Room EQ Wizard or REW is a Java application used to measure and analyze room modal resonances and loudspeaker responses. It is packed with advanced tools to generate test signals; measure Sound Pressure Level (SPL); measure impulse and frequency responses; generate group delays, phases and spectral decay plots; generate real-time analyzer (RTA); waterfalls and energy-time curves; display equalizer responses; calculate reverberation times; and automatic adjustments of settings of parametric equalizers, to counter effects of room modes while adjusting responses to suit targets.
REW is a program package used to measure transfer functions of acoustic displays and systems in order to correspond phase, frequency, impulse responses, and a variety of quantities obtained from them. It is able to grasp signals creating acoustic measurements of recorded sounds from a microphone or SPL meter. The soundcard measures the electrical level at its input.
A sweep signal is sent towards the source, which begins at a lower frequency until it moves one step higher. Once the sound is captured through a microphone, analysis begins. The Fast Fourier Transform (FFT) process is formed to calculate individual frequencies through their phases and amplitudes. With this application, users can optimize the acoustics of any space and determine the best location for speakers for a studio or home theater setup.