Model 831 Brochure
Standard 1/2 inch
Free Field or
Random Incidence
Integrated Preamplifier
Collar to Eliminate Reflections
Class 1 sound measurements to the
latest international standards
Environmental noise assessment and
Reverberation time measurement and
building acoustics
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 on 4 X AA
Lithium batteries)
Simplified system and measurement set-up
through a “mobile phone like” interface
Lightweight, ergonometric design
Soft keypad for 1-handed operation
Standard USB interface
Dynamic range in excess of 120 dB
Logging of broadband and spectral data to
obtain time, measurement and event
histories on the instrument
Sound recording in .wav format for event,
manual or time-based trigger
Utility software included for set-up,
archiving, export and reporting
Supplied with heavy-duty Pelican®
carrying case
HPD selection
Noise reduction validation
Product quality control
NVH correlation
In-Situ sound power measurements
Code enforcement
Large High Resolution
One-button Access to
Measurement Set-up
Run/Pause Control
Model 831 Layout
Display Navigation
Dual Purpose Start/Stop
Back-lit Navigational
Reset/Clear Memory
System Set-up Access
Recessed On/Off Button
Headphone Jack/Noise
Source Control
USB Host (Thumb Drive
Storage, GPS Receiver)
USB Power
Master Power Toggle
The Pelican trademark is a registered trademark
of Pelican Products, Inc.
Larson Davis | Toll-Free in USA 888.258.3222 | Phone: 716.926.8243 |
Multi-function Connector
(External Power,
Weather Sensor Input)
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 inputs from customers. It expands upon the Larson Davis tradition
of delivering value, innovation and function in a rugged, single-handed,
expandable package and is backed by a 2-year factory warranty, 24-hour
application support and accredited factory service/calibration.
The Model 831 Standard Features:
IEC 61672-1:2013, ANSI S1.4-2014 Class 1 integrating sound
level meter
Voice Annotation
User-programmable run modes
Six user-selectable statistics (Ln)
Threshold exceedance data
Community noise calculations (Lden, CNEL)
GPS support
Back erase functionality
Normalized spectrum
User-selectable screen layout and lockable set-up protection
Remote access and field upgradable
Wide variety of non-proprietary powering options including –
4XAA internal batteries, AC, USB and external batteries
Model 831 Firmware Options:
1/1 and 1/3, Class 1, octave band spectral analysis
Industrial Hygiene or personal noise dosimetry
Time history logging at periods from 20 ms to 24 hrs
Fast time history logging at 2.5, 5 or 10 ms periods
Automatic event detection, event history, and measurement history
(1 min to 99 hour intervals) combine with 831-LOG for event time
history and 831-SR for event sound recording
Sound Recording to .wav files at 8, 16, 24 or 48 kHz
Reverberation time measurement, computation and display
Fast Fourier Transform up to 6400 lines
Advanced digital communications via cellular modem
Measurement History and Sound Recording
Supported PC Software:
SLM Utility-G4 – PC software supplied with the Model 831
that supports full sound level meter control, in the field
firmware and option upgrades, data export to Excel®, and
includes an integrated “Screen Grabber” to display the SLM
screen live on a PC
DNA – the analysis, post-processing and reporting tool for
sound and vibration measurements. DNA delivers enhanced
analysis capability, sound playback and graphical reporting.
Graphs can be annotated and shared amongst multiple users
using DNA reader software.
Software Development Kit (SDK) – toolkit for developing
custom applications in MS Windows® or Linux for the Model 831
3rd Party – the Model 831 has been integrated into various 3rd
party software packages including software for airport noise
The Model 831 offers a complete solution for noise measurement.
Whether in the office or in the field, the Model 831 can handle your
sound measurement needs.
Excel is a registered trademark of Microsoft Corporation in the United States
and/or other countries.
Larson Davis | Toll-Free in USA 888.258.3222 | Phone: 716.926.8243 |
…We Carefully
Considered Every
Design Element
Keyboard Features:
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
Avoid Acoustic Reflections:
To reduce noise reflections further, a noise cone was added between the
preamplifier and the sound level meter body. The keypad is situated
below the screen for ease of use and is slightly lower in height which
positions the user’s hand lower on the body allowing a free flow of
acoustic waves. The preamplifier connection, the bulkier head, and the
lowered keypad all contribute to the Model 831 Class 1 designation.
Larson Davis | Toll-Free in USA 888.258.3222 | Phone: 716.926.8243 |
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 Operation:
To reduce acoustic reflections during measurement, Model 831 was
designed with single-handed operation in mind. The soft grips combined
with the overall inverted cone shape allow the meter to easily fit in the
hand, without permanent finger pressure or user attention. For extra
security a lanyard is provided as a standard accessory.
Larson Davis | Toll-Free in USA 888.258.3222 | Phone: 716.926.8243 |
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? At Larson Davis, we recognize the value
of measuring non-acoustic parameters in parallel with the acoustic data. The
Model 831 firmware allows you to connect a variety of external sensors to log
these non-acoustic parameters.
Extended Power Operation
Model EPS031
Fiberglass NMS enclosure (AC power)
A variety of powering options allows for flexibility when out in the field. There
is no need to worry about proprietary batteries, cables, etc. since most power
options are “off-the-shelf items”. Great care was taken during the design of
the Model 831 to ensure low power consumption, further extending measurement time. With (4) Lithium AA batteries, up to 24 hours of 1 second LAeq
with 1/3 octave data can be measured.
Options include:
AA batteries: Alkaline, NiMH rechargeable or 1.5V Lithium
USB power from a universal AC power supply (PSA027), a PC or a
powered USB hub
12 VDC from a DC power adaptor, 12 VDC battery, or car power
When using 12 VDC, the Model 831 can sense a low voltage condition and shut
itself down automatically then restart automatically upon power restoration to
protect external batteries from damage due to over-discharge.
Larson Davis | Toll-Free in USA 888.258.3222 | Phone: 716.926.8243 |
Available Broadband Metrics
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 data.
The Model 831 has six (6) measurement control modes to accommodate
a variety of field situations.
MANUAL – typically used for walk-around surveys. Ideally
used with the Measurement History (MH) to give a quick
overview of the averages, the min-max values, and store
multiple measurements into a single file.
TIMED STOP – operates for a specified period of time
CONTINUOUS – typically used for longer term monitoring, it
allows storage of data files daily or even multiple times during
the day. In this mode the Model 831 will start automatically
upon powering. This is required for instances of power failure
in remote locations.
STOP WHEN STABLE – typically used to assess workplace
noise exposure, it stops when the LAeq is stabilized in a
narrow range
SINGLE BLOCK – a start and stop timer controls the sound
data acquisition
MULTI-BLOCK – three separate time periods, of which one
can cross the dateline
LwF, Min
LwI, Min
LwF, Max
LwI, Max
Six Different Run Modes
Fig. 1
ANY LEVEL allows the display of all
acoustic parameters simultaneously
NoiseTutor Environmental Noise Monitoring System
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Normalized Spectrum
Fig. 2
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
Fig. 4
Another standard feature of the
Model 831 is the ability to define up
to two (2) RMS and three (3) Peak
threshold levels. During operation,
Model 831 will count the number of
threshold exceedances as well as the
cumulative time of exceedance. This
information is available real-time on
the instrument display as well as
included on any measurement files
transferred to software. This is an
ideal way to keep track of limit and
action values according to EU
Directive 2003/10/EC.
Trigger Levels
Back Erase
Simple transient noises such as an
ambulance siren or dog bark can
erroneously contribute to an outdoor
measurement. The Model 831 includes
a Back Erase feature allowing for the
removal of the last 5 or 10 seconds of a
measurement and recalculate the
measurement parameters automatically.
To ensure proper bookkeeping, the
data is annotated so it can easily be
identified post test.
Fig. 5
Back Erase Display
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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. Information can be played back through a
headset directly connected to the instrument or by downloading the data
file to a PC.
Fig. 6
Voice Recorder
Ten Annotation Markers
To further annotate data in the field,
the Model 831 allows the user to
enter up to ten (10) user-defined
Markers which are easily accessed
through the main measurement
screen. For example, during a traffic
noise measurement, markers such as
“Truck” or “Motorcycle” can be
queued such that they are quickly
ready to identify certain events. Time
history data is then tagged with this
Marker for ease of reporting. When
equipped with the optional 831-SR
Sound Recording firmware, the
Model 831 will also automatically
take a .wav file sound recording when
a Marker is engaged.
Fig. 7
Model 831 with optional 831-SR Sound
Recording Firmware. One screen
access to manual sound recordings and
exceedance markers.
User-selectable Screen Layout
The powerful Model 831 user interface can be tailored for a wide-variety of
end users. While the acoustical consultant may like to see all data
parameters, a code enforcement officer may simply like to read the Leq or
Peak dB level. In addition, the sound level meter may be utilized by untrained
personnel who are unfamiliar with the set-up of the instrument. In this
situation, the Model 831 provides a lock feature so that set-up parameters
cannot be modified without entering a security code. Modifying the user
interface of the Model 831 is easily done via the keypad or SLM Utility G4
Software. Various set-ups and configurations can be created within G4 and
transferred to the sound level meter such that they are easily accessible.
Fig. 8
Customizing Model 831 Instrument Displays
utilizing SLM Utility-G4 Software
Larson Davis | Toll-Free in USA 888.258.3222 | Phone: 716.926.8243 |
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
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 pressure, rain fall and hail
Fig. 9
Model 831-INT Docking
Station – Configuration
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Sierra Wireless
LS300 Gateway
Vaisala WXT520 (SEN031)
USB to Model 831
Fig. 10
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). In addition, the GPS signal also includes a highly accurate clock that the Model 831 can use
to automatically update its internal clock as needed. Once the data is downloaded to a PC, the location
information can be easily imported into mapping software to create, in seconds, a very powerful report
showing exactly where noise measurements were made.
Location and Timestamp with GPS001
Time Synchronization
Automatically performed with daily auto-store
Latitude, longitude and altitude with measurement history
Fig. 11
Export the “Measurement History” tab directly into a web-based GPS mapping software (shown above). This tool
will retrieve the appropriate map and add the acoustic parameters to the map automatically.
Model GPS001
Used with permission from Microsoft. Excel is a registered
trademark of Microsoft Corporation in the United States
and/or other countries.
Larson Davis | Toll-Free in USA 888.258.3222 | Phone: 716.926.8243 |
Model 831 Options:
Octave Band Analysis (831-OB3)
Fig. 12
Fig. 13
1/1 Octave Display
1/3 Octave Display
In many applications, it is important to acquire both the broadband level and
spectral content of noise data. With spectral information, the source and
content of the measured overall level can be better understood. Constant
percentage bandwidth filters (1/1 or 1/3 octave) best approximate human
perception to sound. Option 831-OB3 firmware enables simultaneous real
time measurement of 1/1 and 1/3 octave Leq, Lmax, Lmin along with all the
ANY LEVEL broadband parameters. Option 831-OB3 is compliant with IEC
61260:2001 Class 1 and ANSI S1.11-2004 Class 1 standards and covers the
entire frequency range of human hearing: 6.3 Hz to 20 kHz for 1/3 octave
bands. When 831-OB3 is combined with Time History Logging (831-LOG) or
Automatic Event Detection and Event History (831-ELA) it is possible to review the frequency content of logged data or specific events.
Fig. 14 Events Extracted from Noisy Data
Fig. 15
Spectrogram of
Events with High
Frequency Noise
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Industrial Hygiene (831-IH)
The Model 831 is available with two (2) virtual noise dosimeters compliant with ANSI S1.25 and
IEC 61252:2001, each with programmable threshold levels. This is very convenient when performing
worker noise exposure assessment when coupled with the 1/1 octave band spectral analysis for
hearing protection device selection. Typically, the characteristics of the hearing protectors are stored
as one of the four reference curves on the Model 831 for easy on-site “what-if” measurements.
Logging (831-LOG) & Fast Logging (831-FST)
Fig. 16
DNA Software Time
History and Hourly
Interval Graph with
Color Spectrogram
The Model 831 can be used to record the evolution of sound pressure level over time
as a Time History (TH). The Time History is then used to profile the observation period,
which can vary from a couple of seconds to continuous monitoring.
Larson Davis has enhanced the versatility of the Model 831 Sound Level Meter with
the addition of Time History Logging Firmware (831-LOG). Users can pre-select from
logging periods as small as 20 ms to a full 24 hrs. With time periods greater than or
equal to 100 ms, up to 58 selectable parameters can be chosen. Selections consist
of familiar acoustic metrics as well as non-acoustic metrics, such as battery condition,
outdoor microphone performance and meteorological data (831-WTHR).
