Short answer: the Buchardt S400 MK3 for better sound quality, the Klipsch RP-600M II for the lower price. The Buchardt S400 MK3 ranks #59 of 141 bookshelf speakers, rated 4.0/5, at $2,300. The Klipsch RP-600M II ranks #79, rated 3.7/5, at $449.99, $1,850.01 cheaper.
What the Buchardt S400 MK3 does well: A ground-up redesign of the S400 with an 18 percent larger cabinet and a 7.5” SB Acoustics Satori Papyrus paper cone woofer, which Buchardt says has 65.5 percent more displacement than the MKII’s 6” driver. The tradeoff: No independent measurements have been published yet.
The case for the Klipsch RP-600M II: Redesigned waveguide extends flush to the baffle edge, reducing diffraction compared to the original RP-600M. The tradeoff: On-axis, the treble runs notably hot (even hotter than the original RP-600M in some respects) and needs about 20° of toe-out or the grille installed to sound balanced.
Buy the Buchardt S400 MK3 when sound quality outweighs the price for you, and the Klipsch RP-600M II when the price outweighs sound quality instead.
Want more options? Browse the full Passive Home rankings.
Specifications Side By Side
| Buchardt S400 MK3 | Klipsch RP-600M II | |
|---|---|---|
| Price | $2,300 per pair | $449.99 per pair |
| Ranked | #59 of 141 in Large Size Bookshelf Speakers | #79 of 141 in Large Size Bookshelf Speakers |
| Crossover Frequency | 2.2kHz (first order) | - |
| Dimensions | 15.4”H x 7.8”W x 11”D (392 x 198 x 280 mm) | 15.7”H x 8”W x 12.5”D (398.8 x 203.2 x 317.5 mm) |
| DIY Kit | No | No |
| Drivers | 1” aluminum dome tweeter in waveguide, 7.5” Satori Papyrus paper cone woofer | 6.5” Cerametallic cone woofer, 1” titanium LTS vented tweeter with Tractrix horn |
| Frequency Response | 33Hz - 20kHz (in-room, manufacturer specified) | - |
| Impedance | 4 ohms | 8 ohms nominal (3.5 ohms minimum above 80Hz, measured by Erin’s Audio Corner) |
| Sensitivity | 87dB anechoic, 90dB in-room (manufacturer specified) | 86dB (measured, Erin’s Audio Corner) |
| Weight | 18.7 lbs (8.5 kg) each | 13 lbs (5.9 kg) each |
| Woofer Cabinet | ported, rear | ported |
| Bass Extension (-10dB) | - | 41Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-3dB) | - | 70Hz (measured, Erin’s Audio Corner) |
| Spinorama Preference Score | - | 5.64 |
| Spinorama Preference Score with Perfect Sub | - | 7.77 |
Related Speaker Comparisons
More worthwhile head-to-heads for Buchardt S400 MK3:
- KEF R3 Meta vs Buchardt S400 MK3
- KEF Q Concerto Meta vs Buchardt S400 MK3
- KEF R3 vs Buchardt S400 MK3
- Wharfedale Super Linton vs Buchardt S400 MK3
- Wharfedale Linton 85 vs Buchardt S400 MK3
Prices on this page were last checked October 4, 2026 at 9:58 PM 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.
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The Two Speakers In Full
Buchardt S400 MK3: $2,300 per pair Estimated Buchardt Audio eBay
Older models: the Buchardt Audio S400 (ranked higher, rated 4.4/5) and the Buchardt S400 MKII (ranked lower, rated 3.8/5).
Pros: A ground-up redesign of the S400 with an 18 percent larger cabinet and a 7.5” SB Acoustics Satori Papyrus paper cone woofer, which Buchardt says has 65.5 percent more displacement than the MKII’s 6” driver. A custom 1” aluminum dome tweeter sits in a new waveguide, crossed at 2.2kHz with a first order Jantzen crossover. Buchardt rates in-room bass extension to 33Hz and anechoic sensitivity at 87dB, and includes foam port plugs to trim bass near a wall. Sold direct with free worldwide shipping, duties included, and a 10 year warranty for the first owner.
Cons: No independent measurements have been published yet. The S400 MKII measured very well, but the MK3 shares only its binding posts, so that result can’t be carried over and its linearity, directivity and real bass extension are unknown. The 33Hz figure is an in-room number, not an anechoic one. The MKII’s adjustable passive radiator is gone in favor of a rear port that wants at least 5cm from the wall. A 4 ohm load means it needs an amplifier comfortable driving 4 ohms, and it is sold only direct from Buchardt.
