Short answer: the JTR Speakers Captivator 2400. Both are rated 4.4/5 for sound quality (#20 and #19 of 110 subwoofers), and the JTR Speakers Captivator 2400 costs $3500 against $9487.26 for the Funk Audio Ultra 21.0LX, and with sound quality even, the cheaper one is the better buy.
Buy the JTR Speakers Captivator 2400. Both are rated the same for sound quality, and it costs $5987.26 less than the Funk Audio Ultra 21.0LX.
Still deciding? The full Subwoofers rankings cover every ranked option.
Specifications Side By Side
| Funk Audio Ultra 21.0LX | JTR Speakers Captivator 2400 | |
|---|---|---|
| Price | $9,487.26 | $3,500 |
| Ranked | #19 of 110 in Large Home Subwoofers (Over 75 lbs) | #20 of 110 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | ported, front |
| Output SPL at 10 Hz | 99.9 dB | 104.8 dB |
| Output SPL at 12.5 Hz | 102.3 dB | 109.1 dB |
| Output SPL at 15 Hz | 108.4 dB | 113.6 dB |
| Output SPL at 20 Hz | 116.6 dB | 115.5 dB |
| Output SPL at 25 Hz | 120.5 dB | 120.0 dB |
| Output SPL at 31.5 Hz | 121.2 dB | 123.3 dB |
| Output SPL at 40 Hz | 125.0 dB | 126.2 dB |
| Output SPL at 50 Hz | 127.2 dB | 126.7 dB |
| Output SPL at 63 Hz | 126.5 dB | 126.3 dB |
| Output SPL at 80 Hz | 126.6 dB | 125.8 dB |
| Output SPL at 100 Hz | 127.6 dB | 125.8 dB |
| CEA-2010-A Average (40-80Hz) | 126.3 dB | 126.2 dB |
| Dimensions | 25.5"H x 24.5"W x 24"D (647.7 x 622.3 x 609.6 mm) | 30"H x 20"W x 22.5"D (762.0 x 508.0 x 571.5 mm) |
| Weight | 145.1 lbs (65.8 kg) | 147.9 lbs (67.1 kg) |
| Warranty | 3 | 5/3 |
| Cabinet Color | wood, custom | black, custom |
| Country | Canada | United States |
| Measurement Source | Manufacturer | Audioholics |
| Drivers | 21" (533mm) driver | 18" (457mm) driver |
| Inputs | XLR (balanced) | XLR, RCA |
| XLR Input | Yes | Yes |
| RCA Input | No | Yes |
| TRS Input | No | No |
| Optical Input | No | No |
| Coaxial Input | No | No |
| USB Input | No | No |
| HDMI Input | No | No |
| AES Input | No | No |
| Aux Input | No | No |
| Output SPL at 125 Hz | - | 124.2 dB |
Related Speaker Comparisons
More top alternatives to Funk Audio Ultra 21.0LX:
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- Funk Audio Ultra 21.0LX vs Monoprice Monolith 16 THX Ultra
- Funk Audio Ultra 21.0LX vs Reaction Audio PV-15X
- HSU Research VTF-3 MK5 HP vs Funk Audio Ultra 21.0LX
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
JTR Speakers Captivator 2400: $3,500 eBay
Pros: Independent CEA-2010 testing records 115.5 dB at 20 Hz and 126.2 dB through 40-80 Hz. The ported, front enclosure with 18” (457mm) driver has the headroom for demanding film bass in a large room.
Cons: The 762.0H x 508.0W x 571.5D mm cabinet and 67.1 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 JTR Speakers Captivator 2400 review and specifications →
| AES Input | No |
|---|---|
| Aux Input | No |
| CEA-2010-A Average (40-80Hz) | 126.2 dB |
| Cabinet Color | black, custom |
| Coaxial Input | No |
| Country | United States |
| Dimensions | 30"H x 20"W x 22.5"D (762.0 x 508.0 x 571.5 mm) |
| Drivers | 18" (457mm) driver |
| Enclosure | ported, front |
| HDMI Input | No |
| Inputs | XLR, RCA |
| Measurement Source | Audioholics |
| Optical Input | No |
| Output SPL at 10 Hz | 104.8 dB |
| Output SPL at 12.5 Hz | 109.1 dB |
| Output SPL at 15 Hz | 113.6 dB |
| Output SPL at 20 Hz | 115.5 dB |
| Output SPL at 25 Hz | 120.0 dB |
| Output SPL at 31.5 Hz | 123.3 dB |
| Output SPL at 40 Hz | 126.2 dB |
| Output SPL at 50 Hz | 126.7 dB |
| Output SPL at 63 Hz | 126.3 dB |
| Output SPL at 80 Hz | 125.8 dB |
| Output SPL at 100 Hz | 125.8 dB |
| Output SPL at 125 Hz | 124.2 dB |
| RCA Input | Yes |
| TRS Input | No |
| USB Input | No |
| Warranty | 5/3 |
| Weight | 147.9 lbs (67.1 kg) |
| XLR Input | Yes |
- Links
- Reviews, Comparisons and Sound Samples
- Independently measured by Audioholics; the published figures above come from this ASR subwoofer measurement thread.
- Head-to-Head Comparisons