Short answer: both are discontinued, so this only matters if you are buying used. Used, the JBL 4645C is the better pick: it ranks #25 of 143 subwoofers by sound quality (rated 4.4/5), against #57 (rated 4.2/5) for the HSU Research VTF-15H MK2. If you want one new, the HSU Research VTF-TN1 replaces the HSU Research VTF-15H MK2 and is rated 3.9/5 at $1,249.
The case for the HSU Research VTF-15H MK2: A 15 inch ported subwoofer from a long running series, with strong output for movies at a reasonable price. The tradeoff: Ported enclosure prone to room modes at certain frequencies, mid-large 110.2 lbs (50 kg) size, and $1499 price point.
Why pick the JBL 4645C: A pro cinema 18 inch ported subwoofer with very strong upper bass punch, suited to adding impact in a modest room. The tradeoff: Deep-bass output is limited relative to its midbass result, so it is not the right choice for the lowest movie effects.
Buy the JBL 4645C only if you find one used in good condition; both are discontinued, and it is the better rated of the two. For a new speaker, buy the HSU Research VTF-TN1, which replaces the HSU Research VTF-15H MK2.
Want more options? Browse the full Subwoofers rankings.
A 15 inch ported subwoofer from a long running series, with strong output for movies at a reasonable price.
Prices on this page were last checked October 31, 2026 at 7:11 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.
As an eBay Partner, we may be compensated if you make a purchase.
Specifications Side By Side
| HSU Research VTF-15H MK2 | JBL 4645C | |
|---|---|---|
| Price | $1,499 Discontinued | $4,999 Passive, Discontinued |
| Ranked | #57 of 143 in Large Home Subwoofers (Over 75 lbs) | #25 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | ported, front | ported, front |
| Output SPL at 15 Hz | 101.6 dB | - |
| Output SPL at 20 Hz | 108.4 dB | 98.9 dB |
| Output SPL at 25 Hz | 114.8 dB | 114.0 dB |
| Output SPL at 31.5 Hz | 119.4 dB | 118.7 dB |
| Output SPL at 40 Hz | 122.9 dB | 122.0 dB |
| Output SPL at 50 Hz | 122.5 dB | 123.7 dB |
| Output SPL at 63 Hz | 121.1 dB | 129.7 dB |
| Output SPL at 80 Hz | 120.5 dB | 133.9 dB |
| CEA-2010-A Average (40-80Hz) | 121.8 dB | 127.3 dB |
| Dimensions | 24”H x 18”W x 26”D (609.6 x 457.2 x 660.4 mm) | 39.7”H x 26.5”W x 17.7”D (1009.6 x 673.1 x 450.8 mm) |
| Weight | 110 lbs (49.9 kg) | 138 lbs (62.6 kg) |
| Warranty | 7/2(+3) | 5/3/2 |
| Cabinet Color | black, wood | black |
| Country | United States | United States |
| Measurement Source | Manufacturer | Data-bass |
| Drivers | 15” (381mm) driver | 18” (457mm) driver |
| Passive | - | Yes |
| Output SPL at 100 Hz | - | 135.1 dB |
| Output SPL at 125 Hz | - | 135.8 dB |
Related Speaker Comparisons
More top alternatives to JBL 4645C: