Short answer: the Radiant Acoustics Clarity 66. It ranks #11 of 228 floorstanding speakers by sound quality, rated 4.6/5, at $7,998. The Q Acoustics 5040 ranks #113, rated 4.1/5, at $3,998, $4,000 cheaper, which does not close the gap in sound quality.
The Radiant Acoustics Clarity 66 is the more accurate, deeper-bass choice. Highly accurate floorstanding speakers with Purifi woofers and bass deep enough to skip a subwoofer. Its measured preference score, a predictor of how neutral it sounds, is 6.01 against 3.80 for the Q Acoustics 5040. Its bass reaches about 32.2Hz before falling 3dB, against 70Hz for the Q Acoustics 5040. The tradeoff: Vertical directivity is narrow and horizontal coverage is uneven, so listening height and placement affect tonal balance.
The case for the Q Acoustics 5040: Well-built floorstanding speakers that are easy to drive, playing loud on modest amplifiers with a smooth, well-integrated midrange. The tradeoff: Free-field frequency response exhibits a noticeable mid-bass scoop around 200Hz (~6dB lower than mean SPL), causing an F3 of 70Hz (F10 of 39Hz) in open space and requiring boundary placement (11-22 inches from front wall) to reinforce upper bass output.
Buy the Radiant Acoustics Clarity 66. It is rated higher for sound quality, and saving $4,000 with the Q Acoustics 5040 does not make up for the sound-quality gap.
Still deciding? The full Passive Home rankings cover every ranked option.
Highly accurate floorstanding speakers with Purifi woofers and bass deep enough to skip a subwoofer.
Well-built floorstanding speakers that are easy to drive, playing loud on modest amplifiers with a smooth, well-integrated midrange.
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Specifications Side By Side
| Radiant Acoustics Clarity 66 | Q Acoustics 5040 | |
|---|---|---|
| Price | $7,998 per pair | $3,998 per pair |
| Ranked | #11 of 228 in Large Size Floorstanding Speakers | #113 of 228 in Large Size Floorstanding Speakers |
| Bass Extension (-3dB) | 32.2Hz (measured, Audio Science Review) | 70Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-10dB) | 24.4Hz (measured, Audio Science Review) | 39Hz (measured, Erin’s Audio Corner) |
| Sensitivity | 85.9dB (2.83V/1m, measured, Audio Science Review; 86dB manufacturer specified) | 91.5dB (measured average, Erin’s Audio Corner) |
| Drivers | Custom waveguide-loaded tweeter with beam-expansion fins, 2x 6.5” Purifi USHINDI aluminum-cone woofers | 0.88 in. decoupled dome tweeter, twin 5.0 in. C3 Continuous Curved Cone woofers |
| Dimensions | 40.4”H x 8.7”W x 14”D (1025 x 222 x 355 mm) | 38.1”H x 11.5”W x 14.2”D (967 x 293 x 361 mm) |
| Weight | 101.4 lbs (46 kg) each | 39.7 lbs (18.0 kg) each |
| Impedance | 4 ohms nominal | 6 ohms nominal (3.0 ohms minimum, measured by Erin’s Audio Corner) |
| Crossover Frequency | 2.4kHz | - |
| Woofer Cabinet | ported, large rear port | ported, rear |
| Spinorama Preference Score | 6.01 | 3.80 |
| Spinorama Preference Score with Perfect Sub | 7.03 | 6.41 |
| DIY Kit | No | No |
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