Description
ARC Audio X2 450.4 — 4-Channel Class-D Amplifier
Choose the X2 450.4 when four clean channels solve the system and there is no reason to buy extra amplifier capacity the speakers will never use. This is the practical X2 starting point for factory-speaker upgrades, passive component sets, front/rear coaxials or a modest active layout where 85 watts × 4 at 4 ohms or 125 watts × 4 at 2 ohms is already the right power class.
Compared with the X2 600.4, the 450.4 gives up some channel power and configuration flexibility in exchange for a smaller, simpler system foundation. It still gives us bridgeable pairs, balanced inputs, speaker-level compatibility and automatic turn-on, so it works well when the factory radio stays and the goal is a real amplifier upgrade without overbuilding the rack.
Manufacturer Specifications
• Amplifier class: Class D
• Channels: 4
• Power output at 4 ohms: 85 watts × 4
• Power output at 2 ohms: 125 watts × 4
• Bridged power at 4 ohms: 250 watts × 2
• 2-ohm bridged operation: Not recommended
• Frequency response: 20 Hz–20 kHz
• Front crossover range: 50 Hz–3 kHz
• Rear high-pass range: 10 Hz–1 kHz
• Rear low-pass range: 50 Hz–3 kHz
• Crossover slope: 12 dB/octave
• Input sensitivity: 200 mV–3.5 V
• Fusing: 2 × 25 A
• Dimensions: 8.173 × 6.268 × 2.086 inches
• Input stage: Fully balanced
• RCA inputs: Speaker-level compatible
• Protection: Microprocessor-controlled with stored fault codes
• Automatic turn-on: Signal-sense and DC-detect
• Vehicle compatibility: Start/stop compatible
Choose the X2 450.4 when four clean channels solve the system and there is no reason to buy extra amplifier capacity the speakers will never use. This is the practical X2 starting point for factory-speaker upgrades, passive component sets, front/rear coaxials or a modest active layout where 85 watts × 4 at 4 ohms or 125 watts × 4 at 2 ohms is already the right power class.
Compared with the X2 600.4, the 450.4 gives up some channel power and configuration flexibility in exchange for a smaller, simpler system foundation. It still gives us bridgeable pairs, balanced inputs, speaker-level compatibility and automatic turn-on, so it works well when the factory radio stays and the goal is a real amplifier upgrade without overbuilding the rack.
Manufacturer Specifications
• Amplifier class: Class D
• Channels: 4
• Power output at 4 ohms: 85 watts × 4
• Power output at 2 ohms: 125 watts × 4
• Bridged power at 4 ohms: 250 watts × 2
• 2-ohm bridged operation: Not recommended
• Frequency response: 20 Hz–20 kHz
• Front crossover range: 50 Hz–3 kHz
• Rear high-pass range: 10 Hz–1 kHz
• Rear low-pass range: 50 Hz–3 kHz
• Crossover slope: 12 dB/octave
• Input sensitivity: 200 mV–3.5 V
• Fusing: 2 × 25 A
• Dimensions: 8.173 × 6.268 × 2.086 inches
• Input stage: Fully balanced
• RCA inputs: Speaker-level compatible
• Protection: Microprocessor-controlled with stored fault codes
• Automatic turn-on: Signal-sense and DC-detect
• Vehicle compatibility: Start/stop compatible
AMPLIFIER SYSTEM FIT
Where this fits in the build
An amplifier should be chosen around the channels, load, speaker or subwoofer plan, available electrical support and how hard the system needs to play.
Authorized Dealer — In-Store PurchasePlan aroundMatch usable channels and power to the actual speakers and load.
Match itPlan signal processing and gain structure before chasing wattage.
Finish itHigher output may require charging, battery and wiring upgrades.