Ruthless Audio 1500.4 4 Channel Amplifier

The Ruthless Audio 1500.4 4-Channel Amplifier is the high-output flagship of the Ruthless Audio 4-channel lineup — a full-power Class-D powerhouse engineered for enthusiasts who demand serious authority across every channel of their system. Putting down 450W x 4 @ 2 ohms and a massive 900W x 2 bridged @ 4 ohms, the 1500.4 has the muscle to drive the most demanding component speakers, pro-audio midranges, and high-power coaxial drivers with authority and headroom to spare. Whether you're building a high-output full-range stage, bridging into a 2-channel configuration for subwoofer duty, or running a competition-level front stage, the 1500.4 delivers the power and precision your build demands.

The 1500.4 steps up the hardware significantly from the 800.4 — featuring 1/0-gauge power inputs and a 200-amp fuse to support its elevated current demands, alongside premium Tiffany-style locking RCA inputs for a clean, reliable signal path at any power level. The onboard clip light function gives you real-time visual clipping indication for accurate gain setup without an oscilloscope, while input sensitivity spanning 0.2V–6V ensures compatibility with any head unit or DSP output. THD of less than 0.01% at 4 ohms confirms the 1500.4 stays clean and accurate even at full output, and the wide 8–16V operating voltage range handles everything from stock to upgraded electrical systems without issue.

The onboard crossover section offers the same wide-range flexibility as the rest of the Ruthless Audio lineup: the high-pass filter sweeps from 20Hz–800Hz (with a x10 multiplier extending to 200Hz–8kHz), and the low-pass filter sweeps from 50Hz–800Hz (x10 to 500Hz–8kHz) — giving you surgical crossover control for both full-range speaker and subwoofer integration without external processors. Bridge channels 1+2 and 3+4 for a 2-channel configuration delivering 900W per side — enough to drive a pair of high-power component midranges or a compact subwoofer alongside your front stage.

Why Choose the Ruthless Audio 1500.4 4-Channel Amplifier?

• 450W x 4 @ 2 Ohms — Flagship 4-channel output that drives the most demanding component speakers and pro-audio drivers with authority and serious headroom.
• 900W x 2 Bridged @ 4 Ohms — Bridge channels in pairs for 900W per side — enough to power high-power component midranges or a compact subwoofer alongside your full speaker stage.
• 1/0-Gauge Power Inputs — Full-size 1/0 AWG terminals minimize resistance and support the 1500.4's elevated current demands for clean, stable power delivery at full output.
• 200-Amp Fuse Rating — Heavy-duty fusing protects your vehicle's electrical system and supports sustained high-output operation without nuisance blows.
• Tiffany-Style Locking RCA Inputs — Premium locking connectors eliminate signal loss and intermittent contact for a clean, reliable signal path at any power level.
• Clip Light Function — Real-time visual clipping indicator lets you dial in your gain structure accurately and protect your speakers from distortion damage without needing an oscilloscope.
• Wide Crossover Range with x10 Multiplier — HPF (20Hz–8kHz) and LPF (50Hz–8kHz) with x10 multiplier give you surgical crossover control for both speaker and subwoofer integration.
• THD < 0.01% @ 4Ω — Exceptionally low total harmonic distortion confirms clean, accurate power delivery even at the 1500.4's elevated output levels.

Amplifier & Wiring Recommendations

The Ruthless Audio 1500.4 is built for high-end component speakers and pro-audio drivers rated in the 200–450W RMS range per channel. Pair it with a quality 4-channel RCA signal from your head unit or DSP processor for best results. A 1/0-gauge power and ground wiring kit with a 200-amp inline fuse is required to properly support the amp's current demands. Keep power and ground runs as short as possible, and route RCA cables away from power wiring to eliminate noise.

When bridging the 1500.4 to 2 channels, verify your speakers or subwoofer can handle the increased output and are rated for a minimum 4-ohm bridged load. Use the onboard clip light to set your gain — back off the gain until the clip light extinguishes at your typical listening volume, then fine-tune from there. For maximum tuning precision, pair the 1500.4 with a DSP processor upstream to handle time alignment, EQ, and crossover duties before the signal reaches the amp.

Full Specifications

Note: Physical dimensions not provided by manufacturer. Contact us for full spec sheet.

Frequently Asked Questions

Q: What is the difference between the Ruthless Audio 1500.4 and the 800.4?
A: The 1500.4 nearly doubles the per-channel output of the 800.4 — 450W x 4 vs. 220W x 4 @ 2 ohms — and steps up to 1/0-gauge power inputs and a 200-amp fuse to match its elevated current demands. Choose the 1500.4 when you need maximum headroom for high-end component speakers, pro-audio drivers, or a high-output full-range stage.

Q: What wiring kit do I need for the Ruthless Audio 1500.4?
A: A 1/0-gauge power and ground wiring kit with a 200-amp inline fuse is required. Do not use 4-gauge wiring — the 1500.4's current demands require 1/0 AWG for clean, stable power delivery at full output.

Q: Can I bridge the 1500.4 to run a subwoofer?
A: Yes — bridge channels 3+4 for 900W @ 4 ohms to power a high-output subwoofer, while channels 1+2 continue to drive your front speakers in stereo. Ensure your subwoofer is rated for a minimum 4-ohm bridged load before wiring.

Q: How do I use the clip light to set my gain?
A: Play music at your typical maximum listening volume, then slowly increase the gain until the clip light illuminates. Back the gain off slightly until the light extinguishes — that's your optimal gain setting. For more precision, use a DMM or oscilloscope alongside the clip light indicator.