Ruthless Audio 800.4 4 Channel Amplifier
When your speaker build calls for four powerful channels and flexible tuning, consider the Ruthless Audio 800.4 4-Channel Amplifier. This full-size Korean Class-D model is distinct from the 800.4 Micro: it offers a published 220W x 4 at 2 ohms, bridgeable channels, locking RCA inputs, and a clip light. Use it for front and rear speakers, a component stage, or a properly matched bridged setup.
At 14.4V, the listed ratings are 220W x 4 @ 2 ohms, 100W x 4 @ 4 ohms, and 440W x 2 bridged @ 4 ohms. Tiffany-style locking RCA inputs help keep signal leads seated, while 4 AWG power inputs accept the indicated cable size. The onboard clip light offers a visual clipping warning, though it does not replace proper gain-setting measurements. Input sensitivity is 0.2V–6V and the stated operating range is 8–16V. The published THD figure is less than 0.01% at 4Ω.
The crossover controls support different speaker arrangements: high-pass adjustment from 20Hz–800Hz, or 200Hz–8kHz with the x10 setting; low-pass adjustment from 50Hz–800Hz, or 500Hz–8kHz with x10. That gives you useful options for a speaker stage or a bridged channel pair. The listing recommends a 100A fuse; check the manufacturer's instructions and size the power run and protection for your installation.
Why Choose the Ruthless Audio 800.4 4-Channel Amplifier?
- 220W x 4 @ 2 Ohms — Listed four-channel RMS output at 14.4V for speakers with suitable power handling.
- 440W x 2 Bridged @ 4 Ohms — Two bridged pairs offer another configuration when your drivers and final loads match the rating.
- Korean Class-D Design — The listed amplifier class and construction for this full-size model.
- Tiffany-Style Locking RCA Inputs — Locking RCA connections help keep cables secure.
- 4 AWG Power Inputs — Power terminals sized for 4-gauge cable; plan the full run and grounding accordingly.
- Clip Light Function — A visible signal-clipping indicator to assist with setup and monitoring.
- Crossover Controls with x10 Setting — HPF 20Hz–800Hz or 200Hz–8kHz; LPF 50Hz–800Hz or 500Hz–8kHz.
- THD < 0.01% @ 4Ω — A published distortion specification for the stated load.
Amplifier & Wiring Recommendations
Match the 800.4 to component or coaxial speakers with the right impedance and RMS handling for its actual channel output. Supply a compatible four-channel RCA signal from your head unit or DSP. The listing calls for 4-gauge power and ground wiring and recommends a 100A fuse; confirm cable length, fuse placement, and protection with the manufacturer's guidance. Keep connections secure and route signal cables away from power wiring where practical to help reduce noise.
If bridging, confirm a minimum 4Ω load per bridged pair and speakers or subwoofer suited to the listed 440W output. The clip light is a useful warning while setting gain, but music dynamics and source levels vary. Follow a proper gain-setting procedure, ideally using appropriate test equipment, instead of treating the light going out as a guarantee that the entire system cannot clip. An upstream DSP can add time alignment, EQ, and additional crossover control when your build needs it.
Full Specifications
| Specification | Value |
|---|---|
| RMS Power @ 4Ω (14.4V) | 100W x 4 |
| RMS Power @ 2Ω (14.4V) | 220W x 4 |
| Bridged Power @ 4Ω (14.4V) | 440W x 2 |
| Amplifier Class | Class-D (Korean) |
| Channels | 4 (Bridgeable to 2) |
| High Pass Filter | 20Hz–800Hz / 200Hz–8kHz (x10) |
| Low Pass Filter | 50Hz–800Hz / 500Hz–8kHz (x10) |
| THD | < 0.01% @ 4Ω |
| Input Sensitivity | 0.2V – 6V |
| RCA Inputs | Tiffany-Style Locking RCA |
| Power Input Gauge | 4 AWG |
| Clip Light | Yes |
| Operating Voltage | 8–16V |
| Recommended Fuse | 100A |
| Warranty | 1 Year Standard / 2 Year Extended Available |
Note: Physical dimensions are not included in this listing. Contact us for the full spec sheet before planning a tight installation.
Frequently Asked Questions
Q: What is the difference between the Ruthless Audio 800.4 and the 800.4 Micro?
A: This full-size 800.4 is listed at 220W x 4 into 2Ω and includes locking RCA inputs, 4 AWG power terminals, a clip light, and x10 crossover settings. The compact 800.4 Micro is listed at 200W x 4 into 2Ω with a 9.25" overall length. Compare the detailed specs and available mounting space before choosing.
Q: What wiring kit do I need for the Ruthless Audio 800.4?
A: The listing recommends 4-gauge power and ground cable and a 100A fuse. Confirm the cable sizing and fuse location for your vehicle and installation.
Q: Can I bridge the 800.4 to run a subwoofer?
A: Yes. A bridged pair is rated at 440W into 4Ω at 14.4V. You can reserve another pair for speakers if the rest of your system is configured appropriately; maintain at least the specified bridged impedance.
Q: How do I use the clip light to set my gain?
A: Use it as a clipping warning while following the manufacturer's gain-setting instructions. A DMM or oscilloscope and a suitable test signal can provide a more controlled setup than adjusting gain by ear or by the indicator alone.
