Stetsom Bravo HQ 400.4 Multichannel Car Audio Digital Amplifier - 2 Ohms Stable 4 Channel

The Stetsom Bravo HQ400.4 is a 4-channel, 2 Ω-stable digital car amplifier delivering 400 W RMS total, built for enthusiasts who want flexible multi-channel power with bridged capability in a compact chassis.

• Number of Channels: 4 — Provides four outputs for a full front/rear speaker setup and keeps options open for independent channels or pairing two outputs in bridge mode for higher power into a single load.
• RMS Power: 400 W total — Indicates continuous, real-world output ability across all channels when operated within its stated specifications.
• RMS Power at 4 Ohm (14.4V): 4 x 60 W RMS — Each channel can deliver up to 60 W into a 4 Ω load with a 14.4 V supply, useful for standard full-range speaker pairs.
• RMS Power at 2 Ohm (14.4V): 4 x 105 W RMS — Higher current capability allows better performance with lower-impedance loads, increasing headroom for demanding speakers.
• RMS Power at 4 Ohm (12.6V): 4 x 50 W RMS — At lower vehicle voltage, power per channel is reduced in 4 Ω loads, affecting perceived loudness but preserving thermal stability.
• RMS Power at 2 Ohm (12.6V): 4 x 85 W RMS — Maintains higher output into 2 Ω loads even at lower nominal voltage, aiding bass and dynamic response.
• Bridge Power (4 Ohms): 2 x 150 W RMS (12.6V) / 2 x 180 W RMS (14.4V) — Bridge mode combines two channels for greater single-load power, ideal for a sub or high-power pair.
• Supply Voltage: 9 V ~ 15.5 V DC — Accepts a broad vehicle electrical range, maintaining performance across different alternator and battery conditions.
• Frequency Response: 5 Hz ~ 30 kHz — Wide bandwidth supports deep bass, clear mids, and crisp highs for a full-range output.
• Crossover (Low Pass / High Pass): 50 Hz ~ 2.3 kHz (Variable) for both — Independent, adjustable filtering to shape the amp’s output and minimize overlap between channels.
• Signal to Noise: > 90 dB — Low noise floor helps preserve detail and reduces hiss in the signal path.
• Input Sensitivity: RCA 200 mV ~ 8.0 V / HIGH 1.5 V — Flexible input level options to accommodate both line-level sources and factory/high-level signals.
• Input Impedance: RCA 15 kΩ / HIGH 1 kΩ — Distinct input impedances support compatibility with varying source devices and wiring schemes.
• Impedance Output: 2 Ω (Stereo) — Stable into 2 Ω loads, providing solid power delivery to low-impedance speakers in stereo configuration.
• Power Consumption (with signal): Music 17 A / Bass 34 A — Indicates current draw under typical listening and bass-heavy conditions, relevant for electrical system planning.
• Dimensions: 58.5 × 127 × 167 mm — Compact footprint suitable for tight installation spaces.
• Weight: 640 g — Lightweight chassis aids handling and installation flexibility.

In a real build, HQ400.4 supports a four-channel front/rear setup with the option to bridge two channels for higher power into a single load. Its 2 Ω stability and generous current capabilities empower engaging bass and clear multi‑channel performance, while the adjustable crossovers and broad input compatibility help tailor the sound to any vehicle environment. The combination of wide frequency response, solid SNR, and compact dimensions makes it a versatile choice for premium installations seeking flexible channel distribution without compromising space or reliability.