The Monoprice Monolith 15 THX Ultra is rated 4.2/5 for sound quality, #66 of 143 Large Home Subwoofers (Over 75 lbs). See all Subwoofers rankings for every top pick.
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Brand: Monoprice
#66 Monoprice Monolith 15 THX Ultra: $1,999 Discontinued eBay
Newer model: the Monoprice Monolith M-15 V2, ranked lower, rated 4.2/5, released Nov 2021 (also discontinued). See every Monoprice Monolith generation.
Same family: the Monoprice Monolith 12 THX Ultra (smaller subwoofer, ranked lower, rated 3.8/5), the Monoprice Monolith 13 THX Ultra (smaller subwoofer, ranked higher, rated 4.2/5) and the Monoprice Monolith 16 THX Ultra (larger subwoofer, ranked higher, rated 4.4/5).
Pros: A THX Ultra certified 15 inch ported subwoofer with strong deep bass for home theaters, a good buy used. Independent CEA-2010 testing records 110.0 dB at 20 Hz and 120.5 dB through 40-80 Hz. The ported, front enclosure with 15” (381mm) driver has the headroom for demanding film bass in a large room.
Cons: The 680.7H x 449.6W x 701.0D mm cabinet and 58.3 kg mass make this a serious placement and moving commitment. Ported output does not solve room modes, so careful placement and calibration remain essential. Discontinued.
Notes: Product # 24458
Is the Monoprice Monolith 15 THX Ultra right for you?
Skip it if
- you need to move it often (58 kg each).
- you want to buy it new: it is discontinued.
| Released | 2017 (9 years ago) |
|---|---|
| AES Input | No |
| Aux Input | No |
| CEA-2010-A Average (40-80Hz) | 120.5 dB |
| Cabinet Color | black |
| Coaxial Input | No |
| Country | United States |
| Dimensions | 26.8”H x 17.7”W x 27.6”D (680.7 x 449.6 x 701.0 mm) |
| Drivers | 15” (381mm) driver |
| Enclosure | ported, front |
| HDMI Input | No |
| Inputs | XLR, RCA |
| Measurement Source | ErinsAudioCorner |
| Optical Input | No |
| Output SPL at 12.5 Hz | 90.0 dB |
| Output SPL at 15 Hz | 100.8 dB |
| Output SPL at 20 Hz | 110.0 dB |
| Output SPL at 25 Hz | 115.6 dB |
| Output SPL at 31.5 Hz | 118.0 dB |
| Output SPL at 40 Hz | 122.0 dB |
| Output SPL at 50 Hz | 121.0 dB |
| Output SPL at 63 Hz | 120.0 dB |
| Output SPL at 80 Hz | 119.0 dB |
| Output SPL at 100 Hz | 119.0 dB |
| Output SPL at 125 Hz | 118.0 dB |
| RCA Input | Yes |
| TRS Input | No |
| USB Input | No |
| Warranty | 5 |
| Weight | 128.5 lbs (58.3 kg) |
| XLR Input | Yes |
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Head-to-Head Comparisons
2 comparisons- Monoprice Monolith 15 THX Ultra vs Klipsch RP-1600SW
- Monoprice Monolith 15 THX Ultra vs Monoprice Monolith 16 THX Ultra
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