The P1 can be used as a HiFi tube preamp, USB DAC and headphone amp. It also ensures HiFi clear, warm, dynamic, sweet tube sound and delivers an extremely high-quality listening experience [its 3.5mm headphone jack not for headphones with mic (TRRS port)] - Used as a headphone amp. With NE5532 op amp and classic 47 headphone amp structure, it can drive 32-300O headphones - Beautiful appearance and unique design.Blue and orange lights decorate the vacuum tubes; ideal for home and desktop speaker system - GE5654 vacuum tubes are used. They can be replaced by 6J1, 6J4, 6J5, 6AK5 and 61N to help you enjoy HiFi clear, warm, dynamic, sweet tube sound with your home theater system Attention: 1. The headphone output is given priority, and your headphone can adjust the volume. It is not for U disk to play music. Specifications: - Chip architecture: CM6642 + QCC3034+NE5532 + classic 47 - PC-USB input sampling frequency: 192K/24Bit - THD: 0.01% - Supported PC-USB system: For XP/Win 7/Win 8/Win 10/MAC/Linux - Bluetooth VER: 5.0 - Headphone matching impedance: 32-300O - Signal-to-noise ratio: 103dB - Headphone maximum power output: 160mW 32O load - Working voltage: DC12V - Bass and Treble Range: ±6dB - RCA output level: 2.3V - Frequency range: 20Hz-20kHz (±3dB) - Dimensions: 180 x 118 x 36mm/7.1 x 4.6 x 1.4 - Product weight: 0.47KG/1LB Package Included: - 1 x P1 Preamplifier - 2 x Vacuum Tubes - 1 x Power Adapter - 1 x USB Cable - 1 x Bluetooth Antenna - 1 x User Manual. Usually it cost about 35USD-50USD. If you receive defective item, please kindly notify us within 14 days. This item is in the category "Consumer Electronics\TV, Video & Home Audio\Home Audio\Receivers & Amplifiers\Amplifiers & Preamps". The seller is "pincei" and is located in this country: CN. This item can be shipped worldwide.