REW

Features in detail

• Free!
• Frequency response and distortion measurement using logarithmically swept sine signals for fast, accurate analysis of room acoustics and audio performance
• Measure using USB measurement microphone, analog measurement microphone or SPL meter
• Options to use a loopback connection or another speaker as a timing reference
• Offline measurement mode allowing responses to be generated from imported sweep recordings
• Frequency response and distortion (THD, IMD, TD+N) measurement using stepped sine at up to 96 points per octave
• Real Time Analyser with up to 1/48th octave resolution
• Signal Generator offering:
  • sine waves (optionally including harmonics with level and phase control)
  • Square waves
  • Sawtooth
  • Dual tone signals
  • Triple tone signals
  • Multitone signals
  • Tone bursts
  • CEA-2010 tone bursts
  • Linear and logarithmic sine sweeps
  • Random pink noise (full range, speaker calibration, sub calibration, CEA-2034, fractional octave and custom filtered)
  • Random white noise
  • Periodic pink and white noise (full range, speaker calibration, sub calibration, fractional octave and custom filtered)
  • Export of signals to WAV files
• Sound level meter with full integrating functionality including equivalent sound level and sound exposure level; mic/meter and soundcard calibration corrections applied; A, C or Z weighting
• Two channel oscilloscope with a math channel
• Spectral decay plots, waterfalls (Fourier and Burst Decay) and spectrograms (Fourier, Burst Decay and wavelet)
• Impulse response, step response and energy-time curves
• Reverberation times derived in accordance with ISO 3382 in octave or one-third octave bands with results for Early Decay time (EDT), T20, T30 and an optimal fit RT60 figure
• RT60 Decay plot using frequency domain analysis to provide decay data at much higher resolution and with narrower octave fractions than is possible with classical RT60 analysis
• Clarity and definition parameters C50, C80 and D50 plus centre time Ts
• Impulse response can be displayed with octave or one-third octave filters applied
• Frequency-dependent windowing of impulse response
• Harmonic and intermodulation distortion measurement including harmonic phase
• Phase & Group Delay (measured, minimum and excess)
• Phase wrap/unwrap
• Minimum phase response generation
• Impedance measurement including Equivalent Peak Dissipation Resistance (EPDR) plot, component model for inductor and capacitor measurements
• Thiele-Small parameter calculation from sealed volume, added mass or dual added mass impedance measurements
• Impulse Response delay calculation and adjustment
• Clock rate difference detection and correction when input and output are on separate devices
• Measurement arithmetic functions, add/subtract/multiply/divide/merge measurement
• RMS average, vector average and dB average of sets of measurements
• Equaliser entries for the Behringer DSP1124P/FBQ1000, FBQ2496 and DCX2496, QSC DSP-30, Crown USM 810, MiniDSP, ADA, Emotiva UMC-200/XMC-1/RMC-1/RMC-1L/XMC-2, waveFLEX DSP A8, Xilica XP2040, Anti-Mode 2.0 Dual Core, Rockford Fosgate 3Sixty.3, rePhase, Outlaw Audio Model 976, StormAudio, JL Audio TwK-88, Elder Audio TimeZero2.6D/4.8D, d&b audiotechnik tuning filters, CamillaDSP, Hypex Input EQ, JRULTR SubwooferEQ, Mosconi Channel EQ (9-band) and Main EQ (30-band), Grace Design m908
• Support for the Dutch&Dutch 8c eq features, including support for measuring using sweep signals generated by the speakers
• A configurable equaliser entry offering a selection of Q definitions
• Automatic identification of peaks in the response, automatic assignment of EQ filters to peaks and optimisation of filter parameters to counter the peaks and track a desired target response
• Waterfalls of predicted results of EQ can be viewed in the EQ panel and can update live as filter settings are adjusted
• Room resonance analysis to determine the frequencies and decay times of modal resonances with pole-zero plots of the response and any filters applied
• "Modal" filter setting provided for parametric EQ filters to aid in correcting modal decay
• Room Simulator supporting up to 8 subwoofers
• Frequency response import from and export to text files
• Impulse response import from WAV or AIFF files
• Export impulse responses of measurement or filter settings to WAV files
• Compensation for C-weighting when using an external SPL meter as the input, calibration files can be loaded for soundcard and microphone or SPL meter
• ASIO support
• Comprehensive help files within the application and on-line

Pro upgrade features

• Multi-input capture, allowing REW to capture multiple inputs simultaneously for measurement or for the RTA
• Measurements made with multi-input capture show an rms average of all the captured channel magnitudes with an underlay showing the span of the individual channels
• When using the miniDSP UMIK-X averages can be produced for each UMA4 mic array
• Individual measurements for each channel can be captured at the same time as the average
• Each input can have its own calibration file
• Individual weighting for each input to the average and option to align SPL before averaging. Weighting and alignment can also be adjusted after capture
• RTA measurements with multi-input capture show the rms average of the input channel magnitudes and up to 16 individual input traces simultaneously
• If only two inputs are selected for a multi-input RTA measurement distortion and levels can be shown individually for each and stepped sine measurements can be made for both inputs simultaneously
• Individual SPL metering for the first four inputs, level metering for up to 16 inputs