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Curtain fabric, 25 cm from wall – PTB – Physikalisch-Technische Bundesanstalt | Acoustic Index

Search API Reverberation calculator

For professionals For manufacturers

TextileLow-frequency absorber

Data source

PTB reference data

Physikalisch-Technische Bundesanstalt

Source: J.Meyer, Kirchenakustik, Verlag E.Bochinsky

Curtain fabric, 25 cm from wall

PTB reference data

Original description

Curtain fabric, 25 cm from wall

Material properties

Wall distance:

25 cm

Measurement data

Sound absorption

ISO 354 – reverberation chamber

αw

0.62

Frequency values

αp nach ISO 11654

125 Hz

0.30

250 Hz

0.60

500 Hz

0.75

1000 Hz

0.60

2000 Hz

0.70

4000 Hz

0.75

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Method (354): Measured

The database for acoustic material data. Professional measurement results per ISO standards.

Products

Absorbers
Diffusors
All products

Company

About
Contact
For manufacturers

Tools

Read API
Reverberation calculator

Legal

Imprint
Privacy
Terms
Terms of use

© 2026 Acoustic Index. All rights reserved.