Short answer: the Monoprice SW-15. It ranks #14 of 212 subwoofers by sound quality (rated 4.1/5) at $499.99 and is still sold new; the MartinLogan Dynamo 1500X ranks #38 (rated 3.9/5) and is discontinued, so it is only an option used.
What the Monoprice SW-15 does well: A big 15 inch subwoofer with powerful, punchy bass at a budget price, great for movies in a large room. The tradeoff: Budget-tier design, ported room gain dependency, 66.1 lbs (30 kg) mid-size, and limited dynamic headroom.
What the MartinLogan Dynamo 1500X does well: A sealed 15 inch subwoofer with forceful, clean low bass that can fire forward or down, with room correction for several seats. Watch for: Output drops to 100.4dB at 20Hz and 92.9dB at 12.5Hz, which is typical of a sealed design and leaves less room for the deepest effects than a ported 15 inch.
Buy the Monoprice SW-15. It is rated higher for sound quality and still sold new, while the MartinLogan Dynamo 1500X is discontinued.
Looking for alternatives? See the complete Subwoofers rankings.
A big 15 inch subwoofer with powerful, punchy bass at a budget price, great for movies in a large room.
A sealed 15 inch subwoofer with forceful, clean low bass that can fire forward or down, with room correction for several seats.
Prices on this page were last checked October 29, 2026 at 4:42 PM 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
| Monoprice SW-15 | MartinLogan Dynamo 1500X | |
|---|---|---|
| Price | $499.99 | $1,299 Discontinued |
| Ranked | #14 of 212 in Medium Home Subwoofers (30-75 lbs) | #38 of 212 in Medium Home Subwoofers (30-75 lbs) |
| Enclosure | ported, bottom | sealed |
| Output SPL at 15 Hz | 90.0 dB | 95.6 dB |
| Output SPL at 20 Hz | 101.2 dB | 100.4 dB |
| Output SPL at 25 Hz | 106.3 dB | 104.4 dB |
| Output SPL at 31.5 Hz | 111.2 dB | 108.3 dB |
| Output SPL at 40 Hz | 116.0 dB | 113.0 dB |
| Output SPL at 50 Hz | 120.2 dB | 117.1 dB |
| Output SPL at 63 Hz | 120.5 dB | 118.3 dB |
| Output SPL at 80 Hz | 119.5 dB | 117.4 dB |
| CEA-2010-A Average (40-80Hz) | 119.0 dB | 116.5 dB |
| Dimensions | 18.1”H x 21”W x 22.7”D (459.7 x 533.4 x 576.6 mm) | 18.3”H x 16.7”W x 17.6”D (464.8 x 425.4 x 447.0 mm) |
| Weight | 66.1 lbs (30.0 kg) | 52 lbs (23.6 kg) |
| Warranty | 1 | 3 |
| Cabinet Color | black | - |
| Country | United States | United States |
| Measurement Source | Audioholics | Audioholics |
| Frequency Response | 30-150Hz (-10dB) | 20Hz+ (with room correction) |
| Amplifier Power | 600W RMS / 800W peak | 650W RMS / 1300W peak |
| Crossover Frequency | 40-150Hz, 18dB/octave | - |
| Phase Control | 0° or 180° | - |
| Inputs | Stereo line level and speaker level | XLR (LFE), RCA (LFE), RCA (stereo), speaker-level |
| Drivers | 15” (381mm) driver | 15” (381mm) driver |
| Output SPL at 12.5 Hz | - | 92.9 dB |
| Output SPL at 100 Hz | - | 116.2 dB |
| Output SPL at 125 Hz | - | 115.1 dB |
| XLR Input | - | Yes |
| RCA Input | - | Yes |
| TRS Input | - | No |
| Optical Input | - | No |
| Coaxial Input | - | No |
| USB Input | - | No |
| HDMI Input | - | No |
| AES Input | - | No |
| Aux Input | - | No |
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