Special acquisition circumstances may require the user to acquire time-based data
swifter than 20 ms. For these occasions, Larson Davis offers 831-FST firmware, which
adds the additional sampling rate options of 2.5, 5, and 10 ms.
Fig. 17
Time History Parameter Selection in SLM Utility-G3
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Measurement History (831-ELA)
While time histories are typically logged at one sample per second, it is
convenient to view longer term averages of measurement data to more
easily ascertain trends, i.e. 10 minute or one hour averages of various noise
parameters. The 831-ELA firmware enables Measurement History (MH)
which logs parameters similar to the Time History (TH) yet looks at the
average, minimum and maximum over the selected interval time. MH and
TH can run in parallel or independently.
MH records are time-based when run mode = continuous, but in other
run modes like manual, they are not. One of the benefits of MH
history is the ability to make a series of smaller measurements. MH
records and combines measurements automatically into a single
composite measurement and puts everything into one file.
When the Model 831 is set to “Manual Run” mode, MH history can be
used to construct a noise survey. Data for each measurement or location
is saved individually and may include the Leq, Lmax, Lmin, SPL, and
statistical distribution of the SPL (Ln).
MH records are available for easy review on the Model 831. The current
measurement is visible on the “Current” display tab, while completed
measurements can be browsed in the “Measurements” tab. When
combined with 831-LOG, the time history detail of each measurement can
be viewed quickly using keypad shortcuts. Finally, an automated sound
recording at the beginning of each measurement can be achieved with 831SR firmware.
Fig. 18 Current Measurement
Fig. 19 Measurement History
Automatic Event Detection and Event History (831-ELA)
Summary Display
In the Model 831 events are defined as either:
Exceedance of a fixed threshold level for a minimum duration
Exceedance of a dynamic threshold level for a minimum duration
External trigger set by the digital input signal
Fig. 20 Event Definition on the Model 831
The Model 831 includes basic exceedance logging functionality (see
“Threshold Triggers”on page 8). However, only the number of exceedances
and cumulative time above threshold values is provided. With 831-ELA
firmware, you are able to define the attributes of an event including threshold level, duration and hysteresis. An event is considered “Valid” when it
meets these criteria and ends when the SPL drops below the threshold level
for a specific period of time (Continuation Period). The user is provided triggering status updates via triggering icon graphics, helping to identify event
progression and qualification (see graph above).
The “Event” tab contains detailed information on each event including:
Time and duration of Event
Leq, Lmin, Lmax and Peak SPL
Frequency analysis of event (with 831-OB3)
Sound recording in .wav format for source characterization
(with 831-SR)
Event time history (with 831-LOG). Time history period can be
different than that used in overall TH measurement.
Fig. 21 DNA Software – TH with embedded .wav files on event, color
spectrogram, L95 and 1/3 octave frequency analysis
A “Dynamic” trigger method can
also be selected in the Model 831.
The dynamic trigger is set to trigger
when L85, L90 or L95 is exceeded
by a predetermined number of
decibels. A rise time can also be
specified to determine how quickly
the meter responds to changes in
the background noise level. By
utilizing the dynamic trigger, the
number of false triggers is reduced
and events (significant noise above
background level) are better
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Fig. 22 Event Detection Display
on the Model 831
Hear the Sound Being Measured
Measuring sound levels is a well-accepted way to objectively quantify
the noise radiated by a product in an environmental survey. But a sound
pressure level or octave data only provides part of the overall acoustic
picture. How many times were you asked “are you sure that the spike in
the data is actually the noise of the product or the actual environmental
event of interest?” Rather than rely simply on the ‘objective’ data why
not record a sample of the sound to truly determine if that elevated noise
level was a police car driving past with its sirens on or a noisy dog barking
at the letter carrier.
When recording raw time samples for playback, users can add the 831-SR
firmware option. This option allows for high fidelity recordings up to
48 kHz sampling with the Model 831 either manually or automatically,
based on an array of triggering options.
Option 831-SR Features:
User-initiated Recordings:
Manual Sound Recording - User-controlled recording
duration, acquired during operation, up to 48 kHz
Marker-based Sound Recording - User-initiated with userdefined duration, acquired during operation, up to 48 kHz
Automatic Recording Mode:
When the 831-SR option is combined with other advanced logging
functionality in the Model 831, it is possible to start and stop recordings
based on a number of advanced measurement events. This allows the
user to only record sounds associated with specific noises as they occur
rather than recording many hours of data and having to ‘find’ these events
after the fact in post processing software.
Option 831-ELA Recordings:
Event History Sound Recordings - Acquired upon
events meeting preset conditions with fixed or dynamic
triggering available
n Measurement History Sound Recordings - Automated
sound recording at the beginning of each Measurement History
Note: Event & Measurement Sound Recordings can be enabled at the
same time.
These recordings can then be downloaded to a PC and stored as .wav
files using the included SLM Utility-G4 software or the DNA advanced
post processing and reporting tool.
Typical Model 831 Sound Level Meter Ranges
(when using a microphone with 50 mV/Pa sensitivity)
Instrument Gain
0 dB
20 dB
Peak Overload Level
143 dB
110 dB
123 dB
90 dB
Lower Level of A/D Range
50 dB
17 dB
30 dB
-7 dB
Instrument Noise Floor
23 dB
23 dB
21 dB
21 dB
Sound Recording Range
50 - 143 dB
23 - 110 dB
30 - 123 dB
21 - 90 dB
Fig. 23
Fig. 24
A recording icon will appear on the
Model 831 display
when recordings
are being made.
Event Indication Display on the
Model 831
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Reverberation Time (831-RT)
Reverberation times are used in multiple architectural acoustics applications ranging
from simple experimental reverberation time determination for room performance,
to calculating absorption coefficients for material performance. Most of the time,
these measurements are dictated by various international standards.
Fig. 25
RT Displays of Decay Curves
Model 831 measures the decays and then computes the reverberation time according
to ISO 3382-2 or ASTM 2235-04 standards. When using the Interrupted Noise
method, the Model 831 not only triggers the data acquisition, but its built-in Noise
Generator can be used to drive the omni-directional sound source. Recent trends
show that the Integrated Impulse method is gaining popularity and Model 831 handles
the acquisition of the decays and the subsequent T20 or T30 calculations completely
and with ease.
