<p>The board uses the PT2399 built-in chip to return to sound processing, and the setting is the four amp field effect opTL074 for audio signal amplification and sound processing.</p> <p>Also added a new 5V output, can be connected to the USB Bluetooth decoder board, more convenient to use.</p> <p>In addition, the karaoke card also uses a two-way microphone input (compatible with electret microphone)</p> <p>Working voltage: Double AC12 ~ 15V</p> <p>Colour: green</p> <p>Material: plastic</p> <p>Size: 157x88mm</p> <p>Package Contents:</p> <p>1 * Microphone Amplifier Tone Board</p> <p>NOTE:</p> <p>This is the front tuning card of the amplifier. Need to be equipped with a post amplifier to use.</p> <p>If you contact for the first time, you might not understand,</p> <p>This card is set up with a station amplifier and has no audio output. You need to match a post amplifier. Just import the signal from the preamp.</p> <p>Pre-tuning signal-input post-amplifier-post-amplifier pushes signal processing to the speaker</p> <p>Only the above package content, other products are not included.</p> <p>Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +\/- 1-3cm.</p>