1. Introduction
The Douk Audio T7 is a high-performance 7-band equalizer and preamplifier designed to enhance your home audio system. It features both balanced XLR and single-ended RCA inputs and outputs, allowing for versatile connectivity with various audio components. With its independent frequency band controls, the T7 enables precise sound customization to compensate for speaker characteristics and room acoustics, delivering a tailored listening experience.
2. Safety Information
- Ensure the power adapter is correctly connected to the DC 12V input. Use only the provided power adapter or a compatible replacement with the correct voltage and current rating.
- Do not expose the unit to water, moisture, or extreme temperatures.
- Avoid placing the unit in direct sunlight or near heat sources.
- Do not open the casing; there are no user-serviceable parts inside. Refer all servicing to qualified personnel.
- Keep the unit away from strong magnetic fields.
- Ensure proper ventilation around the unit to prevent overheating.
3. Package Contents
Please check the package carefully for the following items:
- 1x Douk Audio T7 Preamplifier
- 1x DC 12V Power Adapter
Figure 3.1: Package Contents and Dimensions
4. Product Overview
4.1 Front Panel Controls
Figure 4.1: Front Panel Layout
- Input Selector / Power Knob: Selects between RCA input, Balanced (BAL) input, or powers the unit OFF (which also activates bypass mode).
- 64Hz Adjustment Knob: Controls the gain for the 64Hz frequency band.
- 125Hz Adjustment Knob: Controls the gain for the 125Hz frequency band.
- 250Hz Adjustment Knob: Controls the gain for the 250Hz frequency band.
- 500Hz Adjustment Knob: Controls the gain for the 500Hz frequency band.
- 2KHz Adjustment Knob: Controls the gain for the 2KHz frequency band.
- 4KHz Adjustment Knob: Controls the gain for the 4KHz frequency band.
- 8KHz Adjustment Knob: Controls the gain for the 8KHz frequency band.
4.2 Rear Panel Connections
Figure 4.2: Rear Panel Layout and Connection Diagram
- Balanced XLR Input: For connecting audio sources with XLR outputs.
- RCA Input: For connecting audio sources with RCA outputs.
- Balanced XLR Output: For connecting to amplifiers or active speakers with XLR inputs.
- RCA Output: For connecting to amplifiers or active speakers with RCA inputs.
- DC 12V IN: Power input for the included DC 12V power adapter.
5. Setup Instructions
Follow these steps to set up your Douk Audio T7 equalizer:
- Placement: Place the T7 on a stable, flat surface, ensuring adequate ventilation around the unit.
- Connect Audio Sources: Connect your audio source devices (e.g., MP3 player, phone, tablet PC, CD/DVD player, TV/set-top box, laptop/computer) to the T7's input. You can use either the Balanced XLR Input or the RCA Input.
- Connect to Amplifier/Speakers: Connect the T7's output to your amplifier or active speakers. You can use either the Balanced XLR Output or the RCA Output.
- Power Connection: Connect the provided DC 12V power adapter to the 'DC 12V IN' port on the rear panel of the T7, then plug the adapter into a wall outlet.
- Initial Power On: Turn the Input Selector / Power knob to either 'RCA' or 'BAL' to power on the unit and select your desired input.
Figure 5.1: Typical Connection Diagram
6. Operating Instructions
The Douk Audio T7 allows for precise control over your audio's frequency response.
- Power On and Input Selection: Rotate the leftmost knob to select your audio input (RCA or BAL). This action also powers on the unit.
- Adjusting Equalization: Use the seven individual frequency adjustment knobs (64Hz, 125Hz, 250Hz, 500Hz, 2KHz, 4KHz, 8KHz) to boost or cut the gain for each specific frequency band. Each knob offers a range of -6dB to +6dB. Adjust these to tailor the sound to your preference, compensate for room acoustics, or correct speaker deficiencies.
- Bypass Mode: To listen to the original, unprocessed sound, turn the Input Selector / Power knob to the 'OFF' position. This activates the bypass mode, allowing the audio signal to pass through without equalization.
- Output: Both XLR and RCA outputs function simultaneously, allowing you to connect to multiple devices if needed.
Figure 6.1: Adjusting the 7-band Equalizer
Figure 6.2: Bypass Mode Activation
7. Maintenance
- Cleaning: Use a soft, dry cloth to clean the exterior of the unit. Do not use liquid cleaners or aerosols.
- Dust: Regularly dust the unit to prevent accumulation, which can affect performance and cooling.
- Connections: Periodically check all cable connections to ensure they are secure and free from corrosion.
- Storage: If storing the unit for an extended period, disconnect it from power and store it in a cool, dry place.
8. Troubleshooting
If you encounter issues with your Douk Audio T7, please refer to the following common troubleshooting steps:
- No Power: Ensure the DC 12V power adapter is securely connected to both the unit and a working power outlet. Check if the input selector knob is set to 'RCA' or 'BAL' (not 'OFF').
- No Sound:
- Verify all audio cables (input and output) are correctly and securely connected.
- Confirm the audio source is playing and its volume is adequate.
- Check the amplifier or active speaker's power and input selection.
- Ensure the T7's input selector is set to the correct input (RCA or BAL).
- Distorted Sound:
- Check if any of the EQ knobs are set to extreme positions. Try returning them to the center (0dB) position.
- Ensure the input signal level from your source is not too high, causing clipping.
- Verify that all cables are in good condition and properly connected.
- Humming/Noise:
- Ensure all audio components are properly grounded.
- Try separating power cables from audio cables to reduce interference.
- Test with different cables or power outlets.
If the problem persists, please contact Douk Audio customer support.
9. Specifications
| Feature | Specification |
|---|---|
| Model | Douk Audio T7 |
| Audio Input | Single-ended RCA / Balanced XLR |
| Audio Output | Single-ended RCA / Balanced XLR |
| Frequency Response | 20Hz～20KHz (±1dB) |
| Frequency Bands | 64Hz / 125Hz / 250Hz / 500Hz / 2KHz / 4KHz / 8KHz |
| RCA Input Sensitivity | 0.775Vrms |
| RCA Output Level | 1.2Vrms |
| BAL Input Sensitivity | 1.5Vrms |
| BAL Output Level | 3Vrms |
| THD (Total Harmonic Distortion) | 0.003% |
| SNR (Signal-to-Noise Ratio) | ≥104dB |
| Working Voltage | DC12V (≥1.5A) |
| Dimensions (W*D*H) | 152*126*42mm / 5.98*4.96*1.65in |
| Net Weight | 700g / 1.54lb |
| Package Weight | 1.0kg / 2.20lb |
| Channels | 2 (2.0) |
| Maximum Power Per Channel | NO POWER (Preamplifier/Equalizer) |
10. User Tips
- The T7 does not have a dedicated volume control knob. It outputs at a rated level. Volume control should be managed by your connected amplifier or active speakers.
- Both the XLR and RCA outputs operate simultaneously. This allows for flexible connectivity options, such as connecting to an amplifier via XLR and a separate recording device via RCA at the same time.
- Experiment with the EQ settings in small increments. Drastic changes can sometimes lead to unnatural sound. Listen critically and adjust to achieve a balanced and pleasing audio profile.
11. Warranty and Support
The Douk Audio T7 comes with a 2-year warranty from the date of purchase, covering manufacturing defects. Please retain your proof of purchase for warranty claims.
For technical support, troubleshooting assistance, or warranty inquiries, please contact Douk Audio customer service through their official website or the retailer where the product was purchased.
