APEX/SPIN: a free test platform to measure speech intelligibility

Abstract

Objectives: Measuring speech intelligibility in quiet and noise is important in clinical practice and research. An easy-to-use free software platform for conducting speech tests is presented, called APEX/SPIN. Design: The APEX/SPIN platform allows the use of any speech material in combination with any noise. A graphical user interface provides control over a large range of parameters, such as number of loudspeakers, signal-to-noise ratio and parameters of the procedure. An easy-to-use graphical interface is provided for calibration and storage of calibration values. To validate the platform, perception of words in quiet and sentences in noise were measured both with APEX/SPIN and with an audiometer and CD player, which is a conventional setup in current clinical practice. Study sample: Five normal-hearing listeners participated in the experimental evaluation. Results: Speech perception results were similar for the APEX/SPIN platform and conventional procedures. Conclusions: APEX/SPIN is a freely available and open source platform that allows the administration of all kinds of custom speech perception tests and procedures.

Key Words:

• Speech perception
• behavioural measures
• test platform
• APEX

Acknowledgments

We are grateful to our colleagues at ExpORL, Department of Neurosciences, KU Leuven for providing valuable feedback on earlier versions of the software. We thank Job Noorman for helping with the programming.

Declaration of interest

The authors report no conflicts of interest. This work was supported by the KU Leuven Special Research Fund under grant OT/14/119.

Notes

¹The dynamic range of modern sound cards is mostly determined by its noise floor. While most sound cards support 24 bit output, many have a noise floor of around 90dB below the maximal output level, and therefore an effective dynamic range smaller than the number of bits would suggest.

²http://www.gnu.org/licenses/gpl-_2.0.html