1. Introduction
The TEYUN AF4 is a professional 4-channel USB mixer and sound card designed for computer recording, studio use, and live webcasting. It integrates an analog mixing console with digital sound card capabilities, offering a flexible LOOPBACK function and LXR combination microphone input interfaces. This manual provides detailed instructions for setting up, operating, and maintaining your AF4 mixer to ensure optimal performance and longevity.
Front view of the TEYUN AF4 mixer, showing all controls and ports.
2. Setup
2.1 Package Contents
- 1 x TEYUN AF4 Sound Card/Mixer
- 1 x Power Adapter (EU Plug or US Plug, depending on region)
2.2 Power Connection
Connect the provided AC100-240V power adapter to the DC 5V/2A input on the mixer and then to a suitable power outlet.
2.3 Audio Connections
The AF4 mixer offers a variety of input and output options:
Detailed view of the mixer's input and output section.
- Microphone Inputs (Channels 1 & 2): Use XLR or 1/4" TRS cables to connect microphones. The mixer features LXR combination input interfaces.
- Line Inputs (Channels 3 & 4): Use 1/4" TRS cables for line-level instruments or devices.
- Tape In (REC): Use RCA cables to connect external audio sources for playback.
- Main Outputs (L/R): Connect to your main speakers or amplifier using 1/4" TRS cables.
- AUX Output: For sending audio to external effects processors or monitoring systems.
- EFFECT Output: Dedicated send for external effects.
- Headphones Output: Connect your headphones for monitoring.
Example of connecting an XLR microphone to the mixer.
2.4 Computer Connection (USB)
Connect the mixer to your computer using a USB cable. The AF4 features a built-in sound card that supports two-way audio transmission (USB output to computer, computer sound to mixer) without requiring driver installation for most software.
The AF4 mixer connected to a laptop via USB, demonstrating its sound card functionality.
3. Operating Instructions
3.1 Channel Controls
Each input channel (1, 2, and 3/4 stereo pair) has the following controls:
- GAIN: Adjusts the input sensitivity for the connected microphone or line device.
- HIGH, MID, LOW (EQ): Three-band equalizer to shape the tone of the input signal.
- EFX: Controls the amount of signal sent to the internal effects processor or external effect send.
- AUX: Controls the amount of signal sent to the AUX output.
- PAN: Adjusts the stereo positioning (left to right) of the channel.
- VOL: Adjusts the individual channel's volume level.
3.2 Master Section Controls
- CLIP / 0 / -24 Indicators: Visual indicators for signal level, helping to prevent clipping.
- POWER Indicator: Shows the power status of the unit.
- +48V PHANTOM Switch: Activates +48V phantom power for condenser microphones connected to XLR inputs. Ensure this is off before connecting/disconnecting microphones.
- USB / MP3 / BT / PC MODE Selector: Selects the audio source for the master section (USB drive, Bluetooth, or PC audio via USB).
- USB Playback Controls: VOL-, VOL+, Play/Pause, Next, Previous, Mode buttons for controlling audio playback from a USB drive.
- DELAY / REPEAT: Knobs to adjust the parameters of the built-in delay effect.
- AUX / EFX / MAIN / PHONES Volume Knobs: Master volume controls for Auxiliary output, Effects return, Main mix output, and Headphones output, respectively.
Controls for USB playback function.
3.3 Loopback Function
The flexible LOOPBACK function allows you to record the mixed output of the mixer directly back into your computer, making it ideal for recording and webcasting applications where you need to capture both your microphone and computer audio simultaneously.
3.4 Bluetooth Connectivity
The AF4 features built-in wireless Bluetooth for quick connection to compatible devices. Select 'BT' mode and pair your device to stream audio wirelessly to the mixer.
Demonstration of Bluetooth connection with a smartphone.
4. Maintenance
- Cleaning: Use a soft, dry cloth to clean the exterior of the mixer. Avoid using abrasive cleaners or solvents.
- Storage: Store the mixer in a cool, dry place away from direct sunlight and extreme temperatures.
