Zavedení
The PAC LPA-E.4 is a 4-channel line-output converter designed to integrate aftermarket amplifiers with factory audio systems. It converts high-level speaker outputs from a factory radio into low-level RCA signals, providing a clean and adjustable signal for your amplifier. This manual provides detailed instructions for installation, operation, and troubleshooting to ensure optimal performance of your LPA-E.4 unit.
Vlastnosti produktu
- Durable aluminum housing for enhanced heat dissipation and longevity.
- Supports up to 40V / 400W maximum input at 20kΩ.
- Integrated low-pass filter for channels 3 and 4 (CH3/4 only).
- Selectable bass boost for channels 3 and 4 (CH3/4 only).
- Dual variable gain controls for precise output level matching.
- Selectable ground common, isolated, or 200Ω ground options.
- Multiple load selections: 20Ω, 60Ω, 20kΩ.
- Clip indicators for both front and rear channels to prevent distortion.
- Turn-on mode selection: remote or DC offset.
- Provides up to 9.5V output voltage.
- Removable quick-connect terminal block with screw-type terminals for easy wiring.
- Wide range DC offset detection.
- Flexible input configuration: 4-channel input to 4-channel unfiltered output or 2-channel input to 4-channel unfiltered output.
Bezpečnostní informace
Always disconnect the vehicle's battery before beginning any installation. Ensure all wiring is properly insulated and secured to prevent short circuits and damage. Consult a professional if you are unsure about any part of the installation process. Do not operate the unit in wet conditions or expose it to extreme temperatures.
Instalace a nastavení
Proper installation is crucial for the optimal performance of your LPA-E.4. Follow these steps carefully.
1. Umístění jednotky
Mount the LPA-E.4 in a dry, secure location away from direct heat sources and moisture. Ensure adequate ventilation around the unit. The aluminum housing is designed for heat dissipation, but proper airflow is still recommended.
2. Připojení vodičů
The LPA-E.4 features a removable quick-connect terminal block for high-level inputs and power connections. RCA outputs are provided for low-level signals to your ampživější.
- 12V: Připojte k spínanému zdroji napájení 12V.
- GND: Připojte k pevnému uzemňovacímu bodu na podvozku.
- PŘIPOMENUTÍ: Connect to the remote turn-on wire from your head unit (if using remote turn-on mode).
- ODSTRANIT: Provides a remote turn-on signal for your ampživější.
- FL+, FL-: Front Left speaker input from factory radio.
- FR+, FR-: Front Right speaker input from factory radio.
- RL+, RL-: Rear Left speaker input from factory radio.
- RR+, RR-: Rear Right speaker input from factory radio.
Connect the RCA cables from the LPA-E.4's "FRONT OUTPUT" and "REAR OUTPUT" to the corresponding inputs on your aftermarket ampživější.
3. Ovládací panel Overview
Familiarize yourself with the controls on the LPA-E.4 unit. The image below illustrates the various switches and adjustments.

Úhlové view of the PAC LPA-E.4 4-Channel Line-Output Converter, showing its input terminals, control switches, gain knobs, clip indicators, and RCA outputs.
- INPUT MODE (2CH/4CH): Selects whether the unit processes 2 or 4 input channels. Use 2CH if your factory radio only provides 2 full-range channels and you need 4 outputs. Use 4CH if your factory radio provides 4 distinct channels.
- LOAD SELECT (20Ω, 60Ω, 20kΩ): Adjusts the input impedance to match the factory radio's output. Experiment with settings to find the best sound quality and to ensure the factory radio does not detect an open circuit.
- LPF (ON/OFF): Activates or deactivates the low-pass filter for channels 3 and 4. When ON, it filters out high frequencies, typically used for subwoofer applications.
- TURN ON (DC/REM): Selects the method for turning the unit on.
- DC: The unit turns on automatically when it detects a DC offset on the speaker inputs (from the factory radio turning on).
- REM: The unit turns on via the REM IN wire connected to a remote turn-on signal from the head unit.
