Room EQ Wizard (REW)
Free acoustic measurement software for analysing room behaviour and loudspeaker response.
What it is
About Room EQ Wizard (REW)
Room EQ Wizard (REW) is free software for measuring and analysing acoustic environments — rooms, loudspeakers, and audio interfaces. It generates test signals, measures the frequency response and impulse response of a space, calculates reverberation times (RT60), and identifies modal resonances. Used by acoustic consultants, studio designers, home studio builders, and live sound engineers to understand how a space behaves before treating or equalising it.
What you can do with it
Capabilities
Measure the frequency response of a room or speaker by playing a swept sine signal and recording the result
Calculate room reverberation time (RT60) at different frequencies to identify where acoustic treatment is needed
Identify modal resonances — the specific low frequencies that build up and decay slowly in a room
Generate waterfall plots and spectrogram views to visualise how energy decays over time at each frequency
Export EQ correction curves for use in parametric equalisers to flatten a room's measured response
How to learn it
Learning Resources
REW's own Help documentation at roomeqwizard.com — detailed and accurate
YouTube: Home Studio Simplified and GIK Acoustics have practical REW measurement tutorials
Measure your own room with a measurement microphone (UMIK-1 or similar) — REW's value only becomes real when you see your own room's problems on screen
Pro Tip
A calibrated measurement microphone is essential — your regular condenser will not give accurate low-frequency data. The MiniDSP UMIK-1 (~$75) is the standard entry-level choice and REW has direct calibration file support for it.
Skills that use this tool
Roles that use this tool