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Discontinued Infinity 4-Channel Amplifiers

Perfectly balance your audio with Infinity 4-Channel Amplifiers for a harmonious sound.

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Infinity Reference 704A

1000W Peak (400W RMS) Reference Series 4-Channel Amplifier

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1000W Peak (400W RMS) Reference Series 4-Channel Amplifier

• 70 Watts RMS x 4 @ 4 ohm
• 100 Watts RMS x 4 @ 2 ohm
• Total Peak Power: 1000 Watts
• Variable Bass Boost: 0 to +9 dB
• Heavy duty aluminum alloy heat-sink for extreme heat dissipation
• Frequency Response: 32 - 320 Hz

• 70 Watts RMS x 4 @ 4 ohm
• 100 Watts RMS x 4 @ 2 ohm
• Total Peak Power: 1000 Watts
• Variable Bass Boost: 0 to +9 dB
• Heavy duty aluminum alloy heat-sink for extreme heat dissipation
• Frequency Response: 32 - 320 Hz

Infinity Kappa K4 Amplifier with Clari-fi Technology

1500W Peak (480W RMS) High Performance Kappa Series Class-D 4-Channel 2-Ohm Stable Amplifier with Bluetooth and Clari-Fi Technology

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1500W Peak (480W RMS) High Performance Kappa Series Class-D 4-Channel 2-Ohm Stable Amplifier with Bluetooth and Clari-Fi Technology

• 100 Watts RMS x 4 @ 4 ohm
• 120 Watts RMS x 4 @ 2 ohm
• 240 Watts RMS x 2 @ 4 ohm Bridged
• Total Peak Power: 1500 Watts
• Bluetooth Streaming
• Clari-fi Technology
• Wired control panel
• Speaker-level (high-level) inputs

• 100 Watts RMS x 4 @ 4 ohm
• 120 Watts RMS x 4 @ 2 ohm
• 240 Watts RMS x 2 @ 4 ohm Bridged
• Total Peak Power: 1500 Watts
• Bluetooth Streaming
• Clari-fi Technology
• Wired control panel
• Speaker-level (high-level) inputs

Infinity Reference 7541a

4-Channel Amplifier

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4-Channel Amplifier

656 watts max 4-channel amplifier • Optional bass remote • 4 ohm: 278 watts RMS x 2 chan.• RCA and speaker level inputs • Bass boost 0 - 12dB

656 watts max 4-channel amplifier • Optional bass remote • 4 ohm: 278 watts RMS x 2 chan.• RCA and speaker level inputs • Bass boost 0 - 12dB

Infinity KAPPA 4 AMPLIFIER

240W RMS Class-D 4-Channel Car Amplifier

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240W RMS Class-D 4-Channel Car Amplifier

• 100 watts x 4 channel @ 4 ohm
• 120 watts x 4 channel @ 2 ohm
• Bridged: 240 watts x 2 channel @ 4 ohm
• Total RMS Power: 120 watts
• Class D 2 ohm Stable 4-Channel Amplifier

• 100 watts x 4 channel @ 4 ohm
• 120 watts x 4 channel @ 2 ohm
• Bridged: 240 watts x 2 channel @ 4 ohm
• Total RMS Power: 120 watts
• Class D 2 ohm Stable 4-Channel Amplifier

Infinity BassLink 4SC

4-Channel, Multi-Channel Amplifier Expansion Module for Basslink II

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4-Channel, Multi-Channel Amplifier Expansion Module for Basslink II

35W x 4 (at 4 ohm), 50W x 4 (at 2 ohm) power amplifier that slots loads directly into the BassLink II. Coupled with the BassLink II, the 4sc will deliver real power to your front speakers and rear speakers

35W x 4 (at 4 ohm), 50W x 4 (at 2 ohm) power amplifier that slots loads directly into the BassLink II. Coupled with the BassLink II, the 4sc will deliver real power to your front speakers and rear speakers

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148 watts RMS x 2 + 287 watts RMS x 1 in bridged mode • 80 watts RMS x 4 + 150 watts RMS x 2 at 2 ohm • variable high-/low-pass filters • variable Bass EQ • speaker-level inputs

