Sony TA-AV521 is an integrated stereo amplifier featuring surround sound capabilities and a range of audio adjustments. With its multiple input options, it can connect to various audio sources such as turntables, CD players, tape decks, and tuners. The amplifier allows for precise control over the audio experience, including speaker volume, delay time, tone, and bass reinforcement. Additionally, it offers surround sound modes to enhance the immersive experience, with adjustable rear and center speaker levels.