Optimus+ GPS Sound Level Meter

We’re proud to announce the launch of the new GPS-enabled Optimus+ sound level meter, designed to make environmental noise monitoring easier and more effective than ever before.

The Optimus+ GPS builds on the incredible technology of Cirrus’ iconic Optimus range, by providing highly accurate location data for every measurement that’s taken. Optimus+ GPS automatically stores location data with each reading, which can be analysed in our licence-free data reporting software, NoiseTools.

There’s no need to purchase a whole new noise measurement instrument to benefit from the GPS functionality, you can simply purchase the module and add it to your existing Optimus+ Red or Green device. It’s also available as a full sound level meter kit.

With optimised battery life, the Optimus+ GPS is perfect for taking environmental noise measurements. The industry-leading time to first fix means that it is easier and faster than ever before to connect the module to a GPS signal.

Find your way through the noise with Optimus+ GPS from Cirrus Research.

MK:440 Environmental Noise Monitor

The MK:440 Noise Sensor is a robust and weatherproof outdoor noise monitor that converts measured noise levels into decibels, and provides a standard electrical output that is suitable for integration with various process systems.

Key features:

  • Lightweight and compact
  • Weatherproof design
  • Easy to install and set up
  • Designed specifically for integration into existing systems
  • No user-intervention required to record noise levels
  • Approved for use in non-incendive Class 1 Division 2 areas

Find out more information and speak to our noise experts on our website.

Environmental Noise Measurement Kit

The CK:685 outdoor noise kit is suitable for outdoor use with the Optimus+ Green sound level meters and provides you with a complete outdoor noise measurement solution for environmental and community noise monitoring.

Key features:

  • Fully weather protected outdoor noise measurement kit.
  • Purpose designed or use with the Optimus+ sound level meters.
  • Provides weather protection for an Optimus+ green sound level meter & microphone.
  • Hydrophobically coated windshield for optimum weather protection.
  • Battery power for 7 days operation with one standard battery pack (supplied).
  • Additional battery pack provides an additional 7 days power for up to 14 days operation.
  • External power connection for longer operation.
  • Secure lockable case with space for all standard instrument accessories.
  • Standard 10m microphone cable.
  • Optional microphone extension cables up to 100m.
  • Optional tripod available.

Find out more and speak to the experts on our website.

Invictus Environmental Noise Monitor

The Invictus is a range of next generation environmental noise measurement instruments from Cirrus Research, that is available as either a portable noise monitor, ideal for short and medium-term measurements, or an installed system designed for long-term measurements.

Key features:

  • Colour touch screen interface simplifies set up and deployment.
  • Simultaneous measurements of all parameters.
  • Noise event detection with in-measurement audio recording, SMS, Email & Twitter alerts.
  • Live audio playback via the Noise-Hub2 software.
  • 120dB measurements range in a single span.
  • Full weather protection with dual-skinned windshield.
  • 32GB data storage as standard.
  • External calibration with microphone performance verification.
  • GPS location information stored with each measurement.
  • Option of weather measurements integrated with noise data.
  • External power input for long term operation

Find out more and speak to the experts on our website.

Galactus Environmental Noise Monitor

The CR:465 Galactus instruments are a range of high performance noise monitors that have been designed to integrate with external data loggers and environmental measurement systems and to provide a comprehensive set of acoustic data.

Comprising a processor unit and a fully weather protected microphone system, the Galactus instruments meet the Class 1 requirements of IEC 61672 and IEC 61260 and can provide a comprehensive set of user configurable acoustic data parameters via an industry standard RS232 protocol.

The Galactus instruments can provide the acoustic information required to calculate the parameters defined in ISO 20906:2009 making the units ideal for the monitoring and measurement of unattended aircraft noise.

The CR:465 Galactus instruments are controlled by a set of commands that are sent to the unit via a standard RS232 communications protocol.

This allows for full external control of all aspects of the instrument, including calibration and verification using the electrostatic actuator system. This allows the units to be integrated quickly and easily alongside other sensors and data sources.

Measurement data is returned as packets of information via the RS232 port with the packets sent at either 1 second or 0,5 second intervals. These packets can contain any of the acoustic measurement values which can be configured to suit the application in which the instrument is being used.

To allow for the calculation of Ln values in accordance with ISO 20906:2009 “Acoustics – Unattended monitoring of aircraft sound in the vicinity of airports”, the data packets can contain 1/8th second LAS data points allowing exceedence levels (% LN values) to be calculated.


Key Specification Features

  • Class 1 performance to IEC 61672 & IEC 61260
  • Total Measurement Range of 20dB to 140dB RMS (Single Range)
  • Simultaneous measurement of:
  • A,C & Z frequency weightings
  • F,S & I time weightings
  • 1:1 octave bands from 31,5Hz to 16kHz
  • 1:3 octave bands from 6,3Hz to 20kHz
  • Live data output of:
  • Lxy (Sound Pressure Level)
  • LxyMax (Maximum Sound Pressure Level)
  • LxEQ (Equivalent Continuous Sound Pressure Level)
  • LxEQ16MAX – Maximum Leq,62.5ms (1s)
  • LxPEAK – Peak Sound Pressure
  • OCTz – 1:1-Octave band Leq
  • 3OCTz – 1:3-Octave band Leq
  • Where x is A, C or Z and y is F, S, or I
  • Simultaneous measurement of A,C & Z and F, S & I

The rear panel 15 way D-type connector also provides the option of a 4-20mA current loop output which can be used with standard interface modules.

MK:427 NoiseSensor

The MK:427 Noise Sensor is an outdoor noise measurement instrument that has been specifically designed for integration with other data logging and monitoring systems.

Key features:

  • Robust, fully weather protected Class 1 outdoor microphone.
  • Straight forward integration with industry standard 4-20mA current loop systems.
  • Eliminated the need for third party software.
  • 30 to 100dB(A) standard range ideal for most applications.
  • Proven long term reliability in harsh outdoor environments.
  • Verification through regular scheduling for remote calibration using integrated electrostatic actuation system.
  • Outdoor windshield and bird spikes to protect the microphone.
  • Entire length of the MK:427 NoiseSensor is 1m.
  • Simple mounting and installation for quick deployment.

Find out more and speak to the experts on our website.

Optimus+ Green Sound Level Meters

The Optimus+ Green is the all-in-one solution that gives you all the noise data you could possibly need for both environmental and occupational noise.

Key features:

  • Backed by our 15-year warranty.
  • High performance to Class 1 or Class 2 standards.
  • Quick, simple and easy-to-operate.
  • Simultaneous measurement and data logging of all available parameters.
  • Compatible with select environmental noise monitoring kits for a total environmental noise monitoring solution.
  • Bluetooth connectivity that allows the meter to be controlled from compatible smartphone.

Find out more and speak to our noise experts on our website.


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