About the PAC AmpPRO AP4-FD21 Aftermarket Amplifier Interface
Your amp will sound better than the factory system
Your amp will sound better than the factory system
You can make a less-than-ideal factory system actually sound premium by upgrading the weak factory amplifier with a more powerful aftermarket amp. PAC's AmpPRO interface consists of a module and a vehicle-specific T-harness that make the job much easier. Now, you can install an amplifier of your own without losing any of your vehicle's factory audio features like warning chimes, navigation prompts, and Bluetooth functions.
Simple to install
The package's T-harness plugs into the factory radio and vehicle harness. The small module fits behind the dash, converting your radio's speaker outputs into six preamp-level outputs ready for connection to your amp. The factory amplifier needs to be left connected in the vehicle. The factory radio controls, such as volume, balance, and fade, will work as before for your front and rear speakers. A separate wired remote level control lets you adjust the volume of the subwoofer channels from your front seat. An optional add-on module, PAC's APA-TOS1 adapter, provides an optical digital output for your high-end digital processors and amplifiers to handle.
An app for tweakers
After downloading the AmpPRO PC App and connecting to your Windows-run PC via USB, you can access the factory 3-band parametric equalizer (EQ) and customize the tone of your system to perfection. The app also lets you adjust chime volume, the system's minimum volume level, and update the product firmware when needed.
Important Note: This AmpPRO interface simplifies the installation of a car amplifier (not included). You'll also need to purchase anything required to install your new amp: an amp wiring kit, speaker wire (to replace factory wiring), and RCA cables.
- amplifier integration module and T-harness
- add an aftermarket amplifier without removing factory amp
- works with select 2012-up Ford vehicles
- 6-channel RCA outputs (front, rear, subs)
- switchable 5- or 4-volt RMS output
- retains factory radio controls and audio features
- wired remote level control for sub channels
- remote turn-on lead for amplifiers
- AmpPRO PC App, available from PAC, lets you adjust minimum and chime volumes and 3-band EQ via your Windows-run PC
- optional TOSLINK adapter provides digital output
- warranty: 1 year
- Our 60-day money-back guarantee
- MFR # AP4-FD21
What's in the box:
PAC AmpPRO AP4-FD21 Aftermarket Amplifier Interface owner's manual
- Amplifier integration interface module
- 6' Rotary-knob cable
- Installation Instructions
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More details on the PAC AmpPRO AP4-FD21 Aftermarket Amplifier Interface
Amplifier Integration Interface: The PAC AmpPRO AP4-FD21 simplifies the installation of aftermarket amplifiers in select Ford vehicles with data-bus controlled factory sound systems. With the AmpPRO AP4-FD21, you can improve your vehicle's audio performance while keeping an original radio's fit, finish, and features.
- The factory radio and factory amplifier must remain connected in the vehicle and be operational in order to use the PAC AmpPRO interface.
- If you are only using the PAC AmpPRO interface to add a subwoofer amplifier, the factory amplifier will still power the other speakers in the vehicle.
Vehicle Compatibility: The PAC AmpPRO AP4-FD21 amplifier integration interface is compatible with the following 2013-2020 Ford vehicles with a data-bus controlled factory premium sound system.
Note: This interface is only compatible in vehicles equipped with a data-bus controlled premium sound system. To verify compatibility, look for a Sony badge on the door speakers, center speaker, or factory sub woofer. If this brand is not shown, check for the presence of a center speaker or subwoofer.
6Ch Pre-Outs: The PAC AmpPRO AP4-FD21 provides a 6-channel pre-amp output for use with aftermarket amplifiers. Using the full-range, fixed level factory radio output, in conjunction with data-bus CAN messages, the AP4-FD21 delivers a variable 5V RMS pre-amp output with fading, balance, equalization, and level control capabilities.
Non-Fading Level Control Knob: Channels 5-6 (Sub) of the AP4-FD21 are non-fading outputs. The output level of channels 5-6 can be controlled using the supplied level control knob. The level control knob comes with a 6' cable which plugs into the interface module and should be mounted in an accessible location.
Data Controlled Remote Turn-On: A data controlled remote amplifier turn on wire is also provided by the PAC AmpPRO AP4-FD21. The remote turn-on is rated at 2A of current. If more current is needed an external relay must be used.
Retained Factory Audio Features: The PAC AmpPRO AP4-FD21 also retains all audio from other vehicle features such as factory Navigation Prompts, Bluetooth, Sync, and Warning Chimes.
Minimum & Chime Volume: If the minimum volume of your factory radio is too loud once the AP4-FD21 is installed, you can manually set the level of the minimum volume using either the programming button on the side of the interface or the factory SWC (Steering Wheel Controls) in conjunction with the supplied level control knob. You can also use AmpPRO PC app. You can also adjust the chime volume level.
AmpPRO PC App: Using the AmpPRO PC App (for Windows PC only) allows you to configure user interface options such as Minimum Volume Level, Chime Volume Level, and a 3-Band EQ from your Windows computer or laptop. The app can also be used to update product firmware.
- Minimum & Chime Volume Level: From the app you can set the minimum volume level of the factory radio, as well as the chime volume level.
- 3-Band EQ: Enables the 3-band EQ (Bass-Mid-Treble) with frequency and Q-factory adjustment. The Bass Frequency can be set to 60, 80, 100, or 120Hz; while the Bass Q-Factor can be set to 0.5, 1.0, 1.5, or 2.0. The Mid Frequency can be set to 500, 1k, 1.5k, or 2.5k; while the Mid Q-Factor can be set to 0.75, 1.0, 1.25, or 1.5. The Treble Frequency can be set to 7.5k, 10k, 12.5k, or 15k; while the Treble Q-Factory can be set to 0.75 or 1.25.
- Firmware: The AmpPRO app will also allow you to update the interface with new firmware as it becomes available.
Note: These AmpPRO PC App settings can be adjusted with the module installed in the vehicle or on the bench. However, it is recommended to make the adjustments with the module installed, and the factory radio on so that the changes can be heard.
Dip Switch: Set dip switch 2 to "ON" to lower the RCA output voltage to 4V. Set the dip switch 2 "OFF" to keep the RCA output voltage at 5V. Dip switches 3-4 are used for troubleshooting Sync & Bluetooth. Dip switch 1 is not used.
Optional Toslink Add-On Module: When used in conjunction with PAC's APA-TOS1 (541APATOS1; sold separately), the AP4-FD21 can provide a variable 2-channel fiber optic digital audio output (toslink). Toslink fiber-optical cable also sold separately.
Optional Amplifier Harness: The APH-FD01 installation harness (541APHFD01, sold separately) simplifies speaker wire connections when using the PAC AmpPRO AP4-FD21 (sold separately) to add an aftermarket amplifier or amplifiers in select 2007-2017 Ford and Lincoln vehicles that feature factory amplified sound systems. The APH-FD01 keeps you from having to cut or modify your vehicle's original factory wiring, providing a direct connection at the vehicle's original factory amplifier location (you will need to make hardwire connections at the aftermarket amplifier/s).
20 questions already asked
Amazing product. Installed 3 of them so far for my clients with F-150's. If you have the chance to get the Optical Toslink output add-on module, do it! Your DSP will thank you. Can't recommend this unit enough.
Bryce H. from Virginia Beach, VA