Short answer: both are discontinued, so this only matters if you are buying used. Used, the Reaction Audio PV-15X is the better pick: it ranks #22 of 143 subwoofers by sound quality (rated 4.4/5), against #88 (rated 4.1/5) for the Monoprice Monolith M15-S.
Buy the Reaction Audio PV-15X only if you find one used in good condition; both are discontinued, and it is the better rated of the two.
Still deciding? The full Subwoofers rankings cover every ranked option.
Prices on this page were last checked November 7, 2026 at 7:34 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 Monolith M15-S | Reaction Audio PV-15X | |
|---|---|---|
| Price | $999 Discontinued | $1,999 Passive, Discontinued |
| Ranked | #88 of 143 in Large Home Subwoofers (Over 75 lbs) | #22 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | ported, rear |
| Output SPL at 15 Hz | 100.1 dB | 105.3 dB |
| Output SPL at 20 Hz | 105.6 dB | 111.3 dB |
| Output SPL at 25 Hz | 111.2 dB | 116.1 dB |
| Output SPL at 31.5 Hz | 115.2 dB | 119.8 dB |
| Output SPL at 40 Hz | 118.4 dB | 125.3 dB |
| Output SPL at 50 Hz | 119.3 dB | 126.8 dB |
| Output SPL at 63 Hz | 119.6 dB | 126.1 dB |
| Output SPL at 80 Hz | 118.9 dB | 126.5 dB |
| Output SPL at 100 Hz | 119.1 dB | 126.4 dB |
| Output SPL at 125 Hz | 118.9 dB | 126.1 dB |
| CEA-2010-A Average (40-80Hz) | 119.0 dB | 126.2 dB |
| Dimensions | 23.5”H x 16.7”W x 19.7”D (596.9 x 424.2 x 500.4 mm) | 18”H x 22”W x 29”D (457.2 x 558.8 x 736.6 mm) |
| Warranty | 5 | - |
| Country | United States | - |
| Measurement Source | Manufacturer | Data-bass |
| Weight | 80 lbs (36.3 kg) | 149.9 lbs (68 kg) |
| Drivers | 15” (381mm) driver | 15” (381mm) driver |
| Passive | - | Yes |
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