SounDigital 4004EVOX4
SounDigital 400.4 EvoX2 4-Channel Vehicle Amplifier Instruction Manual
Model: 4004EVOX4
Introduction
Thank you for choosing the SounDigital 400.4 EvoX2 4-Channel Vehicle Amplifier. This manual provides essential information for the proper installation, operation, and maintenance of your amplifier. Please read it thoroughly before installation and use to ensure optimal performance and safety.
Safety Information
- Professional Installation Required: Installation of this amplifier should only be performed by qualified professionals to prevent damage to the unit or vehicle, and to ensure proper functionality.
- Power Disconnection: Always disconnect the vehicle's battery before performing any electrical work.
- Proper Wiring: Ensure all wiring is correctly connected and insulated to prevent short circuits and electrical hazards. Use appropriate gauge wires for power and speaker connections.
- Ventilation: Install the amplifier in a location with adequate ventilation to prevent overheating. Do not block cooling fins.
- Moisture and Heat: Avoid exposing the amplifier to moisture, water, or extreme temperatures.
- Secure Mounting: Mount the amplifier securely to prevent it from becoming a projectile in case of sudden stops or accidents.
What's in the Box
- SounDigital 400.4 EvoX2 4-Channel Vehicle Amplifier
- Instruction Manual (this document)
- Mounting Hardware (screws, etc. - assumed, not explicitly listed but typical)
Product Features
- 4-Channel Stereo Amplifier
- Full Range Amplifier: Suitable for subwoofers, woofers, midranges, drivers, and tweeters.
- RCA Input and High-Level Input with Automatic Remote: Eliminates the need for additional adapters for various head units.
- Integrated Crossovers: Features High-Pass Filter (HPF), Low-Pass Filter (LPF), and Full adjustments for precise frequency response tuning.
- Robust Power Connector: Ensures practical and safe installation.
- Wide Voltage Operation: Operates from 9V to 16V.
- Bridgeable Channels: Allows for bridging two channels to deliver higher power output.
Specifications
| Feature | Specification |
|---|---|
| Power @ 12.6V @ 4Ω | 4 x 66 WRMS |
| Power @ 12.6V @ 2Ω | 4 x 100 WRMS |
| Bridge Power @ 12.6V @ 4Ω | 2 x 200 WRMS |
| Power @ 14.4V @ 4Ω | 4 x 74 WRMS |
| Power @ 14.4V @ 2Ω | 4 x 112 WRMS |
| Bridge Power @ 14.4V @ 4Ω | 2 x 223 WRMS |
| Frequency Response (-3dB) | 5Hz – 22kHz |
| Crossover HPF | 45Hz – 850Hz |
| Crossover LPF | 45Hz – 850Hz |
| SNR | 88dB |
| Voltage | 9V - 16V (Operating) |
| Maximum Supply Voltage | 16 Volts |
| Minimum Supply Voltage | 8 Volts |
| Supply Current | 19 Amps |
| Number of Channels | 4 |
| Mounting Type | Surface Mount |
| Product Dimensions | 4.8 x 4.4 x 2.0 inches |
| Item Weight | 1.47 pounds |
Setup and Installation
Note: Professional installation is highly recommended for this product.
1. Mounting the Amplifier
Choose a dry, well-ventilated location in your vehicle, away from direct heat sources and moisture. Ensure the mounting surface is stable and secure. Use the provided mounting hardware to firmly attach the amplifier.

2. Power Connections
- Power (+12V): Connect a suitable gauge power cable from the vehicle's positive battery terminal (with an inline fuse) to the +12V terminal on the amplifier.
- Ground (GND): Connect a short, heavy-gauge ground cable from the GND terminal on the amplifier to a clean, unpainted metal surface on the vehicle chassis.
- Remote (REM): Connect a remote turn-on wire from your head unit's remote output to the REM terminal on the amplifier. If using high-level input, the amplifier may feature automatic remote turn-on.

