Short answer: the Rythmik FV15HP for the higher ranking, the Monoprice Monolith M15-S for the lower price. The Rythmik FV15HP ranks #39 of 97 subwoofers at $1770. The Monoprice Monolith M15-S ranks #62 at $999, $771 cheaper.
On the Rythmik FV15HP side: 15-inch ported driver reaches 122.0dB CEA-2010-A average, matching the output of subwoofers costing significantly more. The tradeoff: Premium price ($1,770), ported design room gain dependency, and mid-to-large 52 kg footprint.
Buy the Monoprice Monolith M15-S if the price matters more than the ranking. Buy the Rythmik FV15HP if the ranking matters more than the price.
Specifications Side By Side
| Monoprice Monolith M15-S | Rythmik FV15HP | |
|---|---|---|
| Price | $999 | $1,770 |
| Ranked | #62 of 97 in Large Powered Home Subwoofers (Over 75 lbs) | #39 of 97 in Large Powered Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | ported, front |
| Output SPL at 15 Hz | 100.1 dB | 105.1 dB |
| Output SPL at 20 Hz | 105.6 dB | 111.1 dB |
| Output SPL at 25 Hz | 111.2 dB | 116.1 dB |
| Output SPL at 31.5 Hz | 115.2 dB | 120.0 dB |
| Output SPL at 40 Hz | 118.4 dB | 122.5 dB |
| Output SPL at 50 Hz | 119.3 dB | 122.1 dB |
| Output SPL at 63 Hz | 119.6 dB | 121.8 dB |
| Output SPL at 80 Hz | 118.9 dB | 121.4 dB |
| Output SPL at 100 Hz | 119.1 dB | 121.2 dB |
| Output SPL at 125 Hz | 118.9 dB | 121.1 dB |
| CEA-2010-A Average (40-80Hz) | 119.0 dB | 122.0 dB |
| Dimensions | 23.5"H x 16.7"W x 19.7"D (596.9 x 424.2 x 500.4 mm) | 24.5"H x 18.25"W x 24.25"D (622.3 x 463.5 x 615.9 mm) |
| Warranty | 5 | 5/3 |
| Country | United States | United States |
| Measurement Source | Manufacturer | Audioholics |
| Weight | 80 lbs / 36.3 kg | 115.1 lbs / 52.2 kg |
| Drivers | 15" (381mm) driver | 15" (381mm) driver |
| Output SPL at 12.5 Hz | - | 92.8 dB |
| Cabinet Color | - | black, white |
The Two Speakers In Full
Monoprice Monolith M15-S: $999
Notes: Product # 35141
| CEA-2010-A Average (40-80Hz) | 119.0 dB |
|---|---|
| Country | United States |
| Dimensions | 23.5"H x 16.7"W x 19.7"D (596.9 x 424.2 x 500.4 mm) |
| Drivers | 15" (381mm) driver |
| Enclosure | sealed |
| Measurement Source | Manufacturer |
| Output SPL at 15 Hz | 100.1 dB |
| Output SPL at 20 Hz | 105.6 dB |
| Output SPL at 25 Hz | 111.2 dB |
| Output SPL at 31.5 Hz | 115.2 dB |
| Output SPL at 40 Hz | 118.4 dB |
| Output SPL at 50 Hz | 119.3 dB |
| Output SPL at 63 Hz | 119.6 dB |
| Output SPL at 80 Hz | 118.9 dB |
| Output SPL at 100 Hz | 119.1 dB |
| Output SPL at 125 Hz | 118.9 dB |
| Warranty | 5 |
| Weight | 80 lbs / 36.3 kg |
- Head-to-Head Comparisons
- Monoprice Monolith M15-S vs Rythmik F18
- Monoprice Monolith M15-S vs Monoprice Monolith M-15 V2
- Monoprice Monolith M15-S vs SVS PB-4000
- Monoprice Monolith M15-S vs HSU Research VTF-3 MK5 HP
- Monoprice Monolith M15-S vs HSU Research VTF-15H MK2
- Monoprice Monolith M15-S vs Monoprice Monolith M-215
- Monoprice Monolith M15-S vs Reaction Audio PV-15X
- Monoprice Monolith M15-S vs Monoprice Monolith 16 THX Ultra
- See all 15 comparisons
- Links
Rythmik FV15HP: $1,770
Pros: 15-inch ported driver reaches 122.0dB CEA-2010-A average, matching the output of subwoofers costing significantly more.
Cons: Premium price ($1,770), ported design room gain dependency, and mid-to-large 52 kg footprint.
| CEA-2010-A Average (40-80Hz) | 122.0 dB |
|---|---|
| Cabinet Color | black, white |
| Country | United States |
| Dimensions | 24.5"H x 18.25"W x 24.25"D (622.3 x 463.5 x 615.9 mm) |
| Drivers | 15" (381mm) driver |
| Enclosure | ported, front |
| Measurement Source | Audioholics |
| Output SPL at 12.5 Hz | 92.8 dB |
| Output SPL at 15 Hz | 105.1 dB |
| Output SPL at 20 Hz | 111.1 dB |
| Output SPL at 25 Hz | 116.1 dB |
| Output SPL at 31.5 Hz | 120.0 dB |
| Output SPL at 40 Hz | 122.5 dB |
| Output SPL at 50 Hz | 122.1 dB |
| Output SPL at 63 Hz | 121.8 dB |
| Output SPL at 80 Hz | 121.4 dB |
| Output SPL at 100 Hz | 121.2 dB |
| Output SPL at 125 Hz | 121.1 dB |
| Warranty | 5/3 |
| Weight | 115.1 lbs / 52.2 kg |
- Head-to-Head Comparisons
- Rythmik FV15HP vs HSU Research VTF-15H MK2
- Rythmik FV15HP vs HSU Research VTF-3 MK5 HP
- Rythmik FV15HP vs SVS PB-4000
- Rythmik FV15HP vs Monoprice Monolith M-15 V2
- Rythmik FV15HP vs Monoprice Monolith M-215
- Rythmik FV15HP vs Rythmik F18
- Rythmik FV15HP vs Reaction Audio PV-15X
- Rythmik FV15HP vs Monoprice Monolith 16 THX Ultra
- See all 13 comparisons
- Links
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Product prices and availability were last checked August 9, 2026 at 6:57 AM UTC 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.

