Q4

Product Specifications
Product Overview & Control Functions
Package Content
Quick Setup
Troubleshooting
Comparison Section
Warranty Information

Product Specifications

The Q4 is a compact mini digital/analog audio converter adapter with USB, optical, and coaxial digital inputs, a classic 3.5mm headphone jack, and RCA outputs, suitable for most home audio systems. It can be used as a preamplifier or volume control for PC/MAC/Computer with bass and treble controls. Fosi Audio Q4 ensures exquisite musicality, accurate and realistic phasing, and reproduction of the original sound!

Input Type:

USB, Optical, Coaxial

Output Type:

3.5mm Headphone, RCA

Chipset:

SA9023+CS8412+ 97220+NE5532

USB Sampling Rate:

24Bit/96kHz

Optical/Coaxial Sampling Rate:

24Bit/192kHz

Headphone Impedance:

16-200Ω

RCA Output Level:

2.3V

Power Supply:

5V

THD:

≤0.01%

SNR:

≥105dB

Size (L*W*H):

73.5*98*33MM

Net Weight:

0.4kg

Product Overview & Control Functions

Package Content

Fosi Audio DAC-Q4 ×1

5V USB Power Supply Cable ×1

PC-USB Cable ×1

Optical Cable ×1

User’s Manual ×1

Quick Setup

Preparation

PC-Windows, for example.

Prepared Q4, PC, AC adapter, PC-USB cable, Micro-USB cable, and headphones.

Step 1: Connect the Micro-USB cable to the AC adapter, then connect the Micro-USB cable to the Q4;

Step 2: Connect the Q4 to the PC via the PC-USB cable;

Step 3: Turn down the volume control to the lowest level (turn off the power switch) and connect the headphones to the 3.5mm headphone jack;

Step 4: Adjust the input mode selection key to select USB input mode;

Step 5: Turn on the power switch (turn up the volume); (Note: The power switch is also the volume control knob.

Turn on: Turn the volume knob clockwise to the right;

Turn off: Turn the volume knob counterclockwise to the left and adjust the volume to a minimum.)

Step 6: Left click on the computer’s desktop sound icon and select

Device: “Fosi Audio Q4″ (Digital HiFi Audio);

Step 7: Open the audio application, play it, and enjoy!

(Note: Before connecting the power supply, please turn down the volume control to the lowest level to avoid damage to your hearing.)

Optical for example

Prepare Q4, AC adapter, Micro-USB cable, optical device (TV, for example), and optical cable.

Step 1: Connect the Micro-USB cable to the AC adapter, then connect the Micro-USB cable to the Q4;

Step 2: Connect the TV to Q4’s optical interface via the optical cable;

Step 3: Adjust the input selection button to select optical mode;

Step 4: Set the TV’s optical output sound to RAW/PCM;

(NOTE: Due to different TV types, some TVs default Dolby or DTS sound output, Q4 DOES NOT Support Dolby and DTS sound, please select RAW/PCM Sound; otherwise, you will hear a lot of noise or no sound output.)

Step 5: Open the audio application, play and enjoy

Coaxial for example

Prepare Q4, AC adapter, Micro-USB cable, Coaxial device (TV, for example), Coaxial cable (no include).

Step 1: Connect the Micro-USB cable to the AC adapter, then connect the Micro-USB cable to the Q4;

Step 2: Connect the TV to Q4’s coaxial interface via the coaxial cable;

Step 3: Adjust the input selection button to select coaxial mode;

Step 4: Set the TV’s coaxial output sound to RAW/PCM;

(NOTE: Due to different TV types, some TVs default Dolby or DTS sound output, Q4 DOES NOT support Dolby and DTS sound, please select RAW/PCM sound; otherwise, you will hear a lot of noise or no sound output.)

Step 5: Open the audio application, play, and enjoy!

Troubleshooting

1: How do I power the DAC-Q4?

  • You will need to use the supplied Micro-USB cable to power it; we recommend using the PC-USB port/5V power adapter.

Note: The Micro-USB cable cannot be fully inserted into the device power port; please do not force it. Subsequent revisions have been made.

2: Why are all my wires plugged in, but the Q4 RCA analog output is silent?

  • At this point, you should check to see if the headphone output is plugged into the headphone. If so, you should unplug the headset to simulate RCA output.

3: Why do I get endless white noise?

  • Please check that your input device uses Dolby/DTS audio; please switch off Dolby/DTS audio and try again.

4: No Dolby/DTS audio, and I still get noise through the USB input?

  • Please switch the USB port to USB 3.0 or back USB port and try again, as some USB ports have unstable data transmission;
  • Please try again with another computer;
  • Please replace the PC-USB cable and retest, and contact us for compensation if the original cable is faulty;
  • Please change the power supply adaptation and retest; why? Because of the aging of the power supply, there may be an abnormal power supply resulting in white noise. We recommend using the PC-USB port/5V power adapter to power it.

5: Is a USB Device not recognized on Windows?

  • Select Start, then type device manager in the Search box, and then select Device Manager;
  • Expand Universal Serial Bus controllers. Press and hold (or right-click) a device and select Uninstall. Repeat for each device;
  • Once complete, restart your computer. Your USB controllers will automatically install.

If a Windows update causes the device to be unrecognized, please update all windows components, reboot, and retest. Please contact me for a solution.

6: How to do a plug-and-play on Windows?

  • Just click the sound icon in your notification area;
  • Click the “Select playback device” option;
  • Select the playback device “Fosi Audio Q4” (Digital HiFi Audio).

7: I can’t play Spotify music in Plug and Play mode?

  • Please exit the Spotify app and switch the playback device to the computer’s sound card device, open Spotify and play, confirm that it works, and then switch the playback device to DAC-Q4 “Digital HiFi Audio.”

8: How do I get the highest 24Bit/96kHz resolution on my PC?

  • Right-click the PC sound icon in the lower right corner, open Volume Mixer, click on the icon of the device/SPDIF: “Digital HiFi Audio” to open the Properties, click the Advanced, and select 24Bit, 96000Hz for maximum sound quality output.

9: Why do I get an intermittent sound?

  • Please switch the USB port to USB 3.0 or back USB port and try again, as some USB ports have unstable data transmission;
  • Please replace the PC-USB cable and retest; contact me for compensation if the original cable is faulty.

10: Why is there no sound when PC-USB connects to the PC?

  • First, press the PC-USB operation to confirm whether the digital playback output has been selected. If there is still no sound, you can restart the computer and repeat the process; please make sure you have chosen the correct device name on your PC sound setting.
  • Some computers’ USB ports are low quality on the front panel; please change the USB port to have a try; it’s better to use the USB port on the computer’s back panel.

11: Why is my device stopping working after a short time of use?

  • Ensure your audio source and the headphones, amplifier, or powered speakers you connected are working well. And please check all the connections of the input and output cables; please change the audio source, output devices, and cables to try again. Also, please check the power supply works or not.

 

Comparison Section

  • All Fosi Audio products have an 18-month limited warranty on parts and labor from the date of purchase. Please contact us if you have any problems.