Here's a concise introduction to the TDA7319: The STMicroelectronics TDA7319 is a digital-controlled stereo audio processor chip that offers advanced features for professional and consumer audio applications. This PDIP-20 packaged chip boasts four stereo inputs, selectable gain (0dB/6dB), built-in input multiplexing, and four independent speaker outputs with soft step volume control. The TDA7319 also features a standby function for efficient power management. Its versatility makes it suitable for various applications, including car audio systems, home stereo systems, portable audio devices, professional audio equipment, personal computers, televisions, gaming consoles, smartphones, tablets, and DJ equipment. Features The TDA7319 features include: 4 stereo inputs Selectable gain (0dB/6dB) Built-in input multiplexer 4 independent speaker outputs Soft step volume control Standby function