?<strong>Features:</strong> <br>HiFi tube amplifier£¬ mellow and plump sound. <br>Eight 470UF capacitor filter£¬ pure power supply system£¬ no hum. <br>Boost AC 12V to 28V: prolong the tubes' life-span and improve S/N. <br>Comes with 3 tubes: 2 for normal working£¬ 1 for standby. <br>With volume controller£¬ 2 audio input and output interface. <br>With LEDs on the bottom of the tubes£¬ send out soft orange light when it is working. <br>Great for smartphone£¬ computer£¬ CD£¬ DVD£¬ MP3£¬ and other audio equipments. <br><br><strong>Specifications:</strong> <br>Material: Acrylic and PVC <br>S/N: &gt;=90dB <br>Sensitivity: &lt;=230mV <br>Distortion: &lt;=0.1%(1kHz) <br>Frequency range: 20Hz - 500Hz <br>Impedance: 47ohm <br>Power adaptor: US Input: 220V 50Hz <br>???????????????? ? ? ? ? ? ?? Output: 12V 3A <br>Plug adaptor: EU 125/250V 6A <br>Item size: Approx.11 * 8 * 4cm / 4.3 * 3.1 * 1.6in <br>Item weight: 145g / 5.1oz <br>Package size: 20 * 14 * 4cm / 7.9 * 5.5 * 1.6in <br>Package weight: 408g / 14.4oz <br><br><strong>Package List:</strong> <br>1 * HiFi Amplifier <br>3 * Tube <br>1 * Power Adaptor(US) <br>1 * Plug Adaptor(EU) <br><br><strong>Note:</strong> <br>The HiFi amplifier should be assembled by yourself.