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Home/Equipment/Amplifiers/Sundown Audio/Stereo Integrity SIQ 125.4 High-Fidelity 4-Channel Amplifier
Sundown Audio SIQ 125.4 Amplifier - 200W RMS per channel, 4-Channel Class AB, 2-Ohm Stable, Non-Bridgeable - Black aluminum chassis with visible internal components, RCA inputs, speaker terminals.
Sundown Audio/Amplifier

Stereo Integrity SIQ 125.4 High-Fidelity 4-Channel Amplifier

Stereo Integrity SIQ 125.4 Amplifier: Purity at its Finest The Stereo Integrity SIQ 125.4 signals the return of true high-fidelity audio engineering to the mobile sound space. Built by audiophiles for audiophiles, this Class A/B amplifier prioritizes signal integrity above all else. Its design features zero filters, zero crossovers, and zero EQ , delivering a full bandwidth signal (5 Hz to 150, 000 Hz) that is uncompromisingly pure. This is the foundation for an accurate soundstage and breathtaking sonic detail. Uncompromised Audiophile Construction Every component in the SIQ 125. 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 UPC4570 op-amps , IRFPO64N power supply transistors , and sand cast resistors. Connections: Equipped with premium Tiffany-style RCA connections accepting inputs up to 16 Volts. Chassis: Features a thick extruded aluminum chassis with a copper anodized shielded transformer cover to minimize noise, topped with a large plexiglass viewing window . High Power, Ultra-Low Distortion Performance The SIQ 125. 4 delivers robust power with unmatched fidelity, validated by Audio Precision measurements : Rated RMS Power Output (4 Channels): 125W RMS x4 @ 4Ω Rated RMS Power Output (2 Channels): 200W RMS x4 @ 2Ω Bridged Power: 400W RMS x2 @ 4Ω Total Harmonic Distortion (THD): 0.01 % (Exceptional clarity) Signal-to-Noise Ratio (SNR): 91 dB Installation and Specifications Purity Control: Features a discrete gain knob per channel for precise level matching. Dimensions: Compact size at 16.5 x 8 x 2 Inches . Current Draw: Maximum current draw of 98 amps, requiring proper wiring and fusing. The SIQ 125. 4 is the ultimate solution for audiophiles seeking true sound reproduction in their vehicle. Amplifiers Specifications Frequency Response Minimum 5 Hz Frequency Response Maximum 150,000 Hz Signal-to-Noise Ratio (SNR) 91 dB Total Harmonic Distortion (THD) 0.01 % Dimensions (W x H x D) 16.5 x 8 x 2 Inches Rated RMS power output into all 4 channels at 4 ohm 125 Watts Rated RMS power output into all 4 channels at 2 ohm 200 Watts Bridged RMS power into 2 channels at 4 ohm 400 Watts Power Idle Current Draw 1.6 amps Maximum Current Draw 98 amps Connections RCA Input Maximum 16 Volts
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Specifications

class
AB
channels
4
rms watts
200 W
Compare Prices(1 retailer)
Sparked Innovations
Sparked InnovationsBest Price
Available
$224.99
Updated 3/24/2026
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Frequently Asked Questions

What is the Sundown Audio Stereo Integrity SIQ 125.4 High-Fidelity 4-Channel Amplifier?

The Sundown Audio Stereo Integrity SIQ 125.4 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 125.4 High-Fidelity 4-Channel Amplifier cost?

The Sundown Audio Stereo Integrity SIQ 125.4 High-Fidelity 4-Channel Amplifier typically sells for $319 to $399 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 125.4 High-Fidelity 4-Channel Amplifier?

You can purchase the Sundown Audio Stereo Integrity SIQ 125.4 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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