Short answer: the Monoprice SW-15. It ranks #13 of 145 subwoofers by sound quality at $374.99; the XTZ Sound 99 W12S ranks #47 and costs $1499, which makes this an easy call rather than a real tradeoff.
What the Monoprice SW-15 offers: 15-inch ported with 600W RMS (800W peak) delivers Large-room Bassaholic rating. Unrivaled mid-bass punch for $375. Strong output with clean control. Dual speaker-level inputs and 40-150Hz crossover for flexible hookup. Watch for: Budget-tier design, ported room gain dependency, 30 kg mid-size, and limited dynamic headroom.
What the XTZ Sound 99 W12S offers: 12-inch ported with Bang & Olufsen ICEpower half-kilowatt amplification. Sweepable phase knob with flexible EQ1/EQ2 switches for refined tuning. Excellent value high-output performance with powerful, clean amplification. Watch for: No detailed measurement caveats are currently recorded.
Buy the Monoprice SW-15. It ranks higher for sound quality than the XTZ Sound 99 W12S and costs less, so the other one has nothing left to offer.
Looking for alternatives? See the complete Subwoofers rankings.
Specifications Side By Side
| Monoprice SW-15 | XTZ Sound 99 W12S | |
|---|---|---|
| Price | $374.99 | $1499 |
| Ranked | #13 of 145 in Medium Home Subwoofers (30-75 lbs) | #47 of 145 in Medium Home Subwoofers (30-75 lbs) |
| Enclosure | ported, bottom | ported, rear |
| Output SPL at 15 Hz | 90.0 dB | - |
| Output SPL at 20 Hz | 101.2 dB | 74.0 dB |
| Output SPL at 25 Hz | 106.3 dB | 86.5 dB |
| Output SPL at 31.5 Hz | 111.2 dB | 97.7 dB |
| Output SPL at 40 Hz | 116.0 dB | 108.3 dB |
| Output SPL at 50 Hz | 120.2 dB | 114.9 dB |
| Output SPL at 63 Hz | 120.5 dB | 117.3 dB |
| Output SPL at 80 Hz | 119.5 dB | 117.4 dB |
| CEA-2010-A Average (40-80Hz) | 119.0 dB | 114.5 dB |
| Dimensions | 18.1"H x 21"W x 22.7"D (459.7 x 533.4 x 576.6 mm) | 19.6"H x 13.8"W x 15.7"D (499.1 x 349.8 x 400.0 mm) |
| Weight | 66.1 lbs (30.0 kg) | 67.2 lbs (30.5 kg) |
| Warranty | 1 | - |
| Cabinet Color | black | - |
| Country | United States | Sweden |
| Measurement Source | Audioholics | Ilkka Rissanen |
| Frequency Response | 30-150Hz (-10dB) | Not fully specified |
| Amplifier Power | 600W RMS / 800W peak | Not fully specified |
| Crossover Frequency | 40-150Hz, 18dB/octave | - |
| Phase Control | 0° or 180° | - |
| Inputs | Stereo line level and speaker level | - |
| Drivers | 15" (381mm) driver | 12" (305mm) driver |
Related Speaker Comparisons
How Monoprice SW-15 compares with other leading options:
- JTR Speakers Captivator 212PRO vs Monoprice SW-15
- MartinLogan Dynamo 1600X vs Monoprice SW-15
- HSU Research ULS-15 MK2 vs Monoprice SW-15
- Monoprice SW-15 vs PSB Speakers SubSeries 450
- Monoprice SW-12 vs Monoprice SW-15
Prices on this page were last checked September 14, 2026 at 1:47 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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The Two Speakers In Full
Monoprice SW-15: $374.99 Amazon eBay
Pros: 15-inch ported with 600W RMS (800W peak) delivers Large-room Bassaholic rating. Unrivaled mid-bass punch for $375. Strong output with clean control. Dual speaker-level inputs and 40-150Hz crossover for flexible hookup.
Cons: Budget-tier design, ported room gain dependency, 30 kg mid-size, and limited dynamic headroom.
Notes: Product # 41499
Full Monoprice SW-15 review and specifications →
| Amplifier Power | 600W RMS / 800W peak |
|---|---|
| CEA-2010-A Average (40-80Hz) | 119.0 dB |
| Cabinet Color | black |
| Country | United States |
| Crossover Frequency | 40-150Hz, 18dB/octave |
| Dimensions | 18.1"H x 21"W x 22.7"D (459.7 x 533.4 x 576.6 mm) |
| Drivers | 15" (381mm) driver |
| Enclosure | ported, bottom |
| Frequency Response | 30-150Hz (-10dB) |
| Inputs | Stereo line level and speaker level |
| Measurement Source | Audioholics |
| Output SPL at 15 Hz | 90.0 dB |
| Output SPL at 20 Hz | 101.2 dB |
| Output SPL at 25 Hz | 106.3 dB |
| Output SPL at 31.5 Hz | 111.2 dB |
| Output SPL at 40 Hz | 116.0 dB |
| Output SPL at 50 Hz | 120.2 dB |
| Output SPL at 63 Hz | 120.5 dB |
| Output SPL at 80 Hz | 119.5 dB |
| Phase Control | 0° or 180° |
| Warranty | 1 |
| Weight | 66.1 lbs (30.0 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Independently measured by Audioholics; the published figures above come from this ASR subwoofer measurement thread.
- Head-to-Head Comparisons
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- Monoprice SW-15 vs Power Sound Audio (PSA) XV15-BASE
- Monoprice SW-15 vs Paradigm Defiance X12
- Monoprice SW-15 vs Power Sound Audio (PSA) XS15-BASE
- Monoprice SW-15 vs Power Sound Audio (PSA) XV15
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XTZ Sound 99 W12S: $1499 eBay
Pros: 12-inch ported with Bang & Olufsen ICEpower half-kilowatt amplification. Sweepable phase knob with flexible EQ1/EQ2 switches for refined tuning. Excellent value high-output performance with powerful, clean amplification.
Full XTZ Sound 99 W12S review and specifications →
| Amplifier Power | Not fully specified |
|---|---|
| CEA-2010-A Average (40-80Hz) | 114.5 dB |
| Country | Sweden |
| Dimensions | 19.6"H x 13.8"W x 15.7"D (499.1 x 349.8 x 400.0 mm) |
| Drivers | 12" (305mm) driver |
| Enclosure | ported, rear |
| Frequency Response | Not fully specified |
| Measurement Source | Ilkka Rissanen |
| Output SPL at 20 Hz | 74.0 dB |
| Output SPL at 25 Hz | 86.5 dB |
| Output SPL at 31.5 Hz | 97.7 dB |
| Output SPL at 40 Hz | 108.3 dB |
| Output SPL at 50 Hz | 114.9 dB |
| Output SPL at 63 Hz | 117.3 dB |
| Output SPL at 80 Hz | 117.4 dB |
| Weight | 67.2 lbs (30.5 kg) |
- Reviews, Comparisons and Sound Samples
- Independently measured by Ilkka Rissanen; the published figures above come from this ASR subwoofer measurement thread.
- Head-to-Head Comparisons