Short answer: the Funk Audio Ultra 21.0LX. Both are rated 4.4/5 for sound quality (#19 and #17 of 110 subwoofers), and the Funk Audio Ultra 21.0LX costs $9487.26 against $10078.84 for the Harbottle Audio C24 L2, with sound quality a draw, the lower price decides it.
Buy the Funk Audio Ultra 21.0LX. Both are rated the same for sound quality, and it costs $591.58 less than the Harbottle Audio C24 L2.
Still deciding? The full Subwoofers rankings cover every ranked option.
Specifications Side By Side
| Funk Audio Ultra 21.0LX | Harbottle Audio C24 L2 | |
|---|---|---|
| Price | $9,487.26 | $10,078.84 |
| Ranked | #19 of 110 in Large Home Subwoofers (Over 75 lbs) | #17 of 110 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | ported |
| Output SPL at 10 Hz | 99.9 dB | 99.0 dB |
| Output SPL at 12.5 Hz | 102.3 dB | 103.0 dB |
| Output SPL at 15 Hz | 108.4 dB | 110.0 dB |
| Output SPL at 20 Hz | 116.6 dB | 117.0 dB |
| Output SPL at 25 Hz | 120.5 dB | 120.7 dB |
| Output SPL at 31.5 Hz | 121.2 dB | 124.0 dB |
| Output SPL at 40 Hz | 125.0 dB | 126.3 dB |
| Output SPL at 50 Hz | 127.2 dB | 127.3 dB |
| Output SPL at 63 Hz | 126.5 dB | 126.7 dB |
| Output SPL at 80 Hz | 126.6 dB | 126.0 dB |
| Output SPL at 100 Hz | 127.6 dB | 125.0 dB |
| CEA-2010-A Average (40-80Hz) | 126.3 dB | 126.6 dB |
| Dimensions | 25.5"H x 24.5"W x 24"D (647.7 x 622.3 x 609.6 mm) | 35.4"H x 28.4"W x 20.2"D (899.9 x 722.1 x 512.1 mm) |
| Weight | 145.1 lbs (65.8 kg) | 149.9 lbs (68.0 kg) |
| Warranty | 3 | - |
| Cabinet Color | wood, custom | black, white, red, blue |
| Country | Canada | Canada |
| Measurement Source | Manufacturer | Manufacturer |
| Drivers | 21" (533mm) driver | 24" (610mm) driver |
| Inputs | XLR (balanced) | - |
| XLR Input | Yes | - |
| RCA Input | No | - |
| TRS Input | No | - |
| Optical Input | No | - |
| Coaxial Input | No | - |
| USB Input | No | - |
| HDMI Input | No | - |
| AES Input | No | - |
| Aux Input | No | - |
Related Speaker Comparisons
How Harbottle Audio C24 L2 compares with other leading options:
- JTR Speakers Captivator S2 vs Harbottle Audio C24 L2
- Funk Audio Custom 21.0 vs Harbottle Audio C24 L2
- Funk Audio Classic 18.0 vs Harbottle Audio C24 L2
- Harbottle Audio C24 L2 vs Monoprice Monolith 16 THX Ultra
- HSU Research VTF-3 MK5 HP vs Harbottle Audio C24 L2
Prices on this page were last checked September 23, 2026 at 11:24 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
Funk Audio Ultra 21.0LX: $9,487.26 eBay
Pros: Published CEA-2010 specifications list 116.6 dB at 20 Hz and 126.3 dB through 40-80 Hz. The sealed enclosure with 21” (533mm) driver has the headroom for demanding film bass in a large room.
Cons: The 647.7H x 622.3W x 609.6D mm cabinet and 65.8 kg mass make this a serious placement and moving commitment. A sealed cabinet still needs careful placement and calibration to avoid room-mode peaks.
Full Funk Audio Ultra 21.0LX review and specifications →
| AES Input | No |
|---|---|
| Aux Input | No |
| CEA-2010-A Average (40-80Hz) | 126.3 dB |
| Cabinet Color | wood, custom |
| Coaxial Input | No |
| Country | Canada |
| Dimensions | 25.5"H x 24.5"W x 24"D (647.7 x 622.3 x 609.6 mm) |
| Drivers | 21" (533mm) driver |
| Enclosure | sealed |
| HDMI Input | No |
| Inputs | XLR (balanced) |
| Measurement Source | Manufacturer |
| Optical Input | No |
| Output SPL at 10 Hz | 99.9 dB |
| Output SPL at 12.5 Hz | 102.3 dB |
| Output SPL at 15 Hz | 108.4 dB |
| Output SPL at 20 Hz | 116.6 dB |
| Output SPL at 25 Hz | 120.5 dB |
| Output SPL at 31.5 Hz | 121.2 dB |
| Output SPL at 40 Hz | 125.0 dB |
| Output SPL at 50 Hz | 127.2 dB |
| Output SPL at 63 Hz | 126.5 dB |
| Output SPL at 80 Hz | 126.6 dB |
| Output SPL at 100 Hz | 127.6 dB |
| RCA Input | No |
| TRS Input | No |
| USB Input | No |
| Warranty | 3 |
| Weight | 145.1 lbs (65.8 kg) |
| XLR Input | Yes |
- Links
- Reviews, Comparisons and Sound Samples
- These figures are manufacturer-specified rather than independently measured.
- Head-to-Head Comparisons
Harbottle Audio C24 L2: $10,078.84 eBay
Pros: Published CEA-2010 specifications list 117.0 dB at 20 Hz and 126.6 dB through 40-80 Hz. The ported enclosure with 24” (610mm) driver has the headroom for demanding film bass in a large room.
Cons: The 899.9H x 722.1W x 512.1D mm cabinet and 68.0 kg mass make this a serious placement and moving commitment. Ported output does not solve room modes, so careful placement and calibration remain essential.
Full Harbottle Audio C24 L2 review and specifications →
| CEA-2010-A Average (40-80Hz) | 126.6 dB |
|---|---|
| Cabinet Color | black, white, red, blue |
| Country | Canada |
| Dimensions | 35.4"H x 28.4"W x 20.2"D (899.9 x 722.1 x 512.1 mm) |
| Drivers | 24" (610mm) driver |
| Enclosure | ported |
| Measurement Source | Manufacturer |
| Output SPL at 10 Hz | 99.0 dB |
| Output SPL at 12.5 Hz | 103.0 dB |
| Output SPL at 15 Hz | 110.0 dB |
| Output SPL at 20 Hz | 117.0 dB |
| Output SPL at 25 Hz | 120.7 dB |
| Output SPL at 31.5 Hz | 124.0 dB |
| Output SPL at 40 Hz | 126.3 dB |
| Output SPL at 50 Hz | 127.3 dB |
| Output SPL at 63 Hz | 126.7 dB |
| Output SPL at 80 Hz | 126.0 dB |
| Output SPL at 100 Hz | 125.0 dB |
| Weight | 149.9 lbs (68.0 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- These figures are manufacturer-specified rather than independently measured.
- Head-to-Head Comparisons