Short answer: the REL Acoustics HT/1510 Predator II, if you are buying new. The Outlaw Audio Ultra-X13 measures as well as it (#97 vs #98 of 143 subwoofers, 4.1/5 vs 4.1/5) but is discontinued, so only consider it used; the REL Acoustics HT/1510 Predator II is still sold new at $1,799.
The case for the REL Acoustics HT/1510 Predator II: A sealed 15 inch home theater subwoofer with strong, punchy upper bass for movie effects and music. The tradeoff: Deep-bass output is more limited than the strong 40-80 Hz result suggests, so it is not the right choice when the lowest movie effects are the priority.
The case for the Outlaw Audio Ultra-X13: A down ported 13 inch subwoofer with impressive deep bass for its size, now discontinued but worth buying used. The catch: The 635.0H x 457.2W x 584.2D mm cabinet and 104.9 lbs (47.6 kg) mass make this a serious placement and moving commitment.
Buy the REL Acoustics HT/1510 Predator II if you want one new; the Outlaw Audio Ultra-X13 is discontinued, so only look for it used.
Looking for alternatives? See the complete Subwoofers rankings.
A sealed 15 inch home theater subwoofer with strong, punchy upper bass for movie effects and music.
A down ported 13 inch subwoofer with impressive deep bass for its size, now discontinued but worth buying used.
Prices on this page were last checked October 23, 2026 at 8:27 AM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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Specifications Side By Side
| REL Acoustics HT/1510 Predator II | Outlaw Audio Ultra-X13 | |
|---|---|---|
| Price | $1,799.00 | $1,299 Discontinued |
| Ranked | #98 of 143 in Large Home Subwoofers (Over 75 lbs) | #97 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | ported, bottom |
| Output SPL at 15 Hz | 91.4 dB | 101.1 dB |
| Output SPL at 20 Hz | 98.0 dB | 109.8 dB |
| Output SPL at 25 Hz | 104.4 dB | 114.1 dB |
| Output SPL at 31.5 Hz | 111.1 dB | 117.1 dB |
| Output SPL at 40 Hz | 116.9 dB | 118.2 dB |
| Output SPL at 50 Hz | 118.5 dB | 118.0 dB |
| Output SPL at 63 Hz | 118.5 dB | 118.1 dB |
| Output SPL at 80 Hz | 118.4 dB | 118.1 dB |
| Output SPL at 100 Hz | 118.5 dB | 118.0 dB |
| Output SPL at 125 Hz | 118.0 dB | 117.6 dB |
| CEA-2010-A Average (40-80Hz) | 118.1 dB | 118.1 dB |
| Dimensions | 18”H x 21.3”W x 19.4”D (457.2 x 541.0 x 492.8 mm) | 25”H x 18”W x 23”D (635.0 x 457.2 x 584.2 mm) |
| Weight | 99.6 lbs (45.2 kg) | 104.9 lbs (47.6 kg) |
| Warranty | 3 | 3 |
| Cabinet Color | black | - |
| Country | United Kingdom | United States |
| Measurement Source | Audioholics | Audioholics |
| Drivers | 15” (381mm) driver | 13” (330mm) driver |
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