Model 831 Reverberation Time Software Measurement and Calculation of Reverberation Time using the Integrated Impulse Response or Interrupted Noise Methods with 831-RT Firmware. Highlights I T20 and T30 measurements according to ISO 3382-2:2008 and ASTM E2235-04 1/1 and 1/3 octave band analysis Supports Integrated Impulse Response and Interrupted Noise excitation methods Built-in pink and white noise generator Automated trigger Display of RT spectrum, individual and ensemble decays Quality indicators to ISO 3382-2 Field upgradable – requires no other options Reverberation time Absorption coefficient Room acoustics Architectural acoustics Whether for performance venues, architectural measurements or work-place acoustics, reverberation time is a key parameter for characterizing a room. A long reverberation time can make speech less intelligible and music can become garbled. Too short a reverberation time can muffle speech and make a room sound “thin”. The 831-RT firmware option adds reverberation measurement and calculation functionality to the Model 831 sound level meter. 831-RT firmware was designed with simplicity in mind yet complies with the latest ISO 3382-2 and ASTM E2235-04 measurement standards. It supports both the Integrated Impulse Response and Interrupted Noise excitation methods and includes an automated trigger to easily control the measurement. The on-board signal generator provides a pink or white noise source for optional amplifiers and omni-directional or façade speakers via the AC/DC output connector on the Model 831. The user can display an individual RT spectrum and discard those with erroneous data. The spectra from multiple positions are ensemble averaged to display an overall RT60 calculation. A full battery of quality indicators supports the validation of measurements. Additionally, grading of the measurement according to ISO 3382-2 indicates whether sufficient positions (microphone-source combinations) have been acquired to obtain the expected grade: survey, engineering or precision. Larson Davis

831-RT with Model 831 complies with following standards IS03382-1:2006 Measurement of Room Acoustic Parameters Part 1: Performance Rooms S03382-22008 Measurement of Room Acoustic Parameters Part 2: Reverberation Time in Ordinary Rooms ASTM E2235 (2004) Standard Test Method for Determination of Decay Rates of Use in Sound nsulation Test Methods EC 61672-1:2002 Class 1 Electroacoustics - Sound level meters EC 61260-1:2003 Class 0 Electroacoustics - Octave-band and fractional-octave-band filters Reverberation Time mpulse Excitation using reverse time integration (Schroeder method] nterrupted noise...