Short answer: the AsciLab C6B. It ranks #6 of 222 bookshelf speakers by sound quality, rated 4.7/5, at $1,145. The Polk Reserve R100 ranks #160, rated 3.4/5, at $559, $586 cheaper, a saving that is not big enough to make up the sound-quality gap.
The AsciLab C6B is the more accurate, deeper-bass choice. Two-way design pairing a 1” aluminum ceramic dome tweeter on a large waveguide with a 6” aluminum ceramic cone woofer, crossed over at 1.1kHz, plus a rear passive radiator. Its measured preference score, a predictor of how neutral it sounds, is 6.33 against 5.46 for the Polk Reserve R100. Its bass reaches about 54Hz before falling 3dB, against 68Hz for the Polk Reserve R100. The tradeoff: Bass rolls off around 50Hz in-room (F3 54Hz, F10 35Hz), so a subwoofer is needed for real extension below that.
What the Polk Reserve R100 does well: Compact cabinet, unusually useful bass for its size and well-controlled woofer breakup. The catch: Erin measured only about 85dB sensitivity and the impedance reaches 3.6 ohms, so it is neither efficient nor an entirely benign AVR load.
Buy the AsciLab C6B. It is rated higher for sound quality, and the $586 you would save on the Polk Reserve R100 does not close the gap.
Still deciding? The full Passive Home rankings cover every ranked option.
Two-way design pairing a 1” aluminum ceramic dome tweeter on a large waveguide with a 6” aluminum ceramic cone woofer, crossed over at 1.1kHz, plus a rear passive radiator.
Ascilab $1145 eBay
Compact cabinet, unusually useful bass for its size and well-controlled woofer breakup.
Amazon $559.00 Polk Audio $649 eBayPrices on this page were last checked October 16, 2026 at 5:46 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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Specifications Side By Side
| AsciLab C6B | Polk Reserve R100 | |
|---|---|---|
| Price | $1145 per pair | $559.00 per pair |
| Ranked | #6 of 222 in Large Size Bookshelf Speakers | #160 of 222 in Large Size Bookshelf Speakers |
| Bass Extension (-10dB) | 35Hz (measured, Erin’s Audio Corner) | 49Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-3dB) | 54Hz (measured, Erin’s Audio Corner) | 68Hz (measured, Erin’s Audio Corner) |
| Dimensions | 15.7”H x 8”W x 10.4”D (398.8 x 203.2 x 264.2 mm) | 12.8”H x 6.5”W x 10.2”D |
| Impedance | 4 ohms nominal, 2.6 ohms minimum (measured, Erin’s Audio Corner) | 3.6 ohms minimum (measured, Erin’s Audio Corner) |
| Sensitivity | 85.6dB (measured, Erin’s Audio Corner) | 85dB/2.83V/1m (measured, Erin’s Audio Corner) |
| Drivers | 6” Aluminium Ceramic Cone with cast Aluminium Chassis woofer, 1” Aluminium Ceramic Dome tweeter | 1” Pinnacle ring-radiator tweeter; 5.25” Turbine Cone midwoofer |
| Weight | 18.5 lbs (8.4 kg) each | 12.1 lbs (5.5 kg) each |
| Woofer Cabinet | passive radiator | ported, rear X-Port |
| Spinorama Preference Score | 6.33 | 5.46 |
| Spinorama Preference Score with Perfect Sub | 8.28 | 7.93 |
| DIY Kit | No | No |
Frequency Response Compared
Both speakers’ spinorama measurements, overlaid. A flatter line is more neutral: peaks sound forward or harsh, dips sound recessed. Each curve is shifted so its average from 300 Hz to 3 kHz sits at 0 dB, so loudness differences between the two are removed and only the shape is compared.
Measurement data: AsciLab C6B (measured by Erin’s Audio Corner) and Polk Reserve R100 (measured by Erin’s Audio Corner), via spinorama.org.
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