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Pass-By Noise Testing

VBOX systems make it quick and easy to test a vehicle's noise emissions levels to ISO and ECE standards.

  • Test to ISO 362, ECE R41, R51, R117 & R138, US EPA
  • Automobile, motorcycle & electric vehicle testing
  • Simple installation and testing with just one operative
  • Free Pass-By Noise testing software

Pass-By Noise Testing with VBOX 

VBOX Pass-By Noise testing equipment allows you to log channels such as engine RPM, vehicle velocity and maximum vehicle exterior noise to the accuracy requirements of ECE/ EPA standards and regulations. Certification of vehicle noise emissions for tyres, passenger vehicles, motorcycles and light trucks is achieved with dedicated Pass-By-Noise plugins for EPA, ECE R41, ECE R51, ECE R117 and ECE R138.

Single Person Testing

The VBOX Pass-By Noise system can be installed in the test vehicle, meaning only one driver is required to complete each test.

Log Simultaneous Channels

Simultaneously log speed, acceleration, engine RPM and throttle position - all the required parameters for Pass-By Noise testing.

Data Analysis Software

VBOX Test Suite is free to all VBOX users, available in ten different languages and pre-installed with a dedicated Pass-By Noise plugin.

Highly Accurate Measurements

The VBOX 3i data logger provides high accuracy distance measurement, which negates the need for multiple light-barrier trigger systems.


Allows for compliance testing to ECE R41 (motorcycle), R51 (automobile), R138 (quiet vehicles, e.g. electric) and R117 (tyres) standards, as well as to EPA regulations.

Noise & Weather Data

Sound pressure levels can be logged in conjunction with specialist microphones, as well as live weather data from a Davis Vantage Pro 2.

Free Data Analysis Software

Our intuitive VBOX Test Suite analysis software comes with dedicated Pass-By Noise plugins that are compliant with EPA, ECE R41, ECE R51, ECE R117 and ECE R138 standards.

VBOX Test Suite allows you to enter session-specific information that defines test conditions and vehicle details, like the requirement of kerb mass, power, idle rpm and rated engine rpm when testing to R51/R41.

This information is automatically saved to the log file and so only needs to be entered once; it can also be exported for use in another file, saving setup time.

A comprehensive report can be generated at the end of the test, providing all session information and results for post-test analysis.

Please hover over the software screenshot for more information.

Live Display

Choose the channels you want to see displayed live from your vehicle or on site, in real-time.

Graph Display

A graph plotting distance against decibel levels allows you to easily compare results side by side in order to recognise trends or variances.

Test Results

Results will populate as soon as test runs are completed. The data displayed is specific to the test standard. Additional channels can be added if required. Results which do not meet the standards selected will be highlighted in pale red, with the parameter by which the run failed made clearly visible.

The software will create different tabs at the top of test results area to differentiate between test-specific runs, e.g. wide-open throttle, steady speed and ASEP runs for the R51 and R41 tests.

Report Generation

A comprehensive report can be generated at the end of the test, providing all session information and results for post-test analysis.

Image: R117 report example


You are able to configure the software by selecting the start conditions and channel parameters.

Image: R138 setting screen example

Testing Equipment

A typical Pass-by Noise (PBN) test setup consists of a VBOX 3i 100 Hz data logger, a Laser Light Barrier Kit, a tablet or PC, a Mini Input Module, sound level meters and telemetry radios. The difference between the layouts for each regulation is that the PC or tablet can be easily installed inside the vehicle for R51, R117 and R138 testing instead of the roadside for R41 and EPA testing.

Measuring sound pressure levels

Microphones placed within the test area output to a VBOX Mini Input Module, which continuously transmits the converted sound readings via 2.4 GHz telemetry radios to the VBOX 3i GPS data logger.

Centimetre-level accuracy with VBOX 3i RTK

Instead of using a laser light barrier to trigger the start of the test, a VBOX 3i RTK can be used to set the start and finish lines when used with an RTK Base Station or NTRIP solution. This means that the test vehicle doesn’t have to come to a stop between test runs and can save valuable time.

VBOX 3i Dual Antenna for R138

The R138 regulation requires conducting the tests in the forward and reverse direction. When using a VBOX 3i Dual Antenna, the VBOX Test Suite R138 Plug-in can automatically detect the direction of travel of the vehicle and categorise the results for each prescribed test direction and speed.

Rugged motorcycle equipment case

This case can be installed on motorcycles for R41 or EPA Pass-by Noise Testing. It can hold the VBOX 3i, CAN splitters, 2.4 GHz telemetry radio, Base Station radio and Li-ion battery. It has mounting brackets for up to 1 inch straps as well as a GPS ground plane.

Rugged roadside case

This case is placed near the Sound Level Meters by the roadside. It can hold the Mini Input Module, the 2.4 GHz telemetry radio and a Li-ion battery.

Tablet or PC for live data display

VBOX Test Suite Software can be used for viewing and analysing live data, as well as for post-processing.