Short answer: the KEF R3. It ranks #15 of 222 bookshelf speakers by sound quality (rated 4.5/5) at $1,544.56 and is still sold new; the Buchardt S400 MKII ranks #111 (rated 3.8/5) and is discontinued, so it is only an option used. The Buchardt S400 MKII’s replacement, the Buchardt S400 MK3, is rated 4.0/5 at $2,300.
The KEF R3 is the more accurate choice. 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 measured preference score, a predictor of how neutral it sounds, is 6.20 against 5.38 for the Buchardt S400 MKII. 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.
Why pick the Buchardt S400 MKII: Bookshelf speakers with very flat sound, precise imaging and adjustable bass, now discontinued but worth buying used. The tradeoff: Sounds a bit bright and slightly boosted above about 7-8kHz on-axis, even with 30° of toe-out: benefits from about 1 inch of sidewall absorption at the first reflection points to tame it.
Buy the KEF R3. It is rated higher for sound quality; the Buchardt S400 MKII is no longer sold new.
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Specifications Side By Side
| KEF R3 | Buchardt S400 MKII | |
|---|---|---|
| Price | $1,544.56 per pair | $2400 per pair Discontinued |
| Ranked | #15 of 222 in Large Size Bookshelf Speakers | #111 of 222 in Large Size Bookshelf Speakers |
| Bass Extension (-3dB) | Approximately 58Hz (manufacturer specified; consistent with Erin’s measured roll-off) | 59Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-10dB) | 35.2Hz (measured, Audio Science Review) | 40Hz (measured, Erin’s Audio Corner) |
| Sensitivity | Approximately 86-87dB/2.83V/1m (measured, Erin’s Audio Corner) | 84.7dB (measured, Erin’s Audio Corner; 87dB manufacturer specified) |
| Impedance | 8 ohms nominal; suitable for Erin’s 4/8-ohm-rated amplifier | 4 ohms nominal, 3 ohms minimum (measured, Erin’s Audio Corner) |
| Drivers | 1” tweeter coaxial with 5” midrange; 6.5” woofer | 6.5” aluminum cone woofer, 1” soft dome tweeter |
| Dimensions | 16.6”H x 7.9”W x 13.2”D | 14.4”H x 7”W x 11”D (365.8 x 177.8 x 279.4 mm) |
| Woofer Cabinet | ported, rear Flexible Port | ported |
| Weight | 29.9 lbs (13.55 kg) each | 16.5 lbs (7.5 kg) each |
| Spinorama Preference Score | 6.2 (spinorama.org) | 5.38 |
| Spinorama Preference Score with Perfect Sub | 7.97 (spinorama.org) | 7.46 |
| DIY Kit | No | No |
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