Short answer: the Radiant Acoustics Clarity 66 if sound quality matters most, the ELAC Debut 3.0 DF63 if price matters most. The Radiant Acoustics Clarity 66 ranks #5 of 71 floorstanding speakers at $7998. The ELAC Debut 3.0 DF63 ranks #35 at $649, $7349 cheaper.
What the Radiant Acoustics Clarity 66 offers: ASR’s revised Spinorama measurement shows bass reaching 32.2Hz at -3dB and 27.8Hz at -6dB, giving substantial low-end weight without a subwoofer. The response spans 2.3dB from 300Hz to 5kHz, with preference scores of 5.10 standalone and 6.12 with an ideal subwoofer. The review’s exceptionally low bass distortion at ordinary levels complements that extension, while dual 6.5-inch Purifi woofers provide a strong foundation for full-range listening. Watch for: Vertical directivity is narrow and horizontal coverage is uneven, so listening height and placement affect tonal balance. Treble resonances and response irregularities keep it from reference-level neutrality. Spinorama’s modeled EQ improves the scores to 6.09 standalone and 6.99 with an ideal subwoofer, but those are corrected results, not stock performance. Measured sensitivity is 85.9dB at 2.83V/1m with a nominal 4-ohm load; use an amplifier comfortable driving 4 ohms. Distortion rises at very high playback levels.
What the ELAC Debut 3.0 DF63 offers: Three-driver floorstanding layout: two 6” dedicated midbase drivers plus a separate 6” mid-range driver (confirmed by measuring different driver impedance/inductance) and a 1” dome tweeter, each woofer given its own stuffed chamber inside the cabinet. The dedicated midrange driver keeps distortion low even at higher output, avoiding the intermodulation grain typical of two-way bookshelf designs. The waveguide keeps high-frequency directivity well controlled, and overall horizontal directivity is good up to about 2kHz. Harmonic distortion looks good at both 86dB and 96dB, and multitone distortion stays below the reviewer’s 3% threshold. A shallow bass rolloff (F3 71Hz, F10 29Hz) lets it extend fairly low without a hard cutoff. Preferred by the reviewer over the similarly-priced Polk R500 (too much high-frequency narrowing, less neutral) and considered ahead of the Polk R700 as well. Watch for: A genuine measured resonance around 200-300Hz (visible in frequency response, impedance, and group delay) causes an audible “droning” coloration on female vocals. A mild peak around 10kHz makes shakers and similar high-frequency percussion jump too far forward in the mix; needed about 2dB of EQ to tame in testing. A dip in the 1-3kHz range gives the speaker a warm, slightly veiled character - the reviewer suspects the tweeter crossover point (around 2-3kHz) is set a bit high and could be lowered to fill this in. Directivity shows a noticeable handoff mismatch around 2.5kHz where the midrange driver hands off to the tweeter, though it’s minor at the -6dB point. Vertical directivity is narrower than horizontal, so listeners need to stay close to the tweeter axis. Low EPDR (about 1.5 ohms minimum) means a Class AB amplifier should be well-ventilated. Best positioned pointed directly at the listener and closer to the front wall - toeing it out into the room causes too much high-frequency rolloff.
Buy the Radiant Acoustics Clarity 66 if sound quality is the priority over the price, or the ELAC Debut 3.0 DF63 if the price is the priority over sound quality.
Still deciding? The full Passive Home rankings cover every ranked option.
