Short answer: the KEF R3 if sound quality matters most, the Ascend Acoustics CBM-170 SE2 if price matters most. The KEF R3 ranks #15 of 222 bookshelf speakers, rated 4.5/5, at $1,544.56. The Ascend Acoustics CBM-170 SE2 ranks #113, rated 3.8/5, at $468, $1,076.56 cheaper.
The KEF R3 is the better-sounding, deeper-bass pick. A three way bookshelf speaker with KEF’s coaxial driver for stable imaging across seats and very low distortion, easy to run with a modest amp. Its bass reaches about 58Hz before falling 3dB, against 70Hz for the Ascend Acoustics CBM-170 SE2. Watch for: The low-frequency alignment rolls gradually rather than delivering high-output sub-bass; KEF specifies 58Hz +/-3dB and Erin’s high-level data supports using an 80Hz subwoofer crossover.
The case for the Ascend Acoustics CBM-170 SE2: Compact two-way bookshelf speakers with a SEAS tweeter, a very flat midrange and smooth sound that suits most rooms. The catch: A narrow dip in the on-axis and listening-window response appears in the 3-5kHz range (down to about -2.7dB), mirrored by a matching dip in the directivity index at the same frequencies: likely a brief widening of dispersion right at the tweeter/woofer crossover.
Buy the KEF R3 when sound quality outweighs the price for you, and the Ascend Acoustics CBM-170 SE2 when the price outweighs sound quality instead.
Still deciding? The full Passive Home rankings cover every ranked option.
A three way bookshelf speaker with KEF’s coaxial driver for stable imaging across seats and very low distortion, easy to run with a modest amp.
Compact two-way bookshelf speakers with a SEAS tweeter, a very flat midrange and smooth sound that suits most rooms.
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.
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Specifications Side By Side
| KEF R3 | Ascend Acoustics CBM-170 SE2 | |
|---|---|---|
| Price | $1,544.56 per pair | $468 per pair |
| Ranked | #15 of 222 in Large Size Bookshelf Speakers | #113 of 222 in Large Size Bookshelf Speakers |
| Bass Extension (-3dB) | Approximately 58Hz (manufacturer specified; consistent with Erin’s measured roll-off) | 70Hz (measured, manufacturer spinorama data) |
| Bass Extension (-10dB) | 35.2Hz (measured, Audio Science Review) | 50Hz (measured, manufacturer spinorama data) |
| Sensitivity | Approximately 86-87dB/2.83V/1m (measured, Erin’s Audio Corner) | 86.8dB (2.83V/1m, measured, manufacturer spinorama data; 87dB manufacturer specified) |
| Impedance | 8 ohms nominal; suitable for Erin’s 4/8-ohm-rated amplifier | 8 ohms |
| Drivers | 1” tweeter coaxial with 5” midrange; 6.5” woofer | 27mm custom SEAS soft dome tweeter, 6.5” proprietary composite polygel cone woofer |
| Dimensions | 16.6”H x 7.9”W x 13.2”D | 12H x 9W x 9.5D in |
| Woofer Cabinet | ported, rear Flexible Port | ported, rear |
| Weight | 29.9 lbs (13.55 kg) each | 15 lbs (6.8 kg) each |
| Spinorama Preference Score | 6.2 (spinorama.org) | 6.30 |
| Spinorama Preference Score with Perfect Sub | 7.97 (spinorama.org) | 8.66 |
| DIY Kit | No | No |
| Power Handling | - | 200W continuous, 400W peak |
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