148 watts RMS x 2 + 287 watts RMS x 1 in bridged mode • 80 watts RMS x 4 + 150 watts RMS x 2 at 2 ohm • variable high-/low-pass filters • variable Bass EQ • speaker-level inputs

Infinity Reference 475a

468W Reference Series Class AB 4-Channel Amplifier

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468W Reference Series Class AB 4-Channel Amplifier

• 75W x 4-Chan. @ 4 ohm
• 90W x 4-Chan. @ 2 ohm
• 117W x 4-Chan. Max
• MOSFET power supply
• Gold-plated preamp RCA outputs

• 75W x 4-Chan. @ 4 ohm
• 90W x 4-Chan. @ 2 ohm
• 117W x 4-Chan. Max
• MOSFET power supply
• Gold-plated preamp RCA outputs

Infinity Reference 704A Open Box (Complete)

1000W Peak (400W RMS) Reference Series 4-Channel Amplifier

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1000W Peak (400W RMS) Reference Series 4-Channel Amplifier

• 70 Watts RMS x 4 @ 4 ohm
• 100 Watts RMS x 4 @ 2 ohm
• Total Peak Power: 1000 Watts
• Variable Bass Boost: 0 to +9 dB
• Heavy duty aluminum alloy heat-sink for extreme heat dissipation
• Frequency Response: 32 - 320 Hz

• 70 Watts RMS x 4 @ 4 ohm
• 100 Watts RMS x 4 @ 2 ohm
• Total Peak Power: 1000 Watts
• Variable Bass Boost: 0 to +9 dB
• Heavy duty aluminum alloy heat-sink for extreme heat dissipation
• Frequency Response: 32 - 320 Hz

Infinity Reference 475a R/B

(Factory Refurbished) 468W Max, Reference Series Class AB 4-Channel Amplifier (REF475A)

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(Factory Refurbished) 468W Max, Reference Series Class AB 4-Channel Amplifier (REF475A)

Reference Series Class AB 4-Channel Amplifier • 75W x 4 chan. @ 4 ohm • 90W x 4 chan. @ 2 ohm • 117W x 4 chan. Max • MOSFET power supply • Gold-plated preamp RCA outputs

Reference Series Class AB 4-Channel Amplifier • 75W x 4 chan. @ 4 ohm • 90W x 4 chan. @ 2 ohm • 117W x 4 chan. Max • MOSFET power supply • Gold-plated preamp RCA outputs

Infinity Reference 7541a

Factory Refurbished 4-Channel Amplifier w/ 1-YEAR EXCHANGE WARRANTY (as if it was new!)

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Factory Refurbished 4-Channel Amplifier w/ 1-YEAR EXCHANGE WARRANTY (as if it was new!)

656 watts max 4-channel amplifier • Optional bass remote • 4 ohm: 278 watts RMS x 2 chan.• RCA and speaker level inputs • Bass boost 0 - 12dB

656 watts max 4-channel amplifier • Optional bass remote • 4 ohm: 278 watts RMS x 2 chan.• RCA and speaker level inputs • Bass boost 0 - 12dB

Infinity K4 Amplifier with Clari-fi Technology (Open Box)

1500W Peak (480W RMS) High Performance Kappa Series Class-D 4-Channel 2-Ohm Stable Amplifier with Bluetooth and Clari-Fi Technology

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1500W Peak (480W RMS) High Performance Kappa Series Class-D 4-Channel 2-Ohm Stable Amplifier with Bluetooth and Clari-Fi Technology

• Item Condition: Like New Open Box
• 100 Watts RMS x 4 @ 4 ohm
• 120 Watts RMS x 4 @ 2 ohm
• 240 Watts RMS x 2 @ 4 ohm Bridged
• Total Peak Power: 1500 Watts
• Bluetooth Streaming
• Clari-fi™ Technology
• Wired control panel
• Speaker-level (high-level) inputs

