Short answer: the SVS SB16-Ultra has been measured and ranked; the JTR Kallos 12Sub has not been measured in a way we can rank yet, so until it is, this comes down to features and price.
What the JTR Kallos 12Sub offers: A compact sealed subwoofer with a 12-inch driver and a 2,000W RMS Class D amplifier, with DSP tuning for a smooth response and high output.
On the SVS SB16-Ultra side: Independent CEA-2010 testing records 103.1 dB at 20 Hz and 119.0 dB through 40-80 Hz.
Price: the JTR Kallos 12Sub lists at $3,699 and the SVS SB16-Ultra at $2,300.
Buy the SVS SB16-Ultra if you want a speaker whose sound quality has been measured and ranked.
Buy the JTR Kallos 12Sub if you prefer its design or features, and you can wait for measurements to confirm how it sounds.
Still deciding? The full Subwoofers rankings cover every ranked option.
Specifications Side By Side
| JTR Kallos 12Sub | SVS SB16-Ultra | |
|---|---|---|
| Price | $3,699 | $2,300 Discontinued |
| Ranked | - | #73 of 109 in Large Home Subwoofers (Over 75 lbs) |
| Drivers | 12” (305mm) driver | 16” (406mm) driver |
| Amplifier Power | 2000W RMS (Class D) | - |
| Frequency Response | 22Hz - 800Hz (+/-3dB outdoor) (Manufacturer specified) | - |
| Enclosure | sealed | sealed |
| Dimensions | 18.7”H x 18.7”W x 12.8”D (476 x 476 x 324 mm) | 20”H x 19.5”W x 20.1”D (508.0 x 495.3 x 510.5 mm) |
| Cabinet Material | Stacked Baltic birch | - |
| Country | United States | United States |
| Output SPL at 10 Hz | - | 86.9 dB |
| Output SPL at 12.5 Hz | - | 91.8 dB |
| Output SPL at 15 Hz | - | 97.7 dB |
| Output SPL at 20 Hz | - | 103.1 dB |
| Output SPL at 25 Hz | - | 109.4 dB |
| Output SPL at 31.5 Hz | - | 116.1 dB |
| Output SPL at 40 Hz | - | 118.2 dB |
| Output SPL at 50 Hz | - | 119.2 dB |
| Output SPL at 63 Hz | - | 119.5 dB |
| Output SPL at 80 Hz | - | 119.0 dB |
| Output SPL at 100 Hz | - | 119.3 dB |
| Output SPL at 125 Hz | - | 119.8 dB |
| CEA-2010-A Average (40-80Hz) | - | 119.0 dB |
| Weight | - | 121.9 lbs (55.3 kg) |
| Warranty | - | 5 |
| Cabinet Color | - | black |
| Measurement Source | - | Audioholics |
| Inputs | - | XLR (balanced, LFE/stereo), RCA (LFE/stereo) |
| XLR Input | - | Yes |
| RCA Input | - | Yes |
| TRS Input | - | No |
| Optical Input | - | No |
| Coaxial Input | - | No |
| USB Input | - | No |
| HDMI Input | - | No |
| AES Input | - | No |
| Aux Input | - | No |
Prices on this page were last checked September 30, 2026 at 2:57 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
JTR Kallos 12Sub: $3,699 JTR Speakers eBay
Pros: A compact sealed subwoofer with a 12-inch driver and a 2,000W RMS Class D amplifier, with DSP tuning for a smooth response and high output. JTR rates it at 22Hz to 800Hz within 3dB outdoors, with in-room gain extending it lower. The cabinet is stacked Baltic birch, about 48cm square and 32cm deep.
Cons: Erin’s Audio Corner tested it outdoors on video, but CEA-2010 output figures in the form the other subwoofers here are ranked on haven’t been published, so it can’t be placed against them. At $3,699 it is expensive for a single 12-inch subwoofer, and it is sold mainly direct from JTR.
Full JTR Kallos 12Sub review and specifications →
| Amplifier Power | 2000W RMS (Class D) |
|---|---|
| Cabinet Material | Stacked Baltic birch |
| Country | United States |
| Dimensions | 18.7”H x 18.7”W x 12.8”D (476 x 476 x 324 mm) |
| Drivers | 12” (305mm) driver |
| Enclosure | sealed |
| Frequency Response | 22Hz - 800Hz (+/-3dB outdoor) (Manufacturer specified) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
SVS SB16-Ultra: $2,300 Discontinued eBay
Newer model: the SVS SB17-Ultra R-Evolution. It’s likely to perform similarly, though we don’t have measurements to confirm that yet.
Pros: Independent CEA-2010 testing records 103.1 dB at 20 Hz and 119.0 dB through 40-80 Hz. The sealed enclosure with 16” (406mm) driver delivers substantial 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 508.0H x 495.3W x 510.5D mm cabinet and 55.3 kg mass still require deliberate placement and calibration. Discontinued.
Full SVS SB16-Ultra review and specifications →
| AES Input | No |
|---|---|
| Aux Input | No |
| CEA-2010-A Average (40-80Hz) | 119.0 dB |
| Cabinet Color | black |
| Coaxial Input | No |
| Country | United States |
| Dimensions | 20”H x 19.5”W x 20.1”D (508.0 x 495.3 x 510.5 mm) |
| Drivers | 16” (406mm) driver |
| Enclosure | sealed |
| HDMI Input | No |
| Inputs | XLR (balanced, LFE/stereo), RCA (LFE/stereo) |
| Measurement Source | Audioholics |
| Optical Input | No |
| Output SPL at 10 Hz | 86.9 dB |
| Output SPL at 12.5 Hz | 91.8 dB |
| Output SPL at 15 Hz | 97.7 dB |
| Output SPL at 20 Hz | 103.1 dB |
| Output SPL at 25 Hz | 109.4 dB |
| Output SPL at 31.5 Hz | 116.1 dB |
| Output SPL at 40 Hz | 118.2 dB |
| Output SPL at 50 Hz | 119.2 dB |
| Output SPL at 63 Hz | 119.5 dB |
| Output SPL at 80 Hz | 119.0 dB |
| Output SPL at 100 Hz | 119.3 dB |
| Output SPL at 125 Hz | 119.8 dB |
| RCA Input | Yes |
| TRS Input | No |
| USB Input | No |
| Warranty | 5 |
| Weight | 121.9 lbs (55.3 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