Fosi Audio Q4 DAC Headphone Compact Mini Stereo Optical Digital Headphone Compatible with Supports Home Active Speakers Amplifier, 24-bit Amplifier,

【Important Notice for International Buyers – Tomoayax Premium Audio Hi-Fi Japan】

■ Voltage Compatibility This product is designed exclusively for use in Japan (AC 100V, 50/60Hz).

Many regions use 120V or 220–240V. Using this product without a proper transformer in such voltage environments may result in malfunction, overheating, or serious and irreversible damage.

■ Plug Type This product uses a Japanese plug (Type A or B). A plug adapter may be required depending on your region.

■ Transformer Requirement (Very Important) A transformer is required for safe use.

A plug adapter only changes the plug shape and DOES NOT convert voltage. Using this product without a transformer may cause serious and irreversible damage.

■ Buyer Responsibility As this is high-end audio equipment, the buyer is fully responsible for confirming compatibility with their local voltage (100V / 120V / 220–240V) and usage environment before purchase.

■ No Return / No Refund Policy We do NOT accept returns or refunds for: ・Voltage mismatch (including 120V and 220–240V environments) ・Use without a transformer ・Plug incompatibility ・Damage caused by improper setup or usage

■ Liability We are not responsible for any damage, malfunction, or performance issues caused by improper use or incorrect voltage conditions.

■ Final Notice Please ensure full understanding of the above before purchasing. Use only under the correct voltage environment. The Q4 DAC headphone amplifier is designed with RCA/PC-USB/optical/coaxial inputs, and its 3.5mm headphone output is compatible with most home audio systems and headphones. (Note: Microphone is not supported). The RCA output can be connected to a desktop amplifier or powered speakers. The built-in Hi-Fi headphone amplifier chip can drive headphones from 16 ohms to 200 ohms. The Q4 headphone USB DAC employs the Texas Instruments NE5532 high-performance operational amplifier chip, which combines excellent DC and AC characteristics. It features extremely low noise, high output drive capability, high unity amplification, and maximum output swing bandwidth, low distortion, high slew rate, input protection diodes, and output short-circuit protection. This 160mW RMS (32 Ω, 20 Hz - 20 kHz, 0.01% THD) digital audio adapter features bass and treble controls and can be used as a preamplifier or volume controller for PC/MAC/headphone/speaker systems. It's easy to set up and connect, requiring no separate software, apps, or drivers. This ultra-compact D/A converter features a full metal casing to guarantee high quality. It streams low-jitter, bit-perfect 24-bit/192kHz HD audio and includes output protection circuitry, making it safe for expensive audio systems. Shipping details: Q4 USB DAC x1, USB charging cable x1, optical cable x1, PC-USB to Type-B cable, user manual x1, 24-month warranty. If you have any questions about installing the product, please feel free to contact us. We will provide detailed guidance. Note: PC-USB supports input sampling rate: 96K/24Bit, high/low audio adjustment range: ±6dB. Fiber/coaxial support input sampling rate: 192K/24Bit, frequency response: 20Hz-20kHz (±3dB). PC-USB supports operating systems: XP/W7/W8/W10/MAC/Linux. Distortion: 0.01%. Operating voltage: DC5V. Amplifier output maximum power: 100mW with 32Ω load. Signal-to-noise ratio: ≥105dB. Headphone matching impedance: 16-200Ω.