The Buchardt S400 MKII ranks #55 out of 105 total Large Size Bookshelf Speakers for sound quality. See Top Recommended Speakers By Attribute for all the top speaker suggestions.
Brand: Buchardt
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#55 Buchardt S400 MKII: $2400 Buchardtaudio eBay
Pros: Two-way design with a 3/4” tweeter on a well-implemented aluminum waveguide (compression-driver style, letting the small tweeter cross unusually low at 1800Hz), a 6” SB Acoustics-style mid-woofer, and a tunable 5x8” passive radiator adjustable via rear weights. Exceptionally flat on-axis linearity, within about ±2dB from 80Hz to 16kHz. Wide horizontal radiation for a waveguided design (about ±45-50°), notably broader than a comparable narrow-waveguide rival like the Klipsch Sevens (~±30°). Well-focused, precise imaging, aided by tight pair matching between the two speakers. Takes very well to EQ correction, letting listeners easily dial in the top end or add midrange fullness to taste. Bass extension reaches a genuine 50Hz in-room from a mellow, well-tuned rolloff rather than an artificially boosted one.
Cons: 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. A mild dullness noted especially on male vocals, alongside a small dip around 300-600Hz. Vertical positioning is critical and unusually “temperamental” - sitting even slightly toward the tweeter line causes a suckout, while sitting above it adds too much energy; not well suited to multi-height home theater seating. Distortion is fine at 86dB but runs into real issues by 96dB - not a high-output speaker. Some compression-related enhancement appears around 1.2kHz (crossover-region interaction), and the tweeter shows clear compression at 102dB. The woofer can bottom out at extreme low-frequency content played very loud; crossing to a subwoofer below 60Hz caused output problems at high volume, while 80-100Hz worked well. A subwoofer isn’t strictly required to protect the speaker at moderate listening levels (80-85dB at 3 meters), but is still recommended for genuine low-octave extension.
How it compares: Just above it: Monolith Encore C6 - $2150 cheaper, 1.6Hz higher bass extension (-3dB). Just below it: Infinity Reference R162 - $1900 cheaper, 2.3Hz higher bass extension (-3dB).
| Bass Extension (-10dB) | 40Hz (measured, Erin's Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 59Hz (measured, Erin's Audio Corner) |
| Dimensions | 14.4"H x 7"W x 11"D (365.8 x 177.8 x 279.4 mm) |
| Drivers | 6.5" aluminum cone woofer, 1" soft dome tweeter |
| Impedance | 4 ohms nominal, 3 ohms minimum (measured, Erin's Audio Corner) |
| Sensitivity | 84.7dB (measured, Erin's Audio Corner; 87dB manufacturer specified) |
| Weight | 16.5 lbs / 7.5 kg each |
| Woofer Cabinet | ported |
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