Specifications Side By Side
| Radiant Acoustics Clarity 66 | ELAC Debut 3.0 DF63 | |
|---|---|---|
| Price | $7,998 per pair | $649.00 per pair |
| Ranked | #5 of 71 in Large Size Floorstanding Speakers | #35 of 71 in Large Size Floorstanding Speakers |
| Bass Extension (-3dB) | 32.2Hz (measured, Audio Science Review) | 71Hz (measured, Erin's Audio Corner) |
| Bass Extension (-10dB) | 24.4Hz (measured, Audio Science Review) | 29Hz (measured, Erin's Audio Corner) |
| Sensitivity | 85.9dB (2.83V/1m, measured, Audio Science Review; 86dB manufacturer specified) | 86.6dB (measured, Erin's Audio Corner) |
| Drivers | Custom waveguide-loaded tweeter with beam-expansion fins, 2x 6.5" Purifi USHINDI aluminum-cone woofers | Two 6.5" Aramid Fiber woofer, 6.5" Aramid Fiber midrange, 1" Aluminum Dome tweeter |
| Dimensions | 40.4"H x 8.7"W x 14"D (1025 x 222 x 355 mm) | 43.1"H x 7.7"W x 10.6"D (1094.7 x 195.6 x 269.2 mm) |
| Weight | 101.4 lbs (46 kg) each | 58.2 lbs (26.4 kg) each |
| Impedance | 4 ohms nominal | 6 ohms nominal (3.4 ohms minimum, measured, Erin's Audio Corner) |
| Crossover Frequency | 2.4kHz | - |
| Woofer Cabinet | ported, large rear port | ported, rear |
| Spinorama Preference Score | 5.10 | 4.93 |
| Spinorama Preference Score with Perfect Sub | 6.12 | 6.42 |
Related Speaker Comparisons
How Radiant Acoustics Clarity 66 compares with other leading options:
- Radiant Acoustics Clarity 66 vs KEF Blade Two Meta
- Radiant Acoustics Clarity 66 vs MoFi SourcePoint V10 Master Edition
- Radiant Acoustics Clarity 66 vs MoFi SourcePoint 888
- Radiant Acoustics Clarity 66 vs Ascend Acoustics ELX Ribbon Tower
- Radiant Acoustics Clarity 66 vs Revel F328Be
Prices on this page were last checked September 16, 2026 at 12:41 AM 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.
As an eBay Partner, we may be compensated if you make a purchase.
The Two Speakers In Full
Radiant Acoustics Clarity 66: $7,998 per pair Radiant Acoustics eBay
Pros: ASR’s revised Spinorama measurement shows bass reaching 32.2Hz at -3dB and 27.8Hz at -6dB, giving substantial low-end weight without a subwoofer. The response spans 2.3dB from 300Hz to 5kHz, with preference scores of 5.10 standalone and 6.12 with an ideal subwoofer. The review’s exceptionally low bass distortion at ordinary levels complements that extension, while dual 6.5-inch Purifi woofers provide a strong foundation for full-range listening. Measured bass extension of 32.2Hz (-3dB), with a measured sensitivity of 85.9dB.
Cons: Vertical directivity is narrow and horizontal coverage is uneven, so listening height and placement affect tonal balance. Treble resonances and response irregularities keep it from reference-level neutrality. Spinorama’s modeled EQ improves the scores to 6.09 standalone and 6.99 with an ideal subwoofer, but those are corrected results, not stock performance. Measured sensitivity is 85.9dB at 2.83V/1m with a nominal 4-ohm load; use an amplifier comfortable driving 4 ohms. Distortion rises at very high playback levels.