- GROUND (GND/ISO/200Ω): Provides options for ground isolation to help eliminate ground loop noise.
- GND: Společná půda.
- ISO: Isolated ground.
- 200Ω: 200 Ohm ground isolation.
- BOOST (0dB/12dB): Activates or deactivates a 12dB bass boost for channels 3 and 4. Use with caution to avoid distortion.
- ZESILENÍ (MIN/MAX): Dual variable gain controls (one for front, one for rear) allow you to match the output level of the LPA-E.4 to the input sensitivity of your amplifier. Adjust these to achieve maximum clean output without clipping.
- Indikátory CLIP: Independent clip indicators for front and rear channels illuminate when the output signal is clipping, indicating distortion. Reduce the gain if these indicators light up during playback.
- FRONT OUTPUT / REAR OUTPUT: RCA outputs for connecting to your ampživější.
Operace
Once installed, the LPA-E.4 operates automatically based on your chosen turn-on mode. The primary operational adjustments involve setting the gain levels and selecting appropriate filter and ground settings.
- Počáteční zapnutí: Turn on your vehicle's ignition and factory radio. The LPA-E.4 should power on according to your selected TURN ON mode.
- Úprava zisku:
- Nastavte si svůj ampzesílení zařízení Liferier na minimální nastavení.
- Play a test tone (e.g., a 1kHz sine wave for full-range, 50Hz for subwoofers) at a moderate volume on your factory radio (around 75% of maximum).
- Slowly increase the GAIN controls on the LPA-E.4 until the corresponding CLIP indicator just begins to flicker. Then, slightly reduce the gain until the clip indicator remains off.
- Repeat for both front and rear channels.
- Upravte si svůj amplifier's gain to achieve desired volume levels without distortion.
- Filter and Boost Settings:
- If using channels 3/4 for a subwoofer, set the LPF switch to ON.
- If additional bass emphasis is desired for channels 3/4, activate the BOOST switch. Monitor for distortion.
- Ground Loop Noise: If you experience humming or whining noises, adjust the GROUND switch through its settings (GND, ISO, 200Ω) to find the one that minimizes or eliminates the noise.
Odstraňování problémů
| Problém | Možná příčina | Řešení |
|---|---|---|
| Žádný zvukový výstup. | No power to LPA-E.4; incorrect input mode; gain too low; ampZáchranář se nezapíná. | Check 12V and GND connections. Verify TURN ON mode and REM IN/DC offset. Ensure INPUT MODE matches wiring. Increase GAIN. Check ampnapájení záchranáře a dálkové zapnutí. |
| Zkreslený zvuk. | Gain set too high (clipping); incorrect LOAD SELECT; BOOST engaged excessively. | Reduce GAIN until CLIP indicator is off. Adjust LOAD SELECT. Disengage or reduce BOOST. |
| Engine noise or hum. | Ground loop interference. | Adjust the GROUND switch (GND, ISO, 200Ω) to find the quietest setting. Ensure a solid chassis ground connection. |
| LPA-E.4 not turning on. | Incorrect TURN ON mode; no remote signal; no DC offset detected. | Verify 12V and GND connections. Check TURN ON switch setting. If using REM, ensure REM IN receives a signal. If using DC, ensure factory radio outputs DC offset. |
Specifikace
- Model: LPA-E.4
- kanály: 4-channel input, 4-channel output
- Maximální vstupní objemtage: 40 voltů
- Maximální příkon: 400 Watts @ 20kΩ
- Výstupní objemtage: Up to 9.5 Volts
- Materiál: Hliníkové pouzdro
- Hmotnost položky: Přibližně 16 unce (1 libry)
- Rozměry balení: 8 x 5.8 x 1.3 palce
- Výrobce: PAC
Záruka a podpora
For specific warranty information, please refer to the warranty card included with your purchase or visit the official PAC website. For technical support or further assistance, please contact PAC customer service directly. Keep your proof of purchase for warranty claims.





