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Optimus Yellow Data Logging Sound Level Meter

Data Logging Sound Level Meter
Data Logging Sound Level Meter
Data Logging Sound Level Meter Clear Colour Display

Price List

USD $1511.00
Data Logging Class 2 Sound Level Meter
In stock

USD $2042.00
Kit with Logging Class 2 Sound Level Meter, Calibrator, Software and Case
In stock
USD $2521.00
Data Logging Class 1 Sound Level Meter
In stock

USD $3212.00
Kit with Logging Class 1 Sound Level Meter, Calibrator, Software and Case
In stock
USD $467.00
Class 2 Sound Level Calibrator
In stock

USD $656.00
Class 1 Sound Level Calibrator
In stock
USD $81.00
DC Output Cable - 18 pin to phono, 1 m
Lead time 1 week

USD $169.00
RS232 Cable - 18 pin to 9 pin D female
Lead time 1 week

USD $138.00
Microphone extension cable 2 m
Lead time 1 week

USD $162.00
Microphone extension cable 5 m
Lead time 1 week

USD $202.00
Microphone extension cable 10 m
Lead time 1 week

USD $250.00
Microphone extension cable 20 m
Lead time 1 week

The delivery price is calculated during checkout based on your location and the goods ordered. Our basic delivery prices are:

Delivery within India: $82.00

Delivery Service: Five working days*

* For products that are in stock and the order received by midday.

Some products go through a final configuration and calibration before being shipped. If the calibration labs are busy this can add up to two days on to the delivery schedule but guarantees a fresh calibration.

USD $1511.00
Data Logging Class 2 Sound Level Meter
In stock

USD $2042.00
Kit with Logging Class 2 Sound Level Meter, Calibrator, Software and Case
In stock


  • Simple to use
  • Simultaneous measurement of all parameters
  • 120 dB measurement range
  • Data logging with VoiceTag (audio notes)
  • A, C and Z weightings
  • Fast, Slow and Impulse response
  • Bluetooth connection to mobile app
  • 15 Year Warranty


  • Basic noise surveys
  • Noise ordinance enforcement
  • Fire alarm testing
  • Machinery maintenance and trouble-shooting

Optimus Yellow

The CR15xB Optimus Yellow is a calibrated, professional grade sound level meter for noise measurements that must meet the relevant international standards. Despite being a powerful meter it is extremely easy to use, ensuring you get the correct measurements from the start.

The Optimus range of sound level meters uses the latest display technology and digital signal processing (DSP) techniques to provide you with a very powerful yet easy to use meter. The ease of use comes from the fact that all parameters are automatically measured at the same time, so no need to think about what you need in the split second before starting the measurement.

Making Noise Measurements

Making measurements usually consists of checking the calibration (adjustments are automatic), recording a voice tag if required, and then taking the readings.

As this meter is a data logger all the measurement parameters are stored along with time, date and other relevant information.

Future Upgrade

If you decide at a later date that you need an Integrating sound level meter or even octave band filters then we offer a simple upgrade path.

These features can be added at a later date. Some can even be fitted without returning the meter to the factory by remote update.

We can even change the meter from Class 2 to Class 1, although of course it must be returned for this upgrade.

Visit the Options tab for more details.


The Optimus Yellow is ideal for applications that need a wide measurement range (20 to 140 dB) but do not need an integrated average (Leq or Lavg). This data logging version offers more indepth reporting via the NoiseTools software, which is included with the meter.

  • Alarm installation and testing
  • Machinery servicing and maintenance
  • Office noise checks
  • Noise ordinance enforcement
  • System integration

General Noise Survey

As this meter meets the strict IEC 61672 standard to Class 2 or Class 1, depending on the model you choose, it can be used to make accurate and repeatable measurements.

If the regulations you are measuring to do not require an integrating meter then this one should be ideal.

Fire Alarm Testing

The standards for fire alarm testing usually demand the measurement of the "A" weighted "Fast" sound level. The CR152A sound level meter provides this measurement.

System Integration

The Optimus Yellow has both AC and DC outputs, making it ideal for connection to a data logging system via a suitable A/D converter. Please note that some outputs require an extra cable. Please contact us for more information.

Noise Measurement

One of this meter's most useful features is its ability to measure all the noise parameters at the same time. When the time comes to make a measurement, you have no doubts about whether you have the correct settings.

Measures all parameters at the same time:

  • Fast, Slow, and Impulse time weightings
  • A, C and Z frequency weightings
  • Maximum (Lmax) and Minimum (Lmin) for all of the above

For download to the software the meter stores:

  • Max sound level (Lmax)
  • A, C, Z frequency weightings
  • Fast, Slow, Impulse response
  • Time History (see below)
  • Date, Time and run time
sound level parameters

Most noise measurement regulations will clearly state the parameters that should be measured. For most, this will include the "A" weighted Sound Level, with a time response of either Fast or Slow. To keep things clear, the meter shows only the most commonly used parameters on the screen.

In this example, the display shows the current Fast Sound Level (LAF) as a large number. Below that are the maximum (LAFmax) and the minimum (LAFmin) and the measurement time.

The bar on the left shows the current sound level. It can be set to change color when preset levels have been exceeded.

Data Logging - Parameters Stored

The display shows the commonly used parameters but the meter stores the maximum sound levels for all time and frequency weightings, along with a time history for the more common ones.

Summary Store

The overall parameters for the noise measurement are stored for all frequency and time weightings.

