Technical Column
Indoor Coast-by
2025年5月23日
Standard for Indoor Noise Testing of Tires Using a Drum Test Machine
In 2023, ISO 20908:2023 was introduced as a new method for indoor testing of tire noise emissions.
“Tyre sound emission test. Methods of drum”
Compared to the existing outdoor measurement method ISO 13325, this ISO standard appears to be the first edition specifically for indoor measurements.
Similar to ISO 362-1, 362-2, and 362-3, which measure vehicle pass-by noise, this new standard was established to enable testing that was previously limited to outdoor environments to now be conducted indoors.
There is a growing trend toward performing vehicle noise measurements indoors through “indoor pass-by” methods, as opposed to traditional outdoor test tracks.
Outdoor tests have been subject to weather conditions, such as rain and strong winds, which restricted testing to specific times. However, with the introduction of ISO 20908, efficient and flexible indoor testing has become possible.
That said, constructing an indoor testing facility requires a wide range of equipment, including a drum system, a semi-anechoic chamber, and precise temperature control.
Additionally, it is necessary to properly address the sound components of rolling noise based on ISO 10844.
As a manufacturer of anechoic chambers, we are capable of proposing facility designs that meet the required specifications, including temperature-controlled environments and microphone array layouts based on the inverse square law.
Temperature control is managed in a manner similar to a thermal chamber, with insulation applied to the walls, ceiling, floor, and doors of the anechoic room, combined with an advanced HVAC system.
While the temperature ranges required by ISO 362-3 and ISO 20908 may differ, the measurement methods based on the inverse square law are similar to those defined in ISO 362-3.
Furthermore, considering the relationships with other standards, the newly established “Indoor Coast-by” evaluation method now enables quantitative assessment of tire coast-by noise at any time.
Drawing on our extensive experience and knowledge, we are committed to designing rooms and measurement systems that comply with these latest standards.
Please feel free to contact us for more information.
Latest Posts in Technical Column
-
2025.09.15
Automated Acoustic Testing for Wireless Communication Modules — AEB × HBK System for Bluetooth Mics, Headsets, and Voice Devices — -
2025.09.10
Efficient Acoustic Testing for Compact Electric Devices — EAAC × HBK Analysis Enables Fast, Reliable Mass Production Checks — -
2025.09.05
Mapping the Directionality of Acoustic Devices — Directivity Measurement with HBK Microphones, Turntable, and AEB — -
2025.08.31
Visualizing Noise with Acoustic Cameras — How Measurement Environments Affect Beamforming Accuracy — -
2025.08.26
Why Measurement Rooms and Measurement Instruments Must Be Designed Together — Managing Environmental Noise and Instrument Precision as a Unified System — -
2025.08.21
Automated Sound Pressure Scanning for ISO 26101 Validation — Free-Field Compliance Using HBK + Traversing System in Sonora Anechoic Chambers — -
2025.08.16
Non-Invasive Acoustic Testing for Sealed Devices — Inspecting Internal Sounds from Outside with AEB × HBK Sensors — -
2025.08.11
Acoustic BOX Integration with HBK PULSE — Quiet Test Environments for Fully Automated Acoustic Inspection — -
2025.08.06
Precision Sound Power Measurements with ISO 3744 × HBK PULSE — Reliable Inverse Square Validation with SPAC and Certified Instruments — -
2025.08.01
Powertrain NVH Testing for EV and Mobility Applications — Multiaxial Measurement of Torque, Vibration, and Noise with VSAC × HBK Sensors —
Contact Us
- Contact us by email
-
- Contact us by phone
-
Moritani Shokai
(Machinery Department No. 2, Tokyo Head Office)
Introduction of the Manufacturer
-
Hottinger Bruel & Kjaer
HHBK is a merger of two companies: Brüel & Kjær of Denmark and HBM of Germany.
Brüel & Kjær is one of the world’s leading manufacturers of acoustic and vibration measurement instruments, known as a total measurement chain supplier.Learn more about HBK
-
Sonora Technology Co., Ltd.
Sonora Technology is a leading Japanese manufacturer of industrial anechoic chambers and anechoic boxes.
From design and manufacturing to installation and acoustic performance assurance, Sonora provides fully integrated solutions to build complete acoustic measurement environments from the ground up.Learn more about Sonora
Contact / Request Brochure
For inquiries or consultations regarding the total solutions provided by HBK × Sonora, please feel free to contact us using the Contact button.
If you would like a brochure sent by mail, please use the Request Brochure button.