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Home/Equipment/Amplifiers/Sundown Audio/Stereo Integrity SIQ 75.4 High-Fidelity 4-Channel Amplifier
Sundown Audio SIQ 75.4 Amplifier - 120W RMS per channel, 4-Channel Class AB, 2-Ohm Stable, Non-Bridgeable - Black aluminum chassis with visible internal components, RCA inputs, and speaker terminals.
Sundown Audio/Amplifier

Stereo Integrity SIQ 75.4 High-Fidelity 4-Channel Amplifier

Stereo Integrity SIQ 75.4 Amplifier: Purity at its Finest for Your Soundstage The Stereo Integrity SIQ 75.4 signals the return of true high-fidelity audio engineering to the mobile sound space. Built by audiophiles for the most discerning listeners, this 4-Channel Class A/B amplifier prioritizes signal integrity above all else. Its core design features zero filters, zero crossovers, and zero EQ , delivering a full bandwidth signal (5 Hz to 150,000 Hz) that is clean, precise, and uncompromised. This is the foundation for an accurate soundstage and breathtaking sonic detail. Uncompromised Audiophile Construction Every component in the SIQ 75.4 was selected for its acoustic performance and durability: Output Transistors: Utilizes audiophile-grade TO-3 output transistors for clean, linear power. Internal Circuitry: Features high-quality UPC4570 op-amps , IRFPO64N power supply transistors , and sand cast resistors throughout. Connections: Equipped with premium Tiffany-style RCA connections accepting inputs up to 16 Volts. Chassis: Protected by a thick extruded aluminum chassis with a copper anodized shielded transformer cover to minimize electromagnetic interference, all visible through a large plexiglass viewing window . Clean Power, Ultra-Low Distortion Performance The SIQ 75.4 delivers precise power with unmatched fidelity, validated by Audio Precision measurements : Rated RMS Power Output (4 Channels): 75W RMS x4 @ 4Ω High Current Output: 120W RMS x4 @ 2Ω Bridged Power: 120W RMS x2 @ 4Ω Total Harmonic Distortion (THD): An ultra-low 0.03 % Signal-to-Noise Ratio (SNR): 90 dB Installation and Specifications Purity Control: Features a discrete gain knob per channel for precise level matching. Dimensions: Compact size at 14 x 8 x 2 Inches . Current Draw: Maximum current draw of 66 amps. The SIQ 75.4 is the ideal solution for audiophiles seeking true sound reproduction for their front and rear stage speakers. Amplifiers Specifications Frequency Response Minimum 5 Hz Frequency Response Maximum 150,000 Hz Signal-to-Noise Ratio (SNR) 90 dB Total Harmonic Distortion (THD) 0.03 % Dimensions (W x H x D) 14 x 8 x 2 Inches Rated RMS power output into all 4 channels at 4 ohm 75 Watts Rated RMS power output into all 4 channels at 2 ohm 120 Watts Bridged RMS power into 2 channels at 4 ohm 120 Watts Power Idle Current Draw 1.2 amps Maximum Current Draw 66 amps Connections RCA Input Maximum 16 Volts
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Specifications

class
AB
channels
4
rms watts
120 W
Compare Prices(1 retailer)
Sparked Innovations
Sparked InnovationsBest Price
Available
$189.99
Updated 3/24/2026
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Frequently Asked Questions

What is the Sundown Audio Stereo Integrity SIQ 75.4 High-Fidelity 4-Channel Amplifier?

The Sundown Audio Stereo Integrity SIQ 75.4 High-Fidelity 4-Channel Amplifier is a car audio equipment made by Sundown Audio. View full specifications and where to buy on this page.

How much does the Sundown Audio Stereo Integrity SIQ 75.4 High-Fidelity 4-Channel Amplifier cost?

The Sundown Audio Stereo Integrity SIQ 75.4 High-Fidelity 4-Channel Amplifier typically sells for $303 to $379 depending on the retailer and variant. Check the "Where to Buy" section for current pricing from authorized dealers.

Where can I buy the Sundown Audio Stereo Integrity SIQ 75.4 High-Fidelity 4-Channel Amplifier?

You can purchase the Sundown Audio Stereo Integrity SIQ 75.4 High-Fidelity 4-Channel Amplifier from authorized dealers listed in the "Where to Buy" section on this page. We recommend buying from authorized retailers to ensure warranty coverage and genuine products.

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