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Acoustic absorber materials

Unique, high performance materials

NPL has expertise in the design and development of bespoke acoustic absorber materials for immersion applications. These combine high levels of echo reduction and insertion (transmission loss) and can typically be used to line the walls of water-filled test tanks to reduce the impact of reflections on measurement and to support precision instrumentation such as radiation force balance targets.

Several NPL developed acoustic absorbers are available to order from Precision Acoustics who is the sole supplier of this range and these are summarised in the table below. Web-links provide details of the material characteristics, including acoustic properties determined at NPL. The acoustic absorbers may be broadly divided in high frequency (above 200 kHz) and low frequencies down to 10 kHz.



Further information


High quality material for medical ultrasound applications such as radiation force balance targets.

High frequency anechoic material.

Aptflex F28

Provides a cost effective method of absorbing ultrasonic reflections ensuring acoustic isolation.

High frequency anechoic material.

Aptflex F28P

Pyramidal structured absorber for radiation force balance targets designed for acoustic powers greater than 20W, but less than 100 W.

High frequency anechoic material.

Aptflex F36

Two-part mix kit version of the Aptflex F28. It has the same acoustic properties of the tile Aptflex F28 but can be cast into specific shapes.

High frequency anechoic material.

Aptflex F48

Designed to meet the requirements to reduce reflections in sub MHz frequency acoustic test tanks.

Low frequency anechoic material.

Apltile SF5048

Single-ply absorber made from Aptflex F48 with a structured front surface designed to scatter incident sound.

Low frequency anechoic material.

Alberich tile

Structured material based on Aptflex F48, designed to boost insertion loss at low acoustic frequencies.

Low frequency anechoic material

All the products have been developed and tested by NPL and Precision Acoustics and have the NPL Technology Applied status. NPL Technology Applied is a co-branding scheme for instrumentation and software technology developed by NPL and incorporated into a range of commercial products.

acoustic absorbers

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