• Item Condition: Like New Open Box
• 100 Watts RMS x 4 @ 4 ohm
• 120 Watts RMS x 4 @ 2 ohm
• 240 Watts RMS x 2 @ 4 ohm Bridged
• Total Peak Power: 1500 Watts
• Bluetooth Streaming
• Clari-fi™ Technology
• Wired control panel
• Speaker-level (high-level) inputs

Infinity Reference 475a Open Box

(Open Box) 468W Max, Reference Series Class AB 4-Channel Amplifier (REF475A)

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(Open Box) 468W Max, Reference Series Class AB 4-Channel Amplifier (REF475A)

Reference Series Class AB 4-Channel Amplifier • 75W x 4 chan. @ 4 ohm • 90W x 4 chan. @ 2 ohm • 117W x 4 chan. Max • MOSFET power supply • Gold-plated preamp RCA outputs

Reference Series Class AB 4-Channel Amplifier • 75W x 4 chan. @ 4 ohm • 90W x 4 chan. @ 2 ohm • 117W x 4 chan. Max • MOSFET power supply • Gold-plated preamp RCA outputs

Infinity Reference 5350a R/B

5-Channel Reference Series Amplifier (REF5350A)

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5-Channel Reference Series Amplifier (REF5350A)

Reference Series Class AB 5-Channel Amplifier • 50W x 4 chan. + 150 watts x 1 chan. @ 4 ohm • 60W x 4 chan. + 300 watts x 1 chan. @ 2 ohm • 89W x 4 chan. Max • MOSFET power supply • Gold-plated preamp RCA outputs

Reference Series Class AB 5-Channel Amplifier • 50W x 4 chan. + 150 watts x 1 chan. @ 4 ohm • 60W x 4 chan. + 300 watts x 1 chan. @ 2 ohm • 89W x 4 chan. Max • MOSFET power supply • Gold-plated preamp RCA outputs

Infinity KAPPA FOUR Open Box

(Open Box) 1200W Max, Kappa Series 4-Channel Amplifier (KAPPA-FOUR)

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(Open Box) 1200W Max, Kappa Series 4-Channel Amplifier (KAPPA-FOUR)

Kappa Series 4-Channel Amplifier • 125W x 4 Chan. @ 4 Ohm • 150W x 4 Chan. @ 2 Ohm • 300W x 4 Chan. Max • Tuned Bass EQ • Speaker-level Inputs • Variable High and Low Pass Filters • 4/3/2 Channel Operation

Kappa Series 4-Channel Amplifier • 125W x 4 Chan. @ 4 Ohm • 150W x 4 Chan. @ 2 Ohm • 300W x 4 Chan. Max • Tuned Bass EQ • Speaker-level Inputs • Variable High and Low Pass Filters • 4/3/2 Channel Operation

Infinity Kappa Four (Like New (Open Box))

1500W Peak (480W RMS) Kappa Series Class-D 4-Channel Amplifier

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1500W Peak (480W RMS) Kappa Series Class-D 4-Channel Amplifier

• 100 watts x 4 channel @ 4 ohm
• 120 watts x 4 channel @ 2 ohm
• Bridged: 240 watts x 2 channel @ 4 ohm
• Total RMS Power: 480 watts
• Class D 2 ohm Stable 4-Channel Amplifier

• 100 watts x 4 channel @ 4 ohm
• 120 watts x 4 channel @ 2 ohm
• Bridged: 240 watts x 2 channel @ 4 ohm
• Total RMS Power: 480 watts
• Class D 2 ohm Stable 4-Channel Amplifier

Infinity KAPPA FOUR

1200W Kappa Series 4-Channel Amplifier

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1200W Kappa Series 4-Channel Amplifier

• 125W x 4-Chan. @ 4 Ohm
• 150W x 4-Chan. @ 2 Ohm
• 300W x 4-Chan. Max
• Tuned Bass EQ
• Speaker-level Inputs
• Variable High and Low Pass Filters
• 4/3/2 Channel Operation

