Short answer: the Radiant Acoustics Clarity 66 if sound quality matters most, the JBL HDI-3600 if price matters most. The Radiant Acoustics Clarity 66 ranks #11 of 228 floorstanding speakers, rated 4.6/5, at $7,998. The JBL HDI-3600 ranks #63, rated 4.3/5, at $3,800, $4,198 cheaper.
The Radiant Acoustics Clarity 66 is the more accurate, deeper-bass pick. 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 4.64 for the JBL HDI-3600. Its bass reaches about 32.2Hz before falling 3dB, against 78Hz for the JBL HDI-3600. The tradeoff: Vertical directivity is narrow and horizontal coverage is uneven, so listening height and placement affect tonal balance.
The case for the JBL HDI-3600: Floorstanding speakers with a horn tweeter, triple woofers, high sensitivity and very low distortion, made for loud music and movies. Watch for: A wide shelving-down above 2kHz affects the in-room response, and vertical dispersion is a bigger issue than horizontal: the reviewer noted the dip is wider here than on the smaller JBL HDI-1600, making it more audible.
Buy the Radiant Acoustics Clarity 66 when sound quality outweighs the price for you, and the JBL HDI-3600 when the price outweighs sound quality instead.
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.
Floorstanding speakers with a horn tweeter, triple woofers, high sensitivity and very low distortion, made for loud music and movies.
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Specifications Side By Side
| Radiant Acoustics Clarity 66 | JBL HDI-3600 | |
|---|---|---|
| Price | $7,998 per pair | $3800 per pair |
| Ranked | #11 of 228 in Large Size Floorstanding Speakers | #63 of 228 in Large Size Floorstanding Speakers |
| Bass Extension (-3dB) | 32.2Hz (measured, Audio Science Review) | 78Hz - the on-axis curve also shows an unusual step/dip around 40-55Hz that may be a near-field-scan artifact for this tower (measured, Audio Science Review) |
| Bass Extension (-10dB) | 24.4Hz (measured, Audio Science Review) | 62Hz - the on-axis curve also shows an unusual step/dip around 40-55Hz that may be a near-field-scan artifact for this tower (measured, Audio Science Review) |
| Sensitivity | 85.9dB (2.83V/1m, measured, Audio Science Review; 86dB manufacturer specified) | 89.5dB (2.83V/1m, measured, Audio Science Review) |
| Drivers | Custom waveguide-loaded tweeter with beam-expansion fins, 2x 6.5” Purifi USHINDI aluminum-cone woofers | 2410H-2 1” compression driver, 3x 6.5” Advanced Aluminum Matrix woofers |
| Dimensions | 40.4”H x 8.7”W x 14”D (1025 x 222 x 355 mm) | 40.5”H x 10.2”W x 13.5”D (1029 x 260 x 343 mm) |
| Weight | 101.4 lbs (46 kg) each | 61.7 lbs (28 kg) each |
| Impedance | 4 ohms nominal | 4 ohms nominal |
| Crossover Frequency | 2.4kHz | - |
| Woofer Cabinet | ported, large rear port | ported, dual rear-firing |
| Spinorama Preference Score | 6.01 | 4.64 (spinorama.org) |
| Spinorama Preference Score with Perfect Sub | 7.03 | 6.95 (spinorama.org) |
| DIY Kit | No | No |
| Frequency Response | - | 38Hz - 30kHz (+/-3dB) (Manufacturer specified) |
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