Editing Mean Opinion Score (section)

=== Speech Synthesis and AI ===

In modern artificial intelligence applications, MOS has become critical for evaluating text-to-speech (TTS) systems. As synthetic speech quality has improved dramatically with neural approaches like WaveNet, Tacotron, and VITS, MOS remains the primary method for assessing how natural and human-like synthesized speech sounds to listeners.

However, recent research has highlighted limitations of MOS for evaluating state-of-the-art speech synthesis systems. Studies have shown that as synthetic speech approaches human quality, MOS becomes less sensitive to remaining differences, leading researchers to explore complementary evaluation methods.<ref>https://www.sciencedirect.com/science/article/abs/pii/S0885230823000967</ref>