3. Audio Input Connections
- RCA Input: For head units with RCA pre-outs, connect RCA cables from the head unit to the amplifier's RCA input jacks (CH1-CH2, CH3-CH4).
- High-Level Input: If your head unit does not have RCA outputs, use the high-level input. Connect the speaker wires from your head unit directly to the high-level input connector on the amplifier. The amplifier will automatically detect the audio signal and turn on.

4. Speaker Connections
Connect your speakers to the output terminals (CH1, CH2, CH3, CH4). Ensure correct polarity (+ to + and - to -). For bridged mode, refer to the markings on the amplifier for the correct terminals (Bridge 4Ω).

Operating the Amplifier
1. Gain Adjustment
The gain controls (MIN/MAX) adjust the input sensitivity of the amplifier. Start with the gain set to minimum. Play a familiar audio track at about 75% of your head unit's maximum volume. Slowly increase the amplifier's gain until you hear distortion, then back off slightly. This ensures the amplifier is receiving a clean signal without clipping.
2. Crossover Settings
The SounDigital 400.4 EvoX2 features integrated crossovers to optimize sound output for different types of speakers:
- HPF (High-Pass Filter): Allows frequencies above the set point (45Hz – 850Hz) to pass through. Use for tweeters or full-range speakers to prevent low frequencies that can cause distortion.
- LPF (Low-Pass Filter): Allows frequencies below the set point (45Hz – 850Hz) to pass through. Use for subwoofers or woofers.
- FULL: Disables the crossover, allowing the full frequency range to pass through. Use for full-range speakers or if an external crossover is being used.
Adjust the crossover frequency according to your speaker's specifications and your desired sound profile.

3. Bridged Mode Operation
For higher power output to a single speaker (e.g., a subwoofer), the amplifier can be operated in bridged mode. This combines two channels into one. Refer to the amplifier's output terminals for specific bridged connection points (Bridge 4Ω). Ensure the connected speaker's impedance is compatible with the bridged output (minimum 4Ω).

Maintenance
- Cleaning: Regularly clean the amplifier's exterior with a soft, dry cloth. Do not use harsh chemicals or abrasive cleaners.
- Ventilation: Ensure the cooling fins remain free of dust and debris to maintain proper heat dissipation.
- Connections: Periodically check all power, ground, and speaker connections to ensure they are secure and free from corrosion.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No Power | Blown fuse, loose power/ground connection, no remote signal. | Check and replace fuse, verify all power and ground connections are secure, ensure remote wire is connected and receiving signal. |
| No Sound Output | Loose RCA/high-level input, incorrect speaker wiring, gain set too low, head unit issue. | Check input connections, verify speaker polarity and connections, adjust gain, test head unit with another amplifier if possible. |
| Distorted Sound | Gain set too high, incorrect crossover settings, speaker impedance mismatch, damaged speakers. | Reduce gain, adjust crossover settings, verify speaker impedance matches amplifier's capabilities, inspect speakers for damage. |
| Amplifier Overheating | Insufficient ventilation, impedance too low, prolonged high-volume use. | Ensure adequate airflow around the amplifier, check speaker impedance, reduce volume or allow cooling time. |
Product Videos
Taramps DS 440X4 Multi-Channel Amplifier Overview
This video provides an overview of a similar 4-channel amplifier from Taramps, demonstrating features and capabilities common to compact multi-channel car audio amplifiers. While not the exact SounDigital model, it offers valuable insights into the functionality and installation of such devices.
400W Full Range Car Audio Amplifier Demonstration
Watch this video for a demonstration of a 400W full-range amplifier, showcasing its power and suitability for various car audio setups. This provides a general understanding of the performance you can expect from a compact, high-power amplifier.
Warranty and Support
For warranty information, technical support, or service inquiries, please refer to the manufacturer's official website or contact your authorized SounDigital dealer. Keep your purchase receipt as proof of purchase for warranty claims.
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