Dynamic Range Compression for Voice AI

Dynamic range compression (DRC) in voice AI is a preprocessing technique aimed at reducing amplitude differences between loud and quiet audio segments, which can occasionally enhance transcription accuracy in specific scenarios like multi-speaker environments with significant loudness variation. However, the article argues that most automated speech recognition (ASR) systems do not require external DRC, as modern models are designed to handle acoustic variability internally. The practice of applying DRC can degrade audio quality if not used cautiously, as aggressive compression may strip essential prosodic cues and introduce unnecessary signal degradation, especially if a provider already applies internal normalization. The article recommends using DRC only after verifying a level-variation issue that models cannot absorb and emphasizes the importance of conservative settings and thorough A/B testing with specific ASR providers to ensure such preprocessing genuinely benefits the accuracy of transcription.