Formantus — shape your sound

Modern, cross-platform FIR and room-correction tools for loudspeakers and rooms. Design a correction by hand and from measurements, see exactly what it does, then export a filter for your convolution engine.

One-time purchase, no subscription. Works fully offline. No account.

FIRDesign showing a measured loudspeaker response with magnitude and phase charts, target and Auto-EQ correction, and the band console
FIRDesign — a measurement, target, Auto-EQ correction, and the band console, with magnitude & phase.

One family, three tools

A shared design language and stack across the whole signal chain — measure your system, design the correction, and (soon) simulate the room.

FIRDesign icon

FIRDesign Available

A linear- and minimum-phase FIR filter designer for loudspeakers and rooms. Design by hand and from measurements, then export for your convolver.

Measurement app icon

Measurement Free Coming soon

Capture your system with a sound card and microphone — sweep to impulse response with reflection gating — and hand the result straight to FIRDesign.

In development
RoomSim icon

RoomSim Coming soon

A room-acoustics app on the same stack — explore placement, modes and reflections before you reach for a filter.

In development

Why Formantus

Built in the spirit of the classic tools, brought up to date — modern, automated, and genuinely cross-platform.

Truly cross-platform

Native macOS on Apple Silicon and Intel, plus Windows and Linux on both ARM and x86. The same app, everywhere you work.

Self-contained

Every installer bundles a trimmed runtime — there is nothing else to install and no dependencies to chase.

Automated, not opaque

Auto-EQ, fidelity-aware auto-centering, an Auto window and excess-phase correction do the heavy lifting — on top of full manual control.

Works fully offline

No account, no telemetry, no phone-home. License activation is offline too. Your work stays on your machine.

Actively developed

A current product, not a frozen one. All 1.x updates are free for license holders.

See exactly what you did

High-resolution charts for magnitude, phase, group delay, impulse and error, with an audibility-graded design check.

Ready to shape your sound?

Try every feature free, then unlock with a one-time $39 license. No subscription, no account.