Short answer: the Klipsch Flexus Sub 100. It ranks #22 of 73 subwoofers by sound quality (rated 3.4/5) at $349 and is still sold new; the Klipsch HD Theater 600 ranks #35 (rated 3.3/5) and is discontinued, so it is only an option used.
What the Klipsch Flexus Sub 100 does well: A compact sealed 10 inch subwoofer made to add bass to a Klipsch Flexus soundbar in a small room. Watch for: Only works with Klipsch Flexus soundbars, not as a standalone LFE sub.
Why pick the Klipsch HD Theater 600: A discontinued compact ported 8 inch subwoofer that adds midbass support to a small home theater system. The catch: Without a published 20 Hz result, deep-bass capability is less certain than the midbass figure.
Buy the Klipsch Flexus Sub 100. It is rated higher for sound quality and still sold new, while the Klipsch HD Theater 600 is discontinued.
Still deciding? The full Subwoofers rankings cover every ranked option.
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Specifications Side By Side
| Klipsch Flexus Sub 100 | Klipsch HD Theater 600 | |
|---|---|---|
| Price | $349.00 | $399 Discontinued |
| Ranked | #22 of 73 in Small Home Subwoofers (Under 30 lbs) | #35 of 73 in Small Home Subwoofers (Under 30 lbs) |
| Country | United States | United States |
| Enclosure | sealed | ported, rear |
| Output SPL at 20 Hz | 90.2 dB | - |
| Output SPL at 25 Hz | 96.7 dB | 87.1 dB |
| Output SPL at 31.5 Hz | 101.2 dB | 98.4 dB |
| Output SPL at 40 Hz | 105.9 dB | 104.9 dB |
| Output SPL at 50 Hz | 109.0 dB | 107.6 dB |
| Output SPL at 63 Hz | 112.4 dB | 112.1 dB |
| CEA-2010-A Average (40-80Hz) | 109.1 dB (avg of 3/4 bands) | 108.2 dB (avg of 3/4 bands) |
| Dimensions | 13.4”H x 13.2”W x 13.7”D (339.9 x 335.0 x 349.2 mm) | 13.9”H x 12.5”W x 12.5”D (353.1 x 317.5 x 317.5 mm) |
| Weight | 20.7 lbs (9.4 kg) | 17 lbs (7.7 kg) |
| Warranty | 2/5 | - |
| Measurement Source | Brent Butterworth | Brent Butterworth |
| Drivers | 10” (254mm) driver | 8” (203mm) driver |
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