Short answer: the Monoprice Monolith M-215 has been measured and ranked among subwoofers; the SVS SB17-Ultra R-Evolution has not been independently measured yet, so until it is, this comes down to features and price.
The case for the SVS SB17-Ultra R-Evolution: Sealed 17-inch high-excursion driver with dual 8-inch voice coils, driven by a 2,800W RMS dual-monoblock amplifier.
On the Monoprice Monolith M-215 side: Independent CEA-2010 testing records 118.9 dB at 20 Hz and 125.9 dB through 40-80 Hz.
Price: the SVS SB17-Ultra R-Evolution lists at $2,699.99 and the Monoprice Monolith M-215 at $2,999.99.
Buy the Monoprice Monolith M-215 if you want a speaker whose sound quality has been measured and ranked.
Buy the SVS SB17-Ultra R-Evolution if you prefer its design or features, and you can wait for measurements to confirm how it sounds.
Still deciding? The full Subwoofers rankings cover every ranked option.
Specifications Side By Side
| SVS SB17-Ultra R-Evolution | Monoprice Monolith M-215 | |
|---|---|---|
| Price | $2,699.99 | $2999.99 |
| Ranked | - | #23 of 109 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | ported, front |
| Drivers | 17” driver, dual 8” voice coils | 2x 15” (381mm) drivers |
| Amplifier Power | 2800W RMS | - |
| Frequency Response | 15Hz extension (manufacturer specified) | - |
| Cabinet Color | Piano Gloss Black, Black Oak Veneer | black |
| Country | United States | United States |
| Output SPL at 12.5 Hz | - | 103.9 dB |
| Output SPL at 15 Hz | - | 113.1 dB |
| Output SPL at 20 Hz | - | 118.9 dB |
| Output SPL at 25 Hz | - | 122.6 dB |
| Output SPL at 31.5 Hz | - | 125.2 dB |
| Output SPL at 40 Hz | - | 126.4 dB |
| Output SPL at 50 Hz | - | 126.1 dB |
| Output SPL at 63 Hz | - | 125.6 dB |
| Output SPL at 80 Hz | - | 125.6 dB |
| Output SPL at 100 Hz | - | 125.7 dB |
| Output SPL at 125 Hz | - | 126.3 dB |
| CEA-2010-A Average (40-80Hz) | - | 125.9 dB |
| Dimensions | - | 42.3”H x 20”W x 27.6”D (1074.4 x 508.0 x 701.0 mm) |
| Weight | - | 216.1 lbs (98.0 kg) |
| Warranty | - | 5 |
| Measurement Source | - | Brent Butterworth |
Prices on this page were last checked September 29, 2026 at 3:43 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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The Two Speakers In Full
SVS SB17-Ultra R-Evolution: $2,699.99 SVS eBay
Older models: the SVS SB16-Ultra (rated 4.1/5) and the SVS SB13-Ultra (rated 4.1/5).
Pros: Sealed 17-inch high-excursion driver with dual 8-inch voice coils, driven by a 2,800W RMS dual-monoblock amplifier. SVS rates extension to 15Hz. The SVS Subwoofer app adds DSP control and Auto EQ room calibration. It replaces the SB16-Ultra, whose ported sibling the PB17-Ultra R-Evolution has been measured and ranked.
Cons: No independent measurements yet, so its output can’t be compared with ranked subwoofers. A sealed flagship at this price gives up deep output against ported designs of the same size, so a large room may still call for two.
Full SVS SB17-Ultra R-Evolution review and specifications →
| Amplifier Power | 2800W RMS |
|---|---|
| Cabinet Color | Piano Gloss Black, Black Oak Veneer |
| Country | United States |
| Drivers | 17” driver, dual 8” voice coils |
| Enclosure | sealed |
| Frequency Response | 15Hz extension (manufacturer specified) |
- Links
- Reviews, Comparisons and Sound Samples
- These figures are manufacturer-specified rather than independently measured.
- Head-to-Head Comparisons
Monoprice Monolith M-215: $2999.99 Monoprice eBay
Pros: Independent CEA-2010 testing records 118.9 dB at 20 Hz and 125.9 dB through 40-80 Hz. The ported, front enclosure with 2x 15” (381mm) drivers has the headroom for demanding film bass in a large room.
Cons: The 1074.4H x 508.0W x 701.0D mm cabinet and 98.0 kg mass make this a serious placement and moving commitment. Ported output does not solve room modes, so careful placement and calibration remain essential.
Notes: Product # 38543
Full Monoprice Monolith M-215 review and specifications →
| CEA-2010-A Average (40-80Hz) | 125.9 dB |
|---|---|
| Cabinet Color | black |
| Country | United States |
| Dimensions | 42.3”H x 20”W x 27.6”D (1074.4 x 508.0 x 701.0 mm) |
| Drivers | 2x 15” (381mm) drivers |
| Enclosure | ported, front |
| Measurement Source | Brent Butterworth |
| Output SPL at 12.5 Hz | 103.9 dB |
| Output SPL at 15 Hz | 113.1 dB |
| Output SPL at 20 Hz | 118.9 dB |
| Output SPL at 25 Hz | 122.6 dB |
| Output SPL at 31.5 Hz | 125.2 dB |
| Output SPL at 40 Hz | 126.4 dB |
| Output SPL at 50 Hz | 126.1 dB |
| Output SPL at 63 Hz | 125.6 dB |
| Output SPL at 80 Hz | 125.6 dB |
| Output SPL at 100 Hz | 125.7 dB |
| Output SPL at 125 Hz | 126.3 dB |
| Warranty | 5 |
| Weight | 216.1 lbs (98.0 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Independently measured by Brent Butterworth; the published figures above come from this ASR subwoofer measurement thread.
- Head-to-Head Comparisons
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