The difference between the two is significant. A few important limitations text to speech has:
In most cases, TTS provides non-natural, robotic emotions. AI doesn't know where to take emotions from, so it tries to generate them based on the text alone.
Very limited control over emotions. Some TTS can make the converted voice sound sad or excited using text annotation. But it is hard to manually encode intricacies of human acting using these annotations alone.
Words only. TTS are based on dictionaries. Unknown words and abbreviations pose a significant problem. Natural speech contains lots of non-verbal content as well. TTS struggles to render that.
Most TTS systems face challenges with low-resource languages due to higher data requirements.
The Respeecher voice cloning system works solely in the acoustic domain. We convey all the emotions and sounds of the source speaker while converting their timbre and other subtle variations into the target speaker.