Feature: 1. UNIQUE DESIGN: compact and adaptable, connected to active speakers through RCA to improve sound quality, or used as a powerful headphone amplifier. Note: DAC volume adjustment is only applicable to headphones. When the DAC is working, the earphone and RCA output will emit sound at the same time. 2. EXCLUSIVE CUSTOMIZED ADVANCED CHIP: The digital decoding chip adopts the JITTER chip produced by Ti company in the United States. It uses a high power, low loss true independent power amplifier circuit to easily drive 300 ohm headphones. It uses Alarge heating resistors and capacitors to provide excellent sound quality. 3. MULTIPLE INPUT AND OUTPUT METHODS: the power amplifier can be PC USB, optical fiber, coaxial three way input, can be connected to TV set top box, DVD, DCD, output mode has RAC, a 6.35mm headphone port, can be connected to power amplifier, vacuum tube power amplifier, active Speakers. 4. EFFICIENT PROTECTION AND LONG LIFE: The audio decoder uses a dedicated operational amplifier designed for audio. The op amp can be freely replaced and upgraded. At the same time, the relay protector can protect earphones and speakers. 5. SEALED STEPPING POTENTIOMETER: The electric positioner is an imported advanced sealed stepping potentiometer, and the rotation resistance is just right. Calculate as arc wiring to avoid current failure caused by static electricity at the leading edge. Analog point grounding, strictly follow the definition of analog grounding. 6. PLAY MUSIC: When you use it to listen to music, it can bring you wonderful music enjoyment. DAC is also very suitable for FPS games. It can use and direct sound perfectly. You can turn off active speakers or amplifiers as needed. Specification: Item Type: USB Coaxial Digital Audio Amplifier Material: Metal Model: P90 Color: Blue Function: USB / Coaxial / for Toslink Digital Audio Signal Conversion To 6.35mm Earphone And Analog L/R Audio Applicable Scenarios: Home, Office, Etc. Output Audio: L/R Audio And 6.35mm Earphone Sampling Rate: 32,44.1, 48.96, 192 Khz Working Temperature: 0°C To +70°C. Package List: 1 x Decoder1 x Power Adapter1 x 6.35mm to 3.5mm Cable1 x For Toslink Cable1 x USB Cable1 x Manual Note: Please allow 0‑1mm / 0‑0.04in error due to manual measurement. Thanks for your understanding.