While the use of 1/3 octave bands is the most common method on the Model 831,
the user can elect to work either with 1/3 octaves or full octave bands.
Helping the user in the field assess his measurement results the Model 831 computes
the decay times automatically, shows the T20 and T30 spectra superimposed,
computes seven (7) quality indicators per frequency as well as grades the
measurement data. All these indicators are immediately available saving considerable
Easy-to-read screen and keyboard indicators help guide the user through the
measurement. For example, a flashing red LED on the Model 831 indicates to the
user when they need to create the impulsive noise, for example, with a starter pistol
or a balloon.
Fig. 26
The resulting data and decays can be exported to the SLM Utility-G4 or can be
processed further in DNA for reverberation time, absorption coefficients or sound
insulation calculations. Using DNA software, a full array of building acoustic
measurements are possible as defined in ISO 10140, 140, 717 and ASTM standards.
Quality and Measurement Grade Indicators
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Fig. 27
FFT Max-tracking on Model 831
Fast Fourier Transform Analysis (831-FFT)
Fig. 28
DNA Software FFT-spectrogram
of Stone-cutting Operation
When a frequency resolution greater than 1/3 octave band spectral analysis is needed, the Model
831-FFT frequency analysis is the ideal solution. The Fast Fourier Transform (FFT) algorithm is
implemented in the Model 831 for precision spectral analysis of acoustic signals. By utilizing a variety
of frequency span and resolution settings, FFT acquisition settings can be adjusted to tune into specific
acoustic and vibration phenomena.
The Model 831-FFT has three (3) operational modes serving different applications. The “Count” mode
accumulates the average spectrum and maximum for a fixed number of FFT spectra. The “Timed” mode
repeats the count mode for a given period of time and accumulates the spectra in a history. The “Timed”
mode is best suited for transient signals, while the “Manual” mode is typically used for steady state
measurements. In Manual mode, the number of averages is open and each Start-Stop sequence adds
an entry to the history table.
Up to 6400 lines of resolution are available with the Model 831-FFT, allowing for detailed measurement analysis.
The FFT option has been further enhanced with the onboard computation of tonality as described in
ISO 1996-2 Annex C. Tone level, masking noise level, audibility and quality indicators are all automatically
computed and displayed in a simple to use interface that makes object measurement of tones in the field easy.
Fig. 29
Model 831 Tonality Calculation
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Data Navigation and Analysis Software (SWW-DNA)
Data Navigation and Analysis Software (SWW-DNA) is designed to analyze
and report environmental noise, worker exposure and architectural acoustic
measurements with an interactive graphical interface.
DNA and the Model 831 can be used in two ways: DNA retrieves files from
the Model 831 or DNA uses the Model 831 as a data acquisition front-end.
Remote access over modem or network
Interactive graphs with data: zoom, evaluate processing for events,
masking automated placement of speaker icon on time
history and running cursor with sound replay on TH linked
cursors over several graphs
Template based operation with customizable templates
A major differentiating concept of DNA is the principle of separation
of data and graphical layout. This allows for drag-and-drop
functionality of new data in the same layout. With many
environmental studies being similar in nature, this feature allows
for quick, professional looking reports.
Software Solutions
The Model 831 has numerous on-board capabilities, yet often further processing,
visualization or reporting needs exist. For this purpose the Model 831 can be used
as a portable instrument and retrieve the data, work as a data acquisition frontend, or in combination.
SLM Utility-G4
The SLM Utility-G4 program is an easy-to-use Windows® software for the Model
831 providing configuration set-up, data download and remote access. The
Screengrabber feature emulates the SLM screen on your PC, convenient for
presenting data stored on the Model 831 or for teaching classes. Measurement
set-ups can be stored on the PC and exchanged with one or more Model 831
sound level meters. Data can be downloaded into a PC and easily exported to
Excel® for further analysis. SLM Utility-G4 can simultaneously access multiple
831-based noise monitoring stations via USB, modem or Ethernet, which makes
managing multiple noise monitors simple and convenient.
Software Development Kit (831-SDK)
The Software Development Kit for the Model 831
interfaces smoothly and directly with Microsoft or
Linux programming environments supporting
Excel®, VBA, Visual C++ or C# programming
The SDK provides functionality to establish
connection and fully control the Model 831 over
USB, network or modem connections. File
download is supported and the SDK includes
documentation and software for extracting data
from files.
Because of a reliance upon JSON, the SDK
makes it easy to create modern, web based
applications with minimal effort.
Microsoft, Visual Studio and Excel are registered trademarks of Microsoft
Corporation in the United States and/or other countries.
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Model CAL200
Model CAL250
Model ADP021
1 inch – 1/4 inch
Calibration Adaptor
Model EPS2116
Environmental Shroud
Model ADP024
1/2 inch – 1/4 inch
Calibration Adaptor
Model WS001
1/4 inch Free Field
1/4 inch Random Incidence
1/4 inch Pressure
Model PRM2103-FF
Microphone & Preamplifier
Model TRP003
Model ADP074
ICP® Sensor Adaptor
Model TRP001
Model PRM831
Model PRN003
Model BAS001
Speaker Source
AA Alkaline
Model SEN031
Weather Station CBL167 &
AA e-Lithium
Model GPS001
Model BAS002
SLM Utility-G4
Model EPS036/7
Environmental Case
Model PRM2103-FF
Microphone & Preamplifier
1/2 inch Free Field
1/2 inch Random Incidence
1/2 inch Pressure
Model ADP043
1/2 inch – 1/4 inch Preamp Adaptor
Model BAT011
12V Battery
Model EPS2116
Environmental Shroud
Model PSA029
AC Adaptor
Model 831-INT(-ET)
Docking Station
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Model 831 Standards, Features & Specifications
Standards Met by Model 831
The Model 831 meets the specifications of the following standards:
General Specifications
Sound Level Meter Standards
Reference level range
114.0 dB re. 20 μPa
Reference frequency
1000 Hz
Reference direction
0° is perpendicular to the microphone diaphragm
Reference level
IEC61672-1 Ed. 2.0 (2013-09) Class 1, Group X
IEC60651 Ed 1.2 (2001) plus Amendment 1 (1993-02) and Amendment 2 (2000-10) Type 1, Group X
IEC60804 (2000-10) Type 1, Group X
ANSI S1.4-2014 Type 1
Single large range for SLM Normal for OBA option, Gain 0 dB
≤ ± 0.5 dB error between +14 to +122 °F (-10 to 50 °C)
Octave Filter Standards (Option 831- OB3)
Storage temperature
-4 to 158 °F (-20 to 70 °C)
IEC61260 Ed. 1.0 (1995-08) plus Amendment 1 (2001-09), 1/1 and 1/3 octave bands, Class 1, Group X, all filters
≤ ± 0.5 dB error from 30% to 90% relative humidity at 104 °F (40 °C)
ANSI S1.11-2004 Class 1
Equivalent Microphone Impedance
12 pF for Larson Davis 1/2 in microphone
Personal Noise Dosimeter Standards (Option 831-IH)
Range Level Error (OBA option)
IEC61252 Ed. 1.1 (2002-03) Type 1
Digital Display Update Rate
Effect of an Extension Cable
≤ ± 0.1 dB relative to the reference range
Four times per second (0.25 sec between updates). First display indication is
available 0.25 seconds after initiation of a measurement.