• 125W x 4-Chan. @ 4 Ohm
• 150W x 4-Chan. @ 2 Ohm
• 300W x 4-Chan. Max
• Tuned Bass EQ
• Speaker-level Inputs
• Variable High and Low Pass Filters
• 4/3/2 Channel Operation

Infinity Primus 6004A

560W Peak (280W RMS) Primus Series Class-D 4-Channel Amplifier

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560W Peak (280W RMS) Primus Series Class-D 4-Channel Amplifier

• 60 watts x 4 channel @ 4 ohm
• 70 watts x 4 channel @ 2 ohm
• Bridged: 140 watts x 2 channel @ 4 ohm
• Total RMS Power: 280 watts
• Class D 2 ohm Stable 4-Channel Amplifier

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VIP Product Get $21.00 in rewards to spend later

• 60 watts x 4 channel @ 4 ohm
• 70 watts x 4 channel @ 2 ohm
• Bridged: 140 watts x 2 channel @ 4 ohm
• Total RMS Power: 280 watts
• Class D 2 ohm Stable 4-Channel Amplifier

Infinity Reference 704A

1000W Peak (400W RMS) Reference Series 4-Channel Amplifier

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1000W Peak (400W RMS) Reference Series 4-Channel Amplifier

• 70 Watts RMS x 4 @ 4 ohm
• 100 Watts RMS x 4 @ 2 ohm
• Total Peak Power: 1000 Watts
• Variable Bass Boost: 0 to +9 dB
• Heavy duty aluminum alloy heat-sink for extreme heat dissipation
• Frequency Response: 32 - 320 Hz

• 70 Watts RMS x 4 @ 4 ohm
• 100 Watts RMS x 4 @ 2 ohm
• Total Peak Power: 1000 Watts
• Variable Bass Boost: 0 to +9 dB
• Heavy duty aluminum alloy heat-sink for extreme heat dissipation
• Frequency Response: 32 - 320 Hz

Infinity Kappa Four

1500W Peak (480W RMS) Kappa Series Class-D 4-Channel Amplifier

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1500W Peak (480W RMS) Kappa Series Class-D 4-Channel Amplifier

• 100 watts x 4 channel @ 4 ohm
• 120 watts x 4 channel @ 2 ohm
• Bridged: 240 watts x 2 channel @ 4 ohm
• Total RMS Power: 480 watts
• Class D 2 ohm Stable 4-Channel Amplifier

VIP Star Icon

VIP Product Get $33.00 in rewards to spend later

• 100 watts x 4 channel @ 4 ohm
• 120 watts x 4 channel @ 2 ohm
• Bridged: 240 watts x 2 channel @ 4 ohm
• Total RMS Power: 480 watts
• Class D 2 ohm Stable 4-Channel Amplifier

Infinity Reference 3004A - New (Damaged Packaging, Product A+)

400W RMS Class H Reference Series 4 Channel Car Amplifier

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400W RMS Class H Reference Series 4 Channel Car Amplifier

• 75 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel @ 2 ohm
• Bridged: 200 watts x 2 channel @ 4 ohm
• Total RMS Power: 400 watts
• Class H 2 ohm Stable 4-Channel Amplifier

• 75 watts x 4 channel @ 4 ohm
• 100 watts x 4 channel @ 2 ohm
• Bridged: 200 watts x 2 channel @ 4 ohm
• Total RMS Power: 400 watts
• Class H 2 ohm Stable 4-Channel Amplifier

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    Infinity 4-Channel Amplifiers Information

    A 4 channel car amplifier from Infinity will provide your vehicle with the power it requires. These amps can operate four channels and Infinity is a leader in amplification solutions. Power your speakers with a Infinity 4-channel amplifier for a great all around sound.
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    Take advantage of our VIP rewards like 10% back on your purchases, free 2-day shipping, extended warranties, and free returns! Gain access to all of these rewards without any membership fees.
    Get great discounted (and possibly FREE) installation accessories with most car stereo purchases. This includes dash kits, wiring harnesses and antenna adapters that you will need to properly install your new car stereo.
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    Our trained experts are here to assist you! They are just a phone call or click away to help you get the right gear for you and your vehicle!
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