This innovation gives mastering engineers true precision and predictability across variable bandwidths without sacrificing the smooth, transparent qualities typical of passive LC filter circuits.

Key Hardware Features & Build Quality

• Ultra-Short Signal Path:To preserve signal purity and dynamic response, frequency and Q adjustments (utilizing switched capacitors and inductors) are performed locally right at the circuit board. Signal travels to the front panel for gain control only.

• True Passive M/S Matrix:Includes a fully passive, transformer-based Mid/Side matrix. It utilizes local relay switching on transformer windings to perform sum and difference processing without adding extra active components into the signal chain.

• Tube Makeup Gain Stage:Uses a two-stage tube makeup amplifier with moderate feedback paired with custom mu-shielded Lundahl transformers, producing a smooth, transparent tone with high headroom and subtle analog warmth when driven.

• Stepped Controls for Precision:Fitted with Swiss-made Elma stepped rotary switches with soft-touch collet knobs, allowing for total recall during mastering sessions.

• No-Compromise Build:Constructed with Teflon/copper/silver wiring, discrete regulated anode power supplies, and zero connectors in the direct audio path for long-term reliability.