None (up to 200 ft or 61 m with EXCxxx cable)
Safety Requirements for Electrical Equipment for Measurement, Control and Laboratory Use
Electrostatic Discharges
The instrument is not adversely affected by electrostatic discharges
2006/95/EC Low Voltage Safety Directive
Extended Weather Options
-40 to +158 ºF (-40 to +70 ºC) operation with CER-831-E
IEC 61010-1 Ed. 3.0 (2010-06)
Resolution Specifications
EMC Immunity and Emission
0.1 dB
2004/08/EC EMC Directive
IEC 61326-1 Ed. 2.0 (2012-07)
Elapsed time
0.1 second
IEC 61672-1 Ed. 2.0 (2013-09)
Real time clock
1 second
FCC Title 47 CRF Part 15, Class B
Through 31 Dec 2100
Model 831 General Features and Characteristics
Integration Time
Class 1 Precision Integrating Sound Level Meter with real-time 1/1 and 1/3 octave filters
Time Averaged Levels and Sound Exposure Levels (s)
Non-Volatile Memory
0.1 second
High contrast 1/8th VGA LCD display with white LED backlight; sunlight readable
Maximum with Daily Autostore Enabled
Icon-driven graphic user interface
Maximum with Daily Autostore Disabled
> 23 days with error < 0.5 dB
Soft rubber backlit keys
Dosimeter Metrics: TWA, Dose (s)
Large dynamic range
0.1 second
Time weightings: Slow, Fast, Impulse, Integration and Peak simultaneously (AnyData)
Frequency weightings: A, C, Z simultaneously (AnyData)
Ln Statistics
1/1 and 1/3 octave frequency analysis available
Number of selectable parameters
6 in xx.xx% format, visible on the Model 831
Voice message annotation and sound recording
Storage of Complete Table
0.1 dB Steps
Ln statistics (L0.01 through L99.9 available)
Spectral Statistics
Requires Octave Analysis option (831-OB3)
SLM Utility-G3 software available for set-up, control and high speed data download with export to Excel®
Multi-tasking processor allows measuring while viewing data or transferring data
Number of Markers
Data Secure feature saves data to permanent memory every minute
Prenamed Markers
5: Truck, Automobile, Motorcycle, Aircraft, Exclude
AC/DC outputs to recorder
Link Marker to Automatic Sound Recording
Yes, requires Sound Recording option (831-SR)
Long battery life; > 16 hours continuous measurement
Back Erase
ANSI S1.25-1991 Class 1
Multiple language support: English, German, Italian, Spanish, Portuguese, Swedish, French & Turkish
Field-upgradable firmware: keeps instrument current with the latest measurement features
Two-year limited warranty
Back Ease Time
5 or 10 seconds
Supported Modes
Measurement Control Modes
Sound Level Meter Specifications
Averaging (Integration method)
Linear or Exponential
Available Modes
RMS Time Weighting
Slow, Fast or Impulse
Timed Stop
Frequency Weightings
A, C or Z
Stop When Stable
Peak Detector Frequency Weighting
A, C or Z
0 dB or +20 dB
Exchange Rates
3, 4, 5, or 6 dB with optional 831-IH
Sample Rate
51,200 Hz
Peak Rise Time
30 µs
Manual Stop, Timed Stop, Stop when Stable, Continuous, Single Block
Timer, Daily Block Timer
Time in hh:mm:ss
Continuous Restart on Power Failure
Delta level in xx.x dB and time in hh:mm:ss
1, 2, 4, 6, 12, 24, 48, 96 or 144 files per day, automated file numbering
Automatic if powered by 12VDC
Single Block Timer
Start date and time to End data and time
Daily Block Timer
Up to 3 blocks with each start and end date, blocks can cross date line
Continuous with Daily Auto-Store
Clock Stability
Physical Characteristics
< 1 sec in 24 hours, at 75 ºF (+24 ºC)
Length with Microphone and Preamplifier
11.35 in
29.0 cm
Length, Instrument Body Only
8.8 in
22.4 cm
2.8 in
7.1 cm
Digital Voice Annotation
1.6 in
4.1 cm
Annotate Recordings
Use headset (ACC003) or measurement microphone
Weight with Batteries, No Preamplifer or Microphone
13.6 oz
390 g
Recording Sample Rate
8 ksps
Weight with Batteries, Preamplifer and Microphone
1.2 lb
550 g
Listening Options
On the Model 831 or using processing software for .wav files
< 10 sec in 30 days, at -40 to +158 ºF (-40 to +70 ºC)
Excel is a registered trademark of Microsoft Corporation in the
United States and/or other countries.
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AC/DC Output, Power Supply, Memory Retention,
Broadband Noise Level & Preamplifiers
Model 831 Preamplifier Specification (PRM831)
Frequency response with respect to the response at 1 kHz with 1 Vrms input and 12 pF equivalent microphone.
