Newman digital recorder RV9 user manual introduces the product's features, including recording types, one-key recording function, timer recording, real-time time, voice control recording, telephone call content recording function, lyrics synchronization display, built-in microphone, high-fidelity recording, multiple audio formats, convenient language learning function, real digital repeater, fragment A-B repeat, original sound comparison follow-up, 16-segment variable speed playback, natural, rock, jazz, bass and other seven sound equalizers