- Cable Management: Ensure all cables are neatly organized and not under strain to prevent damage to connectors and ports.
5. Troubleshooting
- No Sound Output:
- Check all audio cable connections to ensure they are secure.
- Verify that the main volume, channel volume, and headphone volume knobs are turned up.
- Ensure the correct input source (USB, MP3, BT, PC) is selected in the master section.
- If using phantom power, ensure the +48V switch is engaged for condenser microphones.
- Distorted Sound:
- Reduce the GAIN knob on the input channel.
- Check the CLIP indicators; if they are frequently lighting up, reduce the input level.
- Ensure the main output volume is not too high, causing distortion in connected speakers/amplifiers.
- USB Not Recognized by Computer:
- Try connecting to a different USB port on your computer.
- Ensure the mixer is powered on.
- Verify that the USB cable is not damaged.
- Select 'PC' mode on the mixer.
- Bluetooth Pairing Issues:
- Ensure the mixer is in 'BT' mode.
- Make sure Bluetooth is enabled on your device and it's discoverable.
- Try restarting both the mixer and your Bluetooth device.
6. Specifications
6.1 Audio Specifications
Detailed specifications for input channels and stereo track.
| Feature | Specification |
|---|---|
| Microphone Input (Channels 1-5) | Electronic balanced discrete input configuration |
| Frequency Response (Mic) | 10Hz to 200kHz |
| Gain Span (Mic) | +14 dB to +60 dB |
| Signal-to-Noise Ratio (Mic) | 120 dB E.I.N. |
| Line Input (Channels 1-5) | Electronically balanced |
| Frequency Response (Line) | 10Hz to 130kHz |
| Gain Span (Line) | -6 dB to +38 dB |
| Signal-to-Noise Ratio (Line) | 95 dB E.I.N. |
| Stereo Track Frequency Response | 10 Hz to 70 KHZ |
| Stereo Track Gain Span (Line) | -8 to +15 dB |
| Stereo Track Gain Span (Microphone) | +13 to +60 dB |
| Stereo Track Signal-to-Noise Ratio (Line) | 96 dB |
| Stereo Track Signal-to-Noise Ratio (Microphone) | 104 dB E.I.N. |
6.2 Equalization & Output
Detailed specifications for equalization and mixed outputs.
| Feature | Specification |
|---|---|
| Low EQ | 50 Hz, +/-15 dB |
| Middle EQ | 700 Hz, +/-15dB |
| High EQ | 10 kHz, +/- 15 dB |
| Main Output | +28 dBu Balance / +22 dBu balance |
| Auxiliary Output | +22 dBu balance |
| EFF Output | +22 dBu balance |
| Tape Output | +22 dBu balance |
| Moving Output | +15 dBu/150 |
6.3 General Specifications
| Feature | Specification |
|---|---|
| Power Supply | DC 5V/2A |
| Color | Black |
| Material | Plastic |
| Dimensions (L x W x H) | 20.5cm x 20cm x 4cm |
Top and side dimensions of the TEYUN AF4 mixer.
7. User Tips
- Gain Staging: Always set your input GAIN levels carefully to achieve a strong signal without clipping. Watch the CLIP indicators on each channel and the master section.
- Loopback for Streaming: When webcasting or recording, utilize the LOOPBACK function to easily capture all audio playing on your computer along with your microphone inputs.
- Experiment with Effects: The built-in DELAY and REPEAT effects can add depth to vocals or instruments. Experiment with the knobs to find the desired sound.
- Microphone Compatibility: The mixer supports both dynamic and condenser microphones. Remember to activate +48V PHANTOM power only for condenser microphones.
- Versatile Connectivity: The AF4 is compatible with a wide range of audio devices, including wireless microphones, guitars, amplifiers, and electronic organs.
The TEYUN AF4 mixer is compatible with a variety of audio devices.
8. Warranty and Support
For warranty information and technical support, please refer to the documentation provided at the time of purchase or contact your retailer. Keep your proof of purchase for any warranty claims.
