Soundqubed HDX4.2 Series 15" Subwoofer 4" DVC 4,000 Watts RMS D2/D4
Soundqubed HDX4.2 Series 15" Subwoofer 4" DVC 4,000 Watts RMS D2/D4 - Dual 2 Ohm is backordered and will ship as soon as it is back in stock.
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Soundqubed HDX4.2 Series 15" Subwoofer 4" DVC 4,000 Watts...
Description
Description
SoundQubed HDX4.2-15 — 4,000W RMS Competition-Grade 15" Subwoofer
The SoundQubed HDX4.2 Series 15" subwoofer is a professional-grade, high-output 15-inch driver built for SPL competitors and serious builders who demand maximum cone area, infrasonic bass extension, and uncompromising thermal endurance. Rated at 4,000 watts RMS and 8,000 watts peak, the HDX4.2-15 is powered by a 402 oz magnet, a 4-inch diameter voice coil with a 70mm coil length, and a motor assembly engineered for extreme linear excursion. Available in Dual 2 Ohm (D2) and Dual 4 Ohm (D4) configurations, this sub wires cleanly into virtually any high-power mono block amplifier setup.
With an Xmax of 23mm (±) and Xmech of 47mm (±), the HDX4.2-15 delivers massive linear cone travel across its 805 cm² cone area (SD), producing authoritative sub-bass extension down to a free-air resonance (Fs) of 33.7 Hz (D2) / 33.9 Hz (D4). With sensitivity ratings of 88.3–88.5 dB, this is a highly efficient driver that gets devastatingly loud even on moderate amplifier power — and absolutely punishing when fed its full 4,000W RMS rating.
Why Choose the SoundQubed HDX4.2-15?
- 4,000W RMS / 8,000W Peak Power: Handles extreme amplifier output without flinching — built for high-power mono block amplifiers in daily and competition installs.
- 402 oz Magnet Assembly: Massive motor force delivers exceptional BL (17.1 N/A D2 / 22.8 N/A D4) for precise, controlled cone movement at high excursion levels.
- 4" Voice Coil, 70mm Coil Length: Extended coil length maximizes gap interaction for superior thermal management and sustained high-power performance.
- 23mm Xmax / 47mm Xmech: Exceptional linear and mechanical excursion — deep, authoritative bass without bottoming out.
- Dual 2 Ohm & Dual 4 Ohm Available: Wire D2 to 1Ω or 4Ω, wire D4 to 2Ω or 8Ω — maximum flexibility for any amplifier's stable impedance load.
- Fs of 33.7–33.9 Hz: Tuned for deep sub-bass reproduction — ideal for ported enclosures targeting 30–36 Hz tuning frequencies.
- Ported Enclosure Optimized: Recommended ported volume 3–6 ft³ and sealed 1.88–3.5 ft³ — versatile for any build style.
- 88.3–88.5 dB Sensitivity: Highly efficient — gets seriously loud without demanding every last watt from your amplifier.
Amplifier & Enclosure Recommendations
The HDX4.2-15 is designed to be paired with a high-output mono block amplifier capable of delivering 4,000W RMS or more at the wired impedance load. For the D2 (Dual 2 Ohm) variant, wire the coils in parallel for a 1Ω final load or in series for 4Ω. For the D4 (Dual 4 Ohm) variant, wire in parallel for 2Ω or in series for 8Ω. Most high-power Class D mono amps are stable at 1Ω, making the D2 the most common choice for single-sub builds.
For enclosures, a ported box tuned to 30–36 Hz in the 3–6 ft³ range will maximize SPL output and low-frequency extension. For tighter, more accurate SQL bass, a sealed box in the 1.88–3.5 ft³ range provides excellent transient response and cone control.
Electro Acoustic Specifications & Thiele Small Parameters
| Specification | HDX4.2-15D2 | HDX4.2-15D4 |
|---|---|---|
| Woofer Size | 15" | 15" |
| RMS Power | 4,000 W | 4,000 W |
| Peak Power | 8,000 W | 8,000 W |
| Magnet Weight | 402 oz | 402 oz |
| Coil Diameter | 4 in | 4 in |
| Coil Length | 70 mm | 70 mm |
| Fs | 33.7 Hz | 33.9 Hz |
| Impedance | 2+2 Ohm | 4+4 Ohm |
| QMS | 3.57 | 3.56 |
| QES | 0.49 | 0.51 |
| QTS | 0.43 | 0.45 |
| VAS | 57.2 L | 56.6 L |
| Le | 1.03 mH | 1.67 mH |
| η (No) | 0.43% | 0.40% |
| CMS | 0.06 mm/N | 0.06 mm/N |
| Sensitivity (1W/1M) | 88.3 dB | 88.5 dB |
| BL | 17.1 N/A | 22.8 N/A |
| Xmax (±) | 23 mm | 23 mm |
| Xmech (±) | 47 mm | 47 mm |
| SD | 805 cm² | 805 cm² |
Mounting Dimensions
| Model | A | B | C | D |
|---|---|---|---|---|
| HDX4.2-15D2 | 390 mm / 15.4" | 350 mm / 13.78" | 260 mm / 10.24" | 243 mm / 9.57" |
| HDX4.2-15D4 | 390 mm / 15.4" | 350 mm / 13.78" | 260 mm / 10.24" | 243 mm / 9.57" |
Enclosure Suggestions
| Enclosure Type | HDX4.2-15 D2/D4 |
|---|---|
| Sealed Enclosure | 1.88–3.5 ft³ |
| Ported Enclosure | 3–6 ft³ |
Frequently Asked Questions
What amplifier do I need for the SoundQubed HDX4.2-15?
You need a mono block amplifier rated at 4,000W RMS or more at your wired impedance. The D2 wired to 1Ω is the most common pairing. Look for a high-current Class D mono amp stable at 1Ω for best results.
Should I choose the D2 or D4 version?
Choose D2 (Dual 2 Ohm) if your amplifier is stable at 1Ω (parallel) or 4Ω (series) — this is the most common configuration. Choose D4 (Dual 4 Ohm) if your amp is stable at 2Ω (parallel) or you need an 8Ω final load (series).
What size box does the HDX4.2-15 need?
For ported, use 3–6 ft³ tuned to approximately 30–36 Hz for maximum SPL and deep bass extension. For sealed, use 1.88–3.5 ft³ for tight, accurate bass.
Can this subwoofer handle daily use or is it competition-only?
The HDX4.2-15 is built for both. Its 88.3–88.5 dB sensitivity means it gets devastatingly loud efficiently, while its 4,000W RMS rating and 402 oz motor make it a serious SPL and SQL competition contender.
