Sound Level

Standard 1/2 inch Free Field or Random Incidence Microphone Integrated Preamplifier Collar to Eliminate Reflections Class 1 sound measurements to the latest international standards Environmental noise assessment and monitoring Reverberation time measurement and building acoustics Tonality Occupational noise evaluation IEC 61672-1:2013, ANSI S1.4-2014 Class 1 integrating sound level meter Real-time frequency analysis in 1/1 and 1/3 octave bands, compliant with IEC 61260:2001 and ANSI S1.11-2004 Class 1 Large, high-resolution screen, easily readable in bright sunlight Robust battery life (24 hours...

The Larson Davis Model 831 Class 1 Sound Level Meter, with its high definition display, is extremely versatile, performing the functions of several instruments. It puts the combined features of a precision Class 1 sound level meter, environmental noise analyzer, personal noise dosimeter, and a real-time frequency analyzer in the palm of your hand. The Model 831 is a fifth generation Larson Davis sound level meter, designed for simple, singlehanded operation, yet is fully featured, smart and versatile with an ever expanding firmware platform. The design of the Model 831 was based on countless...

Considered Every Design Element Keyboard Features: flight operation Much care was taken when designing the Model 831 keyboard. To reduce extraneous noise, the keys are manufactured of silicone to eliminate audible "clicks". In addition, the ON/OFF button is slightly recessed to avoid accidental power off. Together with the backlit display, the illuminated keyboard permits nightly operation indoors as well as outdoors. Finally, a raised thumbrest allows for careful positioning during ^eCeSSed Pother KeyAoafd iS Ae/ot*j Screen *loSe Cone deftedts Sound t^weS - (Wording ■Xloustic reflections Tofjer...

Material Features: When selecting manufacturing materials, the day-to-day operation for users was taken into account. Advanced sound level meters like Model 831 are often used outside. The display with high readability in all lighting conditions is protected by a scratch resistant cover. A high impact plastic housing supports and safeguards the instrument for normal use. Access Features: The large battery access panel allows for easy exchange of batteries. Extra connections are grouped at the bottom of the instrument with PC control and power supply combined via a single cable. Single-handed...

Standard Features When performing noise surveys, it is important to have a fully capable sound level meter at your fingertips to capture all of the essential data. How many times have you brought along additional equipment to log information such as GPS location, temperature, wind speed, and other environmental parameters? Then, how much time did you spend after the test merging that non-acoustic data into a report? Have you ever lost your measurement notes, or worse, forgot to log the information properly and then had to either go back and reacquire the data altogether or simply not report it?...

The Larson Davis Model 831 provides an ANY LEVEL feature to preview and review acquired sound field measurements utilizing multiple time weightings (Slow, Fast & Impulsive) and frequency weightings (A, C &Z). This feature allows the operator to easily view and acquire measurement data with the desired settings and ensures the correct values are measured. With the 831 -LOG option all of the various measurement parameters are available and can simply be selected for storage and download. Pre-selected detector and frequency weighting are used to determine the metric sampled for statistical and event...

Normalized Spectrum Live Display of Triggers During Measurement 831-OB3 Frequency Analysis firmware allows the user to compare the frequency content of various measurements using the Normalized Spectrum function. Inverse A and C weighting filters can be applied, as well as user defined curves to current measurements and graph them relative to each other. For example, when comparing the noise signatures of various machines, a reference measurement can be saved such that subsequent measurements can easily be compared. Fig. 3 Normalized Spectrum Display Two RMS and Three Peak Threshold Triggers...

Voice Recorder The Model 831 allows for annotative noise measurements with a voice memo via a headset plugged into the AC/DC output jack or directly through the condenser microphone. Informa- tion can be played back through a headset directly connected to the in- strument or by downloading the data Voice Recorder To further annotate data in the field, the Model 831 allows the user to Markers which are easily accessed through the main measurement screen. For example, during a traffic noise measurement, markers such as queued such that they are quickly ready to identify certain events. Time history...

Weather Measurements The Model 831 can be configured to log weather parameter data in the Time History along with all of the normal acoustic parameters at rates up to 1 sps (sample per second). A wide range of meteorological parameters are available including wind speed, wind direction, temperature, humidity and rain fall. Combined Meteorological Unit (SEN031 Vaisala WXT520) Measurement Method Connectivity Measured Parameters Digitized sensors with ultrasonic wind sensors over serial port to USB USB to Model 831 or 831-INT (-ET) Wind speed and direction, temperature, relative humidity, barometric...

Noise map created using web-based GPS mapping Global Positioning System (GPS) Commonly, users want the ability to use GPS to log the location for each measurement, which is very beneficial when performing environmental noise surveys that require multiple points around large buildings or when mapping noise along a roadway. To meet this need, every Model 831 Sound Level Meter is equipped with firmware to decode and log GPS position information from an optional external GPS antenna (GPS001). When enabled, the GPS will log in position automatically at the beginning of each measurement run (831-ELA)....