Time History Store

The meter can be set to store time history measurements at one of a number of rates between 10ms and 2 seconds. Four maximum sound level (Lmax) values are stored for each sample: LAFmax, LASmax, LCFmax, LCSmax.

Voice Tag

Before starting a measurement, the meter will ask if you want to record a "Voice Tag". The meter will record any speech or the noise in question (to help you identify it later) for up to 30 seconds. This audio is transferred to the software automatically along with the measurement.

You can skip this stage if you don't need a voice tag, or the option can be disabled altogether.

noise time history
Time History Shown in the Software

Using the Optimus Yellow

The Optimus range of sound level meters have a single measurement span and measure all the noise parameters at the same time. This means that you do not have to think about a range setting (there isn't one) or which measurements you need first. Just switch on and make the measurement.

Power Up

The meter takes just four AA batteries (included), which should last at least 12 hours - that's a lot of noise measurements.

switch on

Start the Measurement

start the noise measurement

Press the Start button to begin the noise measurement

Once running, the meter will show the current sound level along with the maximum and minimum levels. Other parameters can be viewed (such as "C" weighted and "Z" weighted levels) by using the up and down arrow keys.

The meter is already storing measurements. It stores everything, no need to choose anything here.

Stop the Measurement


At the end the measurement process press the Stop button. The display will show the most common measurement parameters: Maximum Sound Level and Minimum Sound Level with the usual "A" weighting applied. Using the up and down keys, you can also view the "C" and "Z" weighted values.

The measurement is automatically stored at this point, ready for download to the NoiseTools software.

Data Logging Meters

The data logging Optimus Yellow (CR151B and CR152B) include the NoiseTools software - there is no extra charge for this. You can download the software to evaluate it before making a purchase.

NoiseTools Software

The NoiseTools software runs on a Windows PC. It is compatible with all recent versions of Windows, from Windows 7 onwards.

  • Downloads measurements from Optimus Yellow
  • Produce noise reports
  • Print or export reports for sharing
  • Listen to Voice Tags
  • Hearing protection selection reports
  • Link measurements to projects, people and places
  • Free, lifetime updates
  • Licence free with no installation restrictions

More information about NoiseTools

In The Box

You can buy the Optimus Yellow as a sound level meter on its own or as part of a noise measurement kit. For this grade of meter, most customers have the measurement kit, as it includes a sound level calibrator, which is a requirement for many noise regulations.

Sound Level Meter

Order codes CR151B and CR152B include the following items:

  • Optimus Yellow Sound Level Meter
  • User Manual
  • Calibration Certificate
  • USB Cable
  • Windshield
  • NoiseTools Software

Noise Measurement Kit

Order codes CK151B and CK152B include the following:

  • Optimus Yellow Sound Level Meter
  • Sound Level Calibrator
  • Windshield
  • Carrying Case
  • User Manuals
  • Calibration Certificates (for meter and calibrator)
  • USB Cable
  • NoiseTools Software
StandardsIEC 61672-1:2013 Class 1 or Class 2
IEC 61672-1:2002 Class 1 or Class 2 Group X
IEC 60651:2001 Type 1 I or Type 2 I
ANSI S1.4 -1983 (R2006), ANSI S1.43 - 1997 (R2007)
ANSI S1.25:1991
MicrophoneClass 1 MK:224 pre-polarized, Class 2 MK:216 pre-polarized
Measurement Range20dB to 140dB RMS Single Range
Noise Floor<18dB(A) Class 1, <21dB(A) Class 2
Frequency WeightingsRMS & Peak : A, C, & Z Measured Simultaneously
Time WeightingsFast, Slow & Impulse Measured Simultaneously
DisplayHigh resolution display. Ambient light sensor & illuminated keypad
Memory8GB, 32GB factory fit option
Time History Data Rates10ms, 62.5ms, 125ms, 250ms, 1/2 sec, 1 sec, 2 sec (User selectable)
VoiceTag Audio RecordingUp to 30 seconds of audio notes with each measurement
DimensionsSize: 283mm x 65mm x 30mm
Power4 x AA Alkaline
Typically 12 hours with Alkaline AA
Typically 20 hours with Lithium AA Non-Rechargeable
External Power: 5v-15v via MultiIO socket via ZL:171 cable (2.1mm socket)
ConnectionsUSB Type B to PC
AC & DC Output via ZL:174 (2 x Phono, 1m)
Multi-pin IO for external power via ZL:171 cable (2.1mm socket)
External Power: 5v-15v via MultiIO socket via ZL:171 cable (2.1mm socket)
Tripod Mount1/4" Whitworth socket
CaseMaterial: High Impact ABS-PC with soft touch back & keypad
EnvironmentalTemperature: Operating -10°C to +50°C, Storage -20°C to +60°C
Humidity: Up to 95% RH Non Condensing
Electromagnetic performanceIEC 61672-1:2002 & IEC 61672-2:2003
Except where modified by EN 61000-6-1:2007 & EN 61000-6-1:2007
Language optionsEnglish, French, German, Spanish. Other language options may be available
Software SupportNoiseTools Download, Configuration & Analysis software supplied as standard. Compatible with Microsoft Windows XP, Vista, 7, 8 & 10 (32bit & 64bit)
Displayed FunctionsLXY, LXYMax, LXYMin, Run Time
Stored FunctionsLXYMax & Time History of LXYMax, Start Time
where x=A ,C ,Z; y= F, S, I