8 Hz to 16 Hz
+0.1, -0.2 dB
16 Hz to 100 kHz
+0.1, -0.1 dB
Lower -3 dB limit
< 1.5 Hz
0.1 dB (typical)
Input Impedance
10 G Ω / 0.16 pF
Output Impedance
50 Ω
Maximum Output
28 Vpp 143 dB peak for microphones with 50 mV/Pa sensitivity
Maximum Output Current
12 mA peak
Harmonic Distortion
< -70 dBC with 8 Vrms output at 1 kHz
Output Slew Rate
General Specifications (Continued)
Power Supply Voltage
AC/DC Output
2.5 mm (3/32 in), see CBL139 cable
AC Output Voltage Range
± 2.3 Vpeak maximum output, 0.5 mV to 1.6 Vrms sine
AC Output Recommended Load
Headset with ≥ 16 Ω speaker impedance
DC Output Voltage Scale
10 mV per dB, 0 V for 0 dB, 1 V for 100 dB
DC Output Frequency & Time Weighting
Follows SLM Settings: A, C or Z and S, F or I
Tee-off Preamplifier Signal Alternative
2 V per μs (typical)
Electronic Noise With 12 pF Equiva- 1.8 µV typical A-weighted (2.4 µV max)
lent Microphone
4.3 µV typical Flat 20 Hz to 20 kHz (5.0 µV max)
Use ADP015 and EXC006
DC Output Level
15 to 36 V
~1/2 power supply voltage
Power Supply Current
1.9 mA (typical)
Temperature Sensitivity
< ±0.05 dB from +14 to +176 °F (-40 to +80 °C)
Humidity Sensitivity
< ±0.05 dB from 0 to 90% RH, non-condensing at +122 °F (+50 °C)
Dimensions (D x L)
0.50 x 2.88 in (12.7 x 73 mm)
Microphone Thread
11.7 mm - 60 UNS (0.4606 in - 60 UNS)
Cable Driving Capability
Power Supply
The Model 831 SLM (10 Vrms output signal) to 20 kHz with 200 ft (61 m) cable
4-AA (LR6) NiMH, 1.5 V Lithium or Alkaline cells
(supplied with 2500 mAh NiMH)
Output Connector
All values are at 73 °F (23 °C), 50% RH, 35 V supply, 10 ft (3 m) cable
and equivalent microphone of 12 pF unless otherwise stated
Switchcraft TA5M (5-pin male)
Compatibility (to IEC61094-4)
Use with 1/2 in microphone, typical 50 mV/Pa sensitivity
External Power (5 V from USB)
USB Mini-B connector to
* USB interface from computer
* PSA029 AC to DC power adaptor
* USB Hub
* PSA031 12 VDC to USB adaptor
Model 831 with PRM831 and 377B02 Microphone
Operating Time on 1.5 V Lithium
Power through I/O connector: 10 to 15.5 VDC Use cable CBL140,
CBL154 or Model 831-INT Interface Unit
> 24 hours with power save options, 1 sec Leq logging
Power Consumption with PRM831
1.1 W (backlight off, running)
External Power
Test Conditions
Dynamic Range
Memory Retention
Data Memory
Non-volatile flash memory, backup performed every minute
Real-time Clock
≥ 10 minutes with batteries removed
Measurement Range [1]
Broadband Noise Levels
Self-generated Electrical Noise
0 dB Gain
20 dB Gain
18 - 140 dB
17 - 120 dB
18 - 140 dB
17 - 120 dB
23 - 140 dB
21 - 120 dB
28 - 140 dB
26 - 120 dB
29 - 140 dB
27 - 120 dB
35 - 140 dB
≥ 115 dB
24 to 140 dB
≥ 114 dB
25 to 140 dB
≥ 106 dB
32 to 140 dB
66 - 143 dB
34 - 120 dB
≥ 101 dB
19 to 120 dB
≥ 96 dB
23 to 120 dB
≥ 86 dB
32 to 120 dB
46 - 123 dB
66 - 143 dB
46 - 123 dB
77 - 143 dB
59 - 123 dB
140 dB
120 dB
143 dB
123 dB
0 dB Gain
20 dB Gain
Typical (dB)
Max (dB)
Typical (dB)
Max (dB)
Linearity Range [2]
Peak Range
Self-generated Total Noise
0 dB Gain
20 dB Gain
Typical (dB)
Max (dB)
Typical (dB)
Max (dB)
Note: Combination of the electronic noise and the thermal noise of the 377B02 microphone at 68 °F (20 °C) measured
in a sealed cavity and vibration isolated with an averaging time of 60 seconds.Electronic noise of the instrument with
an ADP090 (12 pF) in place of the microphone highest anticipated self-generated noise.
Max Level
[1] As defined in IEC 61672-1. Microphone and electrical self-noise included. [2] As defined in ANSI S1.4-1983.
Electrical Measurements.
Permanent Outdoor Preamplifiers and Microphones
Model 426A12
Model PRM2103
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Model 831 Options-at-a-glance
Fast Fourier Transform (831-FFT)
FFT lines
400, 800, 1600, 3200 or 6400
Frequency Span
100, 200, 500, 1000, 2000, 5000, 10000 or 20000 Hz
Hanning, Flattop or Rectangular
Frequency Weighting
A, C, Z
Bandwidth, Z Weighting
3 Hz to 20 kHz
Manual and Max Tracking with or without Harmonic cursors
Reverberation Time (831-RT)
Impulse Excitation and Interrupted Noise
1/1 (63 Hz to 8 kHz) and 1/3 (50 Hz to 10 kHz)
Sample Time
2.5, 5, 10 or 20 ms
T20, T30 and ISO 3382-2 quality indicators
Spectral Analysis with Octave Bands
Octave Analysis (Option OB3)
Frequency Range
1/1 Octave Filters
8 Hz to 16 kHz
1/3 Octave Filters
6.3 Hz to 20 kHz
Octave filter self generation noise at 1 kHz
1/1 Octave Filters
2.0 dB @ low range (0.2 dB in low range w/ 20 dB gain)
1/3 Octave Filters
-3.1 dB @ low range (-4.9 dB in low range w/ 20 dB gain)
Octave Analysis Parameters
Dosimetry (831-IH)
None, 1/1 octave, 1/3 octave, or 1/1 and 1/3 octaves
Frequency Weighting (independent
A, C or Z
of broadband)
Maximum Spectrum
Maximum in each band or Spectrum at broadband Lmax
Spectral Statistics
6 percentiles per band
Time History (see 831-LOG)
Measurement History (see 831-ELA)
Event History (see 831-ELA)
Octave Band Logging Capability
Directional Speaker
Normalized Spectrum
Two in parallel
Pre-configured settings
Exchange Rate
3, 4, 5, or 6 dB (independently selectable per dosimeter)
Selectable level
Criterion Duration and Time
Numeric input
Analog modem and Serial Communication
View Modes
SPL, Leq, Lmax or Lmin; absolute or relative
Predefined Filters
A, C, -A, -C
User Defined Filters
Four named for 1/1 octave and four for 1/3 octaves bands
Profiling with Time History Logging, Measurement History and Event History
Time History "TH" Logging (831-LOG)
Analog Modem Protocol
Requires fax quality line (no VOIP-like data compression allowed)
and an analog modem on host computer
Analog Modem Model
Analog Modem Support
Analog Modem Power Requirement Powered USB Hub or 831-INT Docking Station
Analog Modem Control
Model 831 USB port as host controller
Analog Modem Data Rate
2 to 3 kB/s (typical)
Serial Communication Prerequisite
USB to serial bridge (DVX008A)
Serial Communication Protocol
Measurement History "MH" Logging (831-ELA)
Serial Communication Control
Model 831 USB port as host controller
1 min to 99 hr
Wireless Modem (831-COMM) Over Internet
Logging Parameters
Same as Overall Measurements
Ln Statistics + Spectral Ln (if OB1 or OB3 enabled)
Wireless Modem Support
Sound Record Tagging
At start of each interval (required to enable SR)
Record Period
Logging Parameters
Selections from 20 ms to 24 h
2.5, 5 and 10 ms are available with option 831-FST
Any combination of available broadband and spectral
AnyData plus non sound metrics
Event History "EH" Logging (831-ELA)
Logging Period
Sound Record Tagging
20 ms to 5 s (independent of TH or MH)
Leq, Lmax, Lpeak, Date and Time, Duration, Exposure in dB and Pa2s, and available
spectral Leq and maximum. Event time history is also available with broadband and
spectral levels.
