SS03: REALISTIC ASSESSMENT OF SPEECH AMPLIFICATION

NEW STANDARD TEST METHOD FOR THE CHARACTERIZATION OF HEARING DEVICES

Todd Fortune

GN Resound, Bloomington, USA.

A new method for testing speech amplification that incorporates the ISTS and the standard set of audiograms has been completed. Testing is performed in a standard test chamber using either a 2cc coupler or a real ear simulator. Devices are tested as they would normally be used, i.e without the need for special testing settings or programs. Speech gain is determined by comparing time-aligned averages of 30th, 65th and 99th percentiles for the input and output signals. This method provides a realistic assessment of speech amplification and is particularly useful in revealing the true effects of time constants, e.g. how fast compression differs from slow compression in terms of the amplification of speech. Initially this method will be used by manufactures to quantify hearing aid performance, but a clinical version is currently under discussion with several testing equipment manufacturers.  The final talk of this session will describe the test method and will focus on its application i.e. how different hearing aid types and configurations differentiate themselves when tested using the ISTS, a specific reference audiogram and the new test method.