Package:
1*DAC Headphone Amplifier
No power adapter included
Usage Instructions:
1. The A39 adopts single DC 12V power supply. The power socket specification is 5.5*2.1mm (Positive Inside, Negative Outside). For better sound quality, a high-grade linear power supply is recommended.
2. Short-press the A39's knob to switch inputs, and rotate it to adjust the volume. On the panel:
"B" indicates Bluetooth/USB Input
"O" indicates Optical Input
"C" indicates Coaxial Input
The device has a 4.7x gain, compatible with both in-ear monitors and full-size headphones.
3. The Bluetooth name is "YJHIFI/ YJCO". Search for and connect with your mobile phone, then switch to Bluetooth Input to start playback.
4. The USB Input is routed through the Bluetooth module. To use USB Input:
① Switch to Bluetooth Input mode first
② Cancel Bluetooth pairing
③ Insert the USB cable,
Note: Use a data-transmitting OTG USB cable. Charging-only cables will not be recognized. The USB port cannot be used with a USB flash drive.
5. The rear RCA Output is a direct decoded output (bypassing the potentiometer volume control), designed for connection to a power amplifier or preamplifier.
