Short answer: the Harbinger V2218S for better sound quality, the Monoprice Monolith M-215 for the lower price. The Harbinger V2218S ranks #15 of 110 subwoofers at $3495. The Monoprice Monolith M-215 ranks #23 at $2999.99, $495.01 cheaper.
What the Harbinger V2218S offers: Independent CEA-2010 testing records 81.7 dB at 20 Hz and 128.9 dB through 40-80 Hz. The ported, front enclosure with 18” (457mm) driver delivers formidable upper-bass output for movie effects and music. Watch for: 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 825.5H x 673.1W x 754.4D mm cabinet and 40.8 kg mass still require deliberate placement and calibration.
What the Monoprice Monolith M-215 offers: 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. Watch for: 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.
Buy the Harbinger V2218S when sound quality outweighs the price for you, and the Monoprice Monolith M-215 when the price outweighs sound quality instead.
Want more options? Browse the full Subwoofers rankings.
Specifications Side By Side
| Harbinger V2218S | Monoprice Monolith M-215 | |
|---|---|---|
| Price | $3495 | $2999.99 |
| Ranked | #15 of 110 in Large Home Subwoofers (Over 75 lbs) | #23 of 110 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | ported, front | ported, front |
| Output SPL at 20 Hz | 81.7 dB | 118.9 dB |
| Output SPL at 25 Hz | 99.7 dB | 122.6 dB |
| Output SPL at 31.5 Hz | 118.0 dB | 125.2 dB |
| Output SPL at 40 Hz | 122.8 dB | 126.4 dB |
| Output SPL at 50 Hz | 129.0 dB | 126.1 dB |
| Output SPL at 63 Hz | 132.2 dB | 125.6 dB |
| Output SPL at 80 Hz | 131.7 dB | 125.6 dB |
| CEA-2010-A Average (40-80Hz) | 128.9 dB | 125.9 dB |
| Dimensions | 32.5"H x 26.5"W x 29.7"D (825.5 x 673.1 x 754.4 mm) | 42.3"H x 20"W x 27.6"D (1074.4 x 508.0 x 701.0 mm) |
| Weight | 89.9 lbs (40.8 kg) | 216.1 lbs (98.0 kg) |
| Cabinet Color | black | black |
| Country | United States | United States |
| Measurement Source | Brent Butterworth | Brent Butterworth |
| Drivers | 18" (457mm) driver | 2x 15" (381mm) drivers |
| Output SPL at 12.5 Hz | - | 103.9 dB |
| Output SPL at 15 Hz | - | 113.1 dB |
| Output SPL at 100 Hz | - | 125.7 dB |
| Output SPL at 125 Hz | - | 126.3 dB |
| Warranty | - | 5 |
Related Speaker Comparisons
More worthwhile head-to-heads for Harbinger V2218S:
- Harbinger V2218S vs Funk Audio Ultra 24.0
- Harbinger V2218S vs JTR Speakers Growler (2015)
- Harbinger V2218S vs Funk Audio Classic 18.0
- Monoprice Monolith 16 THX Ultra vs Harbinger V2218S
- Rythmik FV25HP vs Harbinger V2218S
Prices on this page were last checked September 16, 2026 at 12:41 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
Harbinger V2218S: $3495 eBay
Pros: Independent CEA-2010 testing records 81.7 dB at 20 Hz and 128.9 dB through 40-80 Hz. The ported, front enclosure with 18” (457mm) driver delivers formidable upper-bass output for movie effects and music.
Cons: 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 825.5H x 673.1W x 754.4D mm cabinet and 40.8 kg mass still require deliberate placement and calibration.
Notes: Looks like “PA sub”
Full Harbinger V2218S review and specifications →
| CEA-2010-A Average (40-80Hz) | 128.9 dB |
|---|---|
| Cabinet Color | black |
| Country | United States |
| Dimensions | 32.5"H x 26.5"W x 29.7"D (825.5 x 673.1 x 754.4 mm) |
| Drivers | 18" (457mm) driver |
| Enclosure | ported, front |
| Measurement Source | Brent Butterworth |
| Output SPL at 20 Hz | 81.7 dB |
| Output SPL at 25 Hz | 99.7 dB |
| Output SPL at 31.5 Hz | 118.0 dB |
| Output SPL at 40 Hz | 122.8 dB |
| Output SPL at 50 Hz | 129.0 dB |
| Output SPL at 63 Hz | 132.2 dB |
| Output SPL at 80 Hz | 131.7 dB |
| Weight | 89.9 lbs (40.8 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
- Harbinger V2218S vs Funk Audio Classic 18.0
- Harbinger V2218S vs JTR Speakers Growler (2015)
- Harbinger V2218S vs Monoprice Monolith 16 THX Ultra
- Harbinger V2218S vs Funk Audio Ultra 24.0
- Harbinger V2218S vs Rythmik FV25HP
- Harbinger V2218S vs JTR Speakers Captivator 1400
- Harbinger V2218S vs JTR Speakers Captivator 2400ULF
- Harbinger V2218S vs Rythmik FV15HP
- See all 14 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
- Monoprice Monolith M-215 vs Rythmik FV25HP
- Monoprice Monolith M-215 vs Reaction Audio PV-15X
- Monoprice Monolith M-215 vs XTZ Sound SUB 3X12
- Monoprice Monolith M-215 vs Monoprice Monolith 16 THX Ultra
- Monoprice Monolith M-215 vs JTR Speakers Captivator 1400
- Monoprice Monolith M-215 vs Funk Audio Classic 18.0
- Monoprice Monolith M-215 vs JTR Speakers Growler (2015)
- Monoprice Monolith M-215 vs Funk Audio Ultra 24.0
- See all 25 comparisons