Full Buchardt S400 MK3 review and specifications →
| Crossover Frequency | 2.2kHz (first order) |
|---|---|
| DIY Kit | No |
| Dimensions | 15.4”H x 7.8”W x 11”D (392 x 198 x 280 mm) |
| Drivers | 1” aluminum dome tweeter in waveguide, 7.5” Satori Papyrus paper cone woofer |
| Frequency Response | 33Hz - 20kHz (in-room, manufacturer specified) |
| Impedance | 4 ohms |
| Sensitivity | 87dB anechoic, 90dB in-room (manufacturer specified) |
| Weight | 18.7 lbs (8.5 kg) each |
| Woofer Cabinet | ported, rear |
- Links
- Reviews, Comparisons and Sound Samples
- No independent measurement review is linked for this model; it is ranked from hands-on listening and comparison against similarly priced speakers.
- Head-to-Head Comparisons
- Buchardt S400 MK3 vs ELAC DBR62
- Buchardt S400 MK3 vs Buchardt S400 MKII
- Buchardt S400 MK3 vs ELAC Debut 3.0 DB63
- Buchardt S400 MK3 vs Wharfedale Linton 85
- Buchardt S400 MK3 vs Wharfedale Super Linton
- Buchardt S400 MK3 vs KEF Q3 Meta
- Buchardt S400 MK3 vs KEF R3
- Buchardt S400 MK3 vs KEF Q Concerto Meta
- See all 10 comparisons
Klipsch RP-600M II: $449.99 per pair Amazon eBay
Older model: the Klipsch RP-600M (ranked lower, rated 2.9/5).
Smaller model: the Klipsch RP-500M II (rated 4/5).
Larger models: the Klipsch RP-5000F II (rated 4/5), the Klipsch RP-6000F II (rated 3.9/5) and the Klipsch RP-8000F II (rated 3.9/5).
Pros: Redesigned waveguide extends flush to the baffle edge, reducing diffraction compared to the original RP-600M. Roughly 10-20° wider horizontal radiation than the original, giving more soundstage envelopment while retaining precise imaging. A major step up in overall tonal neutrality compared to the original RP-600M, largely eliminating that model’s midrange resonance issues. Unusually, sounds better with the grille on: the grille smooths out the elevated treble rather than degrading the sound, a rare trait among speakers the reviewer has tested. More refined back-panel hardware, including anodized binding posts and jumper cables for optional bi-amping. Responds well to EQ correction (verified using measurement software and a miniDSP), letting the on-axis response be made genuinely linear. Measured bass extension of 70Hz (-3dB), with a measured sensitivity of 86dB.
Cons: On-axis, the treble runs notably hot (even hotter than the original RP-600M in some respects) and needs about 20° of toe-out or the grille installed to sound balanced. Horizontal dispersion is very slightly less linear across angles than the original RP-600M, a minor trade-off for the wider overall radiation pattern. Klipsch’s marketed sensitivity (about 94.5dB) is, like the original, a half-space rating roughly 9dB above the anechoic reality (closer to 85-86dB). In-room bass rolls off around 60Hz in practice, and a 120Hz boost paired with a midrange scoop gives kick drums their “tambour” without real low-end weight: a subwoofer is still recommended. Vertical listening tolerance is limited to about ±10° from the tweeter axis. Toeing the speaker out for better on-axis tonality (rather than using the grille) introduces slightly more diffuse imaging from added sidewall reflections.
Full Klipsch RP-600M II review and specifications →
| Bass Extension (-10dB) | 41Hz (measured, Erin’s Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 70Hz (measured, Erin’s Audio Corner) |
| DIY Kit | No |
| Dimensions | 15.7”H x 8”W x 12.5”D (398.8 x 203.2 x 317.5 mm) |
| Drivers | 6.5” Cerametallic cone woofer, 1” titanium LTS vented tweeter with Tractrix horn |
| Impedance | 8 ohms nominal (3.5 ohms minimum above 80Hz, measured by Erin’s Audio Corner) |
| Sensitivity | 86dB (measured, Erin’s Audio Corner) |
| Spinorama Preference Score | 5.64 |
| Spinorama Preference Score with Perfect Sub | 7.77 |
| Weight | 13 lbs (5.9 kg) each |
| Woofer Cabinet | ported |
- Links
- Reviews, Comparisons and Sound Samples
- Erin’s Audio Corner: The Truth about Klipsch’s “NEW” Sound. RP-600M Update. More from Erin’s Audio Corner →
- Erin’s Audio Corner Website Klipsch RP-600M II
- GR-Research: We Bought The "NEW" RP-600M II Is KLIPSCH Listening?! More from GR-Research →
- Erin’s Audio Corner: 5 AWESOME SPEAKERS Under $1000 You Won’t Regret
- Erin’s Audio Corner Measurements (spinorama.org)
- Erin’s Audio Corner: KEF Q1 Meta vs Emotiva vs Klipsch | The Real Differences
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