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Phone audio, accents and noise
Why a voice agent that works in a demo can fail on a real phone line, and how to test accents, narrow audio and background noise.
Short answer. A demo usually runs on clean, wide audio. A real call arrives narrow and compressed, sometimes noisy, from a caller whose accent the speech recognition may handle badly. Test on the line your callers use, not the one your laptop has.
Test the line, not just the words. The same sentence can be heard correctly in a studio and wrongly on a phone.
Start with this guide
UK accents over phone audioTesting accents and background noise
Why recognition errors rise on narrow phone lines and regional accents, what studies found, and how to test.
Build an accent mix from your real callers, add noise at set levels, degrade to phone audio and report by group.
The words you need
- Word error rate, the share of words a transcript gets wrong.
- Voice-to-voice latency, the gap the caller actually hears.
Also see
- UK accents benchmark, the method and how to rerun a result.
- Voice agent testing, the guide