Required to enable SR at 8 or 16 ksps
Yes (LAE)
Logging Parameters
Sound Recording (831-SR)
Wireless Modem Protocol
GSM-GPRS Edge technology over internet Dynamic IP address support via
server initiated call Static IP address support when allowed by ISP provider
(does not require modem on server)
Z-Modem over TCP/IP
Wireless Modem Model
MDMUSB-E (Quad-band)
Wireless Modem Power Requirement Powered USB Hub or 831-INT Docking Station
Wireless Modem Control
Model 831 USB port as host controller
Wireless Modem Data Rate
2 to 3 kB/s (typical)
USB Communication
Standard Cables
Up to 16.4 ft (5 m), CBL138 is 6 ft (1.8 m)
Extended Cable
Devices are available that extend the connection up to 330 ft (100 m)
Data Format
Mono wave file (.wav), lossless
Weather (Meteorological Parameters)
Listening Options
On Model 831 using headset with Utility program, DNA or using standard
wave file player
Combined Meteorological Unit (SEN031)
Sample Rate
8, 16, 24 or 48 ksps
Storage Requirement
1 MB/min at 8 ksps to 6 MB/min at 48 ksps
Sound Recording Modes
Manual, Coupled to Marker, at measurement interval begin, upon
exceedance event
Up to 9 s
Max 9999 s
Sound Streaming
Streaming to host requires USB communication line (831 V1.6 or later)
Measurement Method
Digitized over serial port to USB
Sensor Model
SEN031 (requires CBL167, DVX008A and 831-WTHR)
Model 831-INT Docking station, or direct to Model 831 (external power
source required)
CBL170 break-out cable can be used with user provided anemometers
and analog sensors
Measured Parameters
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Wind speed and direction, temperature, relative humidity, rain and hail
Ordering Information
Model Number
Model Number
Model 831 Sound Level Meter for Environmental / Community Noise including
AnyData and Voice Annotation, without microphone or preamplifier
Model 831 Sound Level Meter with Class-1 free-field, pre-polarized precision condenser
microphone (50 mV/pa), preamplifier (PRM831), accessory kit (831-ACC)
Model 831 Sound Level Meter with Class-1 random-incidence pre-polarized condenser
microphone (50 mV/Pa), preamplifier (PRM831), accessory kit (831-ACC)
Upgrade Model 831 Sound Level Meter with logging of time histories with periods
from 20 ms to 24 hr
Upgrade for Model 831 Sound Level Meter. Exceedance based logging analysis
with event, interval and daily histories.
Upgrade Model 831 Sound Level Meter with Real-time 1/1 & 1/3 octave filter set
Upgrade Model 831 Sound Level Meter with sound recording. Adds sound snapshot
on demand, with Measurement History (831-ELA required) or on events.
Upgrade Model 831 Sound Level Meter to logging of time histories with periods
from 2.5 ms to 24 hr (requires 831-LOG & 831-OB3)
Upgrade Model 831 Sound Level Meter, Industrial Hygiene feature
Upgrade Model 831 Sound Level Meter, Advanced Communication Option controls
the EDGE modem (MDMUSB-E)
Upgrade Model 831 Sound Level Meter with Reverberation Time Analysis
Upgrade Model 831 Sound Level Meter with FFT Analysis
Upgrade Model 831 Sound Level Meter with Measurement History and Sound Recording
3 1/2 inch diameter windscreen for 1/2 inch microphone
Accessory kit for Model 831 Sound Level Meter, which includes case (831-CCS),
battery (4-AA), power supply w/ USB cable (PSA029) and windscreen (WS001)
Hard shell case for Model 831 Sound Level Meter
Headset with microphone boom, 0.09 inch (2.5 mm) sub-miniature plug
ICP® cable adaptor for Model 831 Sound Level Meter
Cable USB A to Mini-B 6 ft (1.8 m)
Cable 0.09 inch (2.5 mm) sub-miniature plug AC/DC out to BNC or RCA
Soft pouch for Model 831 and SoundTrack LxT®
90 to 264V to 12V switching power supply for 824 and 831 sound level meter and HVM100
AC Power supply for Model 831 and SoundTrack LxT® (100-240 VAC to 5 V USB
w/mini-B cable, CBL138)
12 VDC to USB Converter for SoundTrack LxT® and Model 831
DC power cable for Model 831 Sound Level Meter, 8 – 30 VDC includes
lead-acid battery clamps and 12 V car plug
Microphones and Preamplifiers
Model 831 Sound Level Meter preamplifier for 1/2 in free-field or random incidence
prepolarized microphones
1/2 inch free-field, prepolarized condenser microphone, typical sensitivity = 50 mV/Pa,
3.15 Hz to 20 kHz (±2 dB)
1/2 inch random incidence, prepolarized condenser microphone 50 mV/Pa,
3.15 Hz to 16 kHz (±2 dB)
1/4 inch pressure, prepolarized condenser microphone typical sensitivity = 1.6 mV/Pa,
4 Hz to 70 kHz (±2 dB)
1/4 inch microphone to 1/2 inch preamplifier adaptor
Permanent outdoor preamplifier with electrostatic actuator, humidity reading, TEDS and supporting
externally and pre-polarized microphone (microphone not included)
Permanent Outdoor Preamplifier for Model 831 with Remote Calibration Check, humidity reading
and heater, for pre-polarized microphone (MIC and cables not included)
SLM Utility-G4 software for SoundTrack LxT® and Model 831 sound level meter: download,
upgrade, translate, print text reports or export to spreadsheet. CD with Quick Start Guide
Basic software and dongle (USB) for evaluation and reporting of data downloaded from the
Larson Davis instruments, requires an instrument driver
Instrument driver for instrument control, set-up, live display, data translation, and data
download for Model 831 Sound Level Meter
DNA option for events tracking: PNL and PNLT event time history and EPNL event
DNA software Building Acoustics, allows calculation of transmission loss and sound
insulation calculations
DNA software for monitoring a remote location when using 820, 824, 870, or 831 Models.
