Alliance Audio VL20004 4-Channel Class D Amplifier

The Alliance Audio VL20004 is a compact, high-efficiency 4-channel Class D amplifier delivering 4 × 250 watts RMS at 2 ohms — 2000 watts peak — in a slim chassis measuring just 14.7 cm × 25.9 cm × 4.8 cm. Built for enthusiasts who demand full-range amplification without sacrificing trunk space or install flexibility, the VL20004 powers component speaker sets, coaxial speakers, and mid-bass drivers with clean, high-headroom output across a frequency range of 10Hz to 40kHz. Its Full Range Class D topology runs at 82% efficiency, keeping heat low and power delivery consistent even during extended high-volume listening.

The VL20004 features independent high-pass and low-pass filters (50Hz–250Hz) on each channel pair, giving you precise crossover control for a properly staged soundstage without an external processor. A wide input sensitivity range of 0.2V–6V ensures seamless integration with factory head units, aftermarket decks, and DSP outputs. With a damping factor of 100, the amp delivers tight, controlled output to your speakers for accurate midrange and high-frequency reproduction. The 9V–16V operating range makes it compatible with virtually any 12V vehicle electrical system, and the compact 4.8 cm mounting depth opens up under-seat and under-dash install locations that full-size 4-channel amps simply can't reach.

At Trinity Car Audio, the Alliance Audio VL20004 is an ideal choice for building a full front stage — pair it with a quality set of component speakers up front and coaxials in the rear, or bridge channels 3 and 4 to drive a mid-bass subwoofer while channels 1 and 2 handle your tweeters and mids. Whether you're upgrading a factory system or building a clean, space-efficient custom install, the VL20004 delivers the power, precision, and compact footprint to get it done right.

Why Choose the Alliance Audio VL20004?

• 4 × 250W RMS at 2 Ohms: Real-world power across all four channels for crisp, dynamic full-range sound reproduction.
• Ultra-Compact Class D Design: At just 14.7 × 25.9 × 4.8 cm, it fits under seats, behind panels, and in tight trunk corners where standard 4-channel amps won't go.
• 82% Efficiency Rating: Full Range Class D topology runs significantly cooler than Class A/B, reducing heat buildup and extending amp longevity.
• 10Hz–40kHz Frequency Response: Full-range output from deep sub-bass extension to crystal-clear high-frequency detail.
• Built-In High & Low Pass Filters (50–250Hz): Dial in your crossover points on each channel pair without an external processor or DSP.
• Wide Input Sensitivity (0.2V–6V): Plug directly into factory head units or aftermarket decks without a line output converter in most applications.
• Bridgeable Channels: Bridge channels 3 & 4 to power a mid-bass driver or small subwoofer while channels 1 & 2 handle your front stage.
• Damping Factor of 100: Delivers controlled, accurate speaker movement for tight midrange and clean high-frequency output.

Speaker Pairing & Wiring Recommendations

The VL20004 is best matched with component speakers or coaxials rated between 75–250W RMS per channel. For a front stage build, run channels 1 and 2 to a set of 6.5" component speakers (tweeters and woofers) and channels 3 and 4 to rear coaxials or a second set of components. To bridge channels 3 and 4 for a mono mid-bass output, ensure the bridged load is no lower than 4 ohms. Wire the amp with a minimum 4-gauge power and ground cable, fused within 18 inches of the battery. Set the high-pass filter between 80–100Hz to keep low-frequency content out of your speakers and protect them from over-excursion.

Full Specifications

Frequently Asked Questions

Can I use the VL20004 with a factory head unit?
Yes. The 0.2V–6V input sensitivity range makes it compatible with low-voltage factory outputs in most vehicles. No line output converter is required in the majority of OEM applications.

Can I bridge the VL20004 for more power?
Yes — channels 3 and 4 (and channels 1 and 2) can be bridged for higher mono output. When bridging, ensure the speaker load is no lower than 4 ohms to keep the amp stable and within its thermal limits.

What speakers work best with this amp?
Component speaker sets or coaxials rated 75–250W RMS per channel are ideal. 6.5" or 6×9" speakers in the 4-ohm range will give you the best balance of power and efficiency from the VL20004.

What power wire gauge do I need?
Use a minimum 4-gauge power and ground cable. With a max current draw of 80A, install an 80A inline fuse within 18 inches of the battery for safe, reliable operation.