PAC Audio AP4-FD21:

• Interface module that allows the replacement or addition of an amplifier
• Compatible only with vehicles equipped with data bus premium sound system
• Variable volume, fade, balance, bass, mid and treble audio settings
• Front, rear, sub preamp outputs (5 volt RMS)
• 5 channel RCA output
• Amplifier turn-on trigger wire
• Non-fading level control knob
• Flat audio output for solid foundation
  
• Provides flat audio output for a solid audio foundation
• Customized OE bass, mid and treble center frequency selection
• Retains SYNC, Bluetooth audio and all warning chimes
• Plug & play installation
• Sub level controller
• Simplifies amplifier installation
• Prevents need for summing and DSP devices
• Provides factory sound system upgrade solution
• Additional harness features: Ford Sync Retention
• Chime Retention: Yes
  

Benefits:

• Simplifies amplifier installation
• Prevents need for summing and DSP devices
  
• Provides factory sound system upgrade solution

PAC Audio APA-TOS1:

Product Features:

• Quick and easy installation into any AmpPRO (interfaces not included):
  AP4-CH31, AP4-CH21, AP4-CH41, or AP4-FD21
• Provides a digital fiber-optic variable audio signal output
• Compatible with TOSLINK equipped DSPs or amplifiers
• Digital audio signals are less susceptible to noise or interference

Compatibility requirements & notes to consider

• Professional installation is strongly advised.
• TOSLINK cable is not included.
• Just for use in conjunction with an  AP4 interface.
• The installation of this product requires the disassembly of the AP4 interface.
• The audio component to be used with the APA-TOS1 must be equipped with a TOSLINK fiber optic audio input.  (S/PDIF 2 channel uncompressed PCM audio)