Uses modem connection for communication and data download.
Class 1 acoustic calibrator with user selectable output of 94 or 114 dB at 1 kHz.
1/2 inch opening (no adaptor)
Class 1 microphone calibrator, output 114 dB at 251.2 Hz. 1 inch opening with 1/2 inch
(ADP019) adaptor. 3/8 inch (ADP020) and 1/4 inch (ADP021) adaptors available
Temporary Noise Monitoring System Components
Handheld Accessories
Sound Level Meter Options
Sound Level Meter
Case for Model 831 including (2) 21Ah bat, charger (PSA032), internal preamplifier cable
(CBL141), preamplifier cable (CBL142-006), power cable (CBL143), 3 ft mast
Case for Model 831 Sound Level Meter including (1) 21Ah battery, charger (PSA032),
internal preamplifier cable (CBL141), and power distribution cable (CBL151)
Environmental protection for 1/2 inch preamplifiers with windscreen,
bird spikes, desiccants and universal mounting
Instrumentation tripod w/ADP032 preamplifier to tripod interface
Support tripod, maximum height 8 ft (2.4 m) used in portable NMS systems
Adaptor connecting EPS2116 to TRP003 tripod
Waterproof cable connecting EPS029-831/EPS030-831 to external PC, 2m USB A-to-B
Permanent Noise Monitoring Systems
Permanent NMS on tilt-down pole using main power. Includes 831 (LOG, ELA), 831-INT,
TRP019, 426A12-FF, EPS031 (w/ 9Ah battery) and cables.
Portable NMS on tripod using solar power. Includes 831 (LOG, ELA), 831-INT, TRP020-20,
426A12-FF, EPS032 (w/ solar charger) and cables (required PSA012 and battery) .
NoiseTutor complete system including 831-FF with 831-OB3, 831-ELA and 831-LOG firmware
options and EPS2116. Also includes EPS041 that consists of weathertight case, 80 Wh battery,
embedded PC, HDMI display, wireless keypad, SWW-DNA-NT software, and wireless gateway.
NoiseTutor complete system including 831 with 831-OB3, 831-ELA and 831-LOG firmware options,
PRM2103-FF and EPS2116. Also includes EPS041 that consists of weathertight case, 80 Wh battery,
embedded PC, HDMI display, wireless keypad, SWW-DNA-NT software, and wireless gateway.
Noise Monitoring System Components
Model 831 docking station connecting weather sensors, batteries, charger and USB peripherals
Model 831 Docking Station with Ethernet (RJ45) connecting to power supply, weather sensors,
batteries, charger and USB peripherals
Surge suppressor for 110-240 VAC
Cable connecting Model 831 to 9-pin D connector (wind speed, direction, logic I/O,
3 slow ADC) and coaxial DC connector (to PSA027), including breakout cable and I/F block
Case on wheels (CCS035) with 100 Ah battery (BAT002) for permanent NMS, includes cable
(CBL149) to enclosure (EPS031 or EPS032)
Modem for Model 831 sound level meter with USB connection and dial-up
EDGE Modem for Model 831 Sound Level Meter with USB connection
USB Adaptor to DB9 interface (used with Serial modem or SEN031)
Combined weather sensor: wind speed and direction (no moving parts), temperature,
humidity, pressure, rainfall (requires CBL167 cable + DVX008A)
Noise Sources & Accessories
1 kHz, 94 and 114 dB, Calibrator
Omnidirectional Speaker
Calibration and certification of 831(SLM, preamplifier w/o microphone) and 831-RPT
Calibration and certification for microphone
Environmental certification Model 831 for [-40,+158] °F ([-40,+70] °C) range. Includes calibration
of 831 and PRM831, 831-RPT, environmental test of microphone. Microphone calibration not included.
Environmental Certification Model PRM2103 for [-40,+158] °F ([-40,+70] °C) range; (no
microphone certification); environmental test of microphone
Calibration and certification for 426A12 including environmental testing for temperature and
humidity stability. Replaces windscreen, o-ring, and desiccant cartridges.
Model 831 Sound Level Meter certification test report. Certificate for SLM,
preamplifier and microphone.
Lightweight Power Amplifier
Larson Davis | Toll-Free in USA 888.258.3222 | Phone: 716.926.8243 |
Larson Davis provides complete solutions for noise and
vibration measurement and analysis. From stand-alone,
simple-to-use instruments to complete systems including
sensors, data acquisition, and software, Larson Davis has
what you need.
As a division of PCB Piezotronics, Inc., Larson Davis guarantees
Total Customer Satisfaction through our outstanding limited
warranty; no-charge, 24 hours toll-free technical support;
global distribution; and worldwide customer service.
24350 Indoplex Circle, Farmington Hills, MI 48335 USA
Phone 716-926-8243 | Toll-Free in USA 888-258-3222
Fax 716-926-8215 | Email
© 2012-2014 PCB Group, Inc. In the interest of constant product improvement, specifications are subject to change without notice. PCB, and ICP are registered trademarks of PCB Group Inc., SoundTrack LXT, Spark
and Blaze are registered trademarks of PCB Piezotronics, Inc. HV Manager is a trademark of PCB Piezotronics, Inc. All other trademarks are properties of their respective owners.
Printed in U.S.A.
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