Features 1、[HiFi BT Chip] This sound amplifier is equipped with HiFi Bluetooth chip and external antenna for long distance Bluetooth reception, tested to achieve over 50 meters. 2、[Powerful Amplification] With 20dB gain, this sound amplifier can drive various sound amplifiers, high impedance and low impedance earphones effortlessly. 3、[Sound Allocation] Featuring three sets of interfaces for simultaneous output, including two sets of phono connectors and a 3.5mm headphone jack, provides flexibility. 4、[Sound Mixing] The 3.5mm input interface can work simultaneously with Bluetooth sound, allowing for mixed sound output, enhancing the versatility and functionality of this amplifier. 5、[Flexible Power Supply] Power supply: DC5‑12V, working current: 5V 220mA, 12V 85mA, this sound preamplifier can be powered by a 12V power adapter, power bank, or a phone charger. Specification Item Type: Bluetooth Sound Amplifier Material: Aluminum Alloy Model: BT A30 Power Supply: DC 5-12V Current: 5V 220mA, 12V 85mA Sound Amplification Gain: 20db Input Interface: 3.5mm Dual Channel, Impedance 10k Output Interface: Phono Connector Dual Channel, Impedance 600 Ohms, 3.5mm Headphone jack, Impedance 16-600 ohms Operating Frequency: 20HZ-20KHZ Application: Turntable Speaker Package List 1 x Bluetooth Sound Amplifier 1 x Antenna 1 x Data Cable