Effects of active noise cancelling headphones on speech recognition

To evaluate the influence of active noise cancelling headphones on speech recognition, word recognition tests were performed for 16 young adults with normal hearing using 3 typical active noise cancelling (ANC) headphones on the market. The listening materials are 10 Chinese words and 10 English words, the background noise is white noise, and word recognition rates for the signals are compared with 6 different signal to noise ratios (SNR), i.e. –15 dB, –10 dB and –5 dB for the Chinese words test, and –5 dB, 0 dB and 5 dB for the English words test. The results reveal that the word recognition rate increases if the active noise control function is on under all conditions due to the increase of the SNR for the sound on the subjects’ ears. If the active noise control function is off while wearing these headphones, the word recognition rate decreases due to the reduced sound energy caused by the passive noise reduction of the headphones.