Fact · Dictation
8.67percent word error rate
In the same preliminary Wall Street Journal task, narrowband (8 kHz) speech gave a word error rate of 8.67%.
Checked against its source on October 16, 2026
In the source's own words
“wideband speech, with a word error rate (WER) of 8.12%, can always outperform narrowband speech, with a WER of 8.67%”
DNN-based speech bandwidth expansion and its application to adding high-frequency missing features for automatic speech recognition of narrowband speech, Kehuang Li et al., Interspeech 2015, International Speech Communication Association (ISCA), 2015, Introduction, paragraph 2.
Open the original- What it measures
- The same comparison as the 8.12% result, with the narrowband figure. Narrowband is the audio bandwidth used by many telephone and Bluetooth voice links.
- What it does not show
- The gap is small on clean read speech. Expect a larger gap in noise, which the authors did not test in this comparison.