Testing of directional microphones under free-field conditions at low frequencies is problematic if an anechoic chamber is used beneath its cutoff frequency. In accordance to IEC 268-T4 guided waves in a correctly terminated duct can be used to produce a plane, travelling wave at low frequencies. An active absorber system is introduced which reduces the length of the tube and improves the reflection coefficient. First measurements in a test setup are presented.

Authors: Sander-Röttcher, Harald; Tams, Kersten
Affiliation: Sennheiser-electronic KG., Wedemark, Germany
AES Convention: 92 (March 1992) Paper Number: 3234
Publication Date: March 1, 1992
Subject: Measurement, Technique, and Instrumentation

Click to purchase paper as a non-member or you can login as an AES member to see more options.

No AES members have commented on this paper yet.

Subscribe to this discussion

To be notified of new comments on this paper you can subscribe to this RSS feed. Forum users should login to see additional options.

Start a discussion!

If you would like to start a discussion about this paper and are an AES member then you can login here:
Username:
Password:

If you are not yet an AES member and have something important to say about this paper then we urge you to join the AES today and make your voice heard. You can join online today by clicking here.