Full Radiant Acoustics Clarity 66 review and specifications →
| Bass Extension (-10dB) | 24.4Hz (measured, Audio Science Review) |
|---|---|
| Bass Extension (-3dB) | 32.2Hz (measured, Audio Science Review) |
| Crossover Frequency | 2.4kHz |
| Dimensions | 40.4"H x 8.7"W x 14"D (1025 x 222 x 355 mm) |
| Drivers | Custom waveguide-loaded tweeter with beam-expansion fins, 2x 6.5" Purifi USHINDI aluminum-cone woofers |
| Impedance | 4 ohms nominal |
| Sensitivity | 85.9dB (2.83V/1m, measured, Audio Science Review; 86dB manufacturer specified) |
| Spinorama Preference Score | 5.10 |
| Spinorama Preference Score with Perfect Sub | 6.12 |
| Weight | 101.4 lbs (46 kg) each |
| Woofer Cabinet | ported, large rear port |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Radiant Acoustics Clarity 66 vs Ascend Acoustics ELX Ribbon Tower
- Radiant Acoustics Clarity 66 vs MoFi SourcePoint 888
- Radiant Acoustics Clarity 66 vs MoFi SourcePoint V10 Master Edition
- Radiant Acoustics Clarity 66 vs KEF Blade Two Meta
- Radiant Acoustics Clarity 66 vs Revel F328Be
- Radiant Acoustics Clarity 66 vs Revel F226Be
- Radiant Acoustics Clarity 66 vs JBL 4367
- Radiant Acoustics Clarity 66 vs Revel F228Be
- See all 23 comparisons
ELAC Debut 3.0 DF63: $649.00 per pair Amazon eBay
Pros: Three-driver floorstanding layout: two 6” dedicated midbase drivers plus a separate 6” mid-range driver (confirmed by measuring different driver impedance/inductance) and a 1” dome tweeter, each woofer given its own stuffed chamber inside the cabinet. The dedicated midrange driver keeps distortion low even at higher output, avoiding the intermodulation grain typical of two-way bookshelf designs. The waveguide keeps high-frequency directivity well controlled, and overall horizontal directivity is good up to about 2kHz. Harmonic distortion looks good at both 86dB and 96dB, and multitone distortion stays below the reviewer’s 3% threshold. A shallow bass rolloff (F3 71Hz, F10 29Hz) lets it extend fairly low without a hard cutoff. Preferred by the reviewer over the similarly-priced Polk R500 (too much high-frequency narrowing, less neutral) and considered ahead of the Polk R700 as well. Measured bass extension of 71Hz (-3dB), with a measured sensitivity of 86.6dB.
Cons: A genuine measured resonance around 200-300Hz (visible in frequency response, impedance, and group delay) causes an audible “droning” coloration on female vocals. A mild peak around 10kHz makes shakers and similar high-frequency percussion jump too far forward in the mix; needed about 2dB of EQ to tame in testing. A dip in the 1-3kHz range gives the speaker a warm, slightly veiled character - the reviewer suspects the tweeter crossover point (around 2-3kHz) is set a bit high and could be lowered to fill this in. Directivity shows a noticeable handoff mismatch around 2.5kHz where the midrange driver hands off to the tweeter, though it’s minor at the -6dB point. Vertical directivity is narrower than horizontal, so listeners need to stay close to the tweeter axis. Low EPDR (about 1.5 ohms minimum) means a Class AB amplifier should be well-ventilated. Best positioned pointed directly at the listener and closer to the front wall - toeing it out into the room causes too much high-frequency rolloff.
Full ELAC Debut 3.0 DF63 review and specifications →
| Bass Extension (-10dB) | 29Hz (measured, Erin's Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 71Hz (measured, Erin's Audio Corner) |
| Dimensions | 43.1"H x 7.7"W x 10.6"D (1094.7 x 195.6 x 269.2 mm) |
| Drivers | Two 6.5" Aramid Fiber woofer, 6.5" Aramid Fiber midrange, 1" Aluminum Dome tweeter |
| Impedance | 6 ohms nominal (3.4 ohms minimum, measured, Erin's Audio Corner) |
| Sensitivity | 86.6dB (measured, Erin's Audio Corner) |
| Spinorama Preference Score | 4.93 |
| Spinorama Preference Score with Perfect Sub | 6.42 |
| Weight | 58.2 lbs (26.4 kg) each |
| Woofer Cabinet | ported, rear |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- ELAC Debut 3.0 DF63 vs Polk Reserve R500
- ELAC Debut 3.0 DF63 vs PSB Imagine T65
- ELAC Debut 3.0 DF63 vs Linkwitz Lab LXmini
- ELAC Debut 3.0 DF63 vs Q Acoustics 5040
- ELAC Debut 3.0 DF63 vs Polk Audio Reserve R700
- ELAC Debut 3.0 DF63 vs Definitive Technology BP-9020
- ELAC Debut 3.0 DF63 vs Infinity Primus 360
- ELAC Debut 3.0 DF63 vs Emotiva Airmotiv T2+
- See all 41 comparisons