Short answer: both are discontinued, so this only matters if you are buying used. Used, the Buchardt S400 MKII is the better pick: it ranks #111 of 222 bookshelf speakers by sound quality (rated 3.8/5), against #186 (rated 3.0/5) for the Pylon Jasper Monitor 18. If you want one new, the Buchardt S400 MK3 replaces the Buchardt S400 MKII and is rated 4.0/5 at $2,300.
The Buchardt S400 MKII is the more accurate option. Bookshelf speakers with very flat sound, precise imaging and adjustable bass, now discontinued but worth buying used. Its measured preference score, a predictor of how neutral it sounds, is 5.38 against 4.72 for the Pylon Jasper Monitor 18. 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.
The Pylon Jasper Monitor 18 is the deeper-bass choice. A premium Polish monitor with ScanSpeak drivers, lively midbass punch, wide dispersion and an attractive finish. Its bass reaches about 48Hz before falling 3dB, against 59Hz for the Buchardt S400 MKII. The tradeoff: Sounds notably bright, thumpy, and fatiguing pointed directly on-axis; needs about 30° of toe-out to bring the high-frequency lift into better balance.
Buy the Buchardt S400 MKII only if you find one used in good condition; both are discontinued, and it is the better rated of the two. For a new speaker, buy the Buchardt S400 MK3, which replaces the Buchardt S400 MKII.
Looking for alternatives? See the complete Passive Home rankings.
Measured Differences
- Bass depth: the Pylon Jasper Monitor 18 reaches 32 Hz (10 dB down) against 40 Hz for the Buchardt S400 MKII, about half an octave deeper. You hear more of the lowest bass notes and kick drums.
- Tonal accuracy above the bass: with a subwoofer taking the low end, the Buchardt S400 MKII scores 7.5 against 6.3 for the Pylon Jasper Monitor 18 on the Spinorama preference scale. Its frequency response and off-axis sound are smoother, so voices and instruments sound closer to the recording.
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Specifications Side By Side
| Buchardt S400 MKII | Pylon Jasper Monitor 18 | |
|---|---|---|
| Price | $2400 per pair Discontinued | $2,499 per pair Discontinued |
| Ranked | #111 of 222 in Large Size Bookshelf Speakers | #186 of 222 in Large Size Bookshelf Speakers |
| Bass Extension (-10dB) | 40Hz (measured, Erin’s Audio Corner) | 32Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-3dB) | 59Hz (measured, Erin’s Audio Corner) | 48Hz (measured, Erin’s Audio Corner) |
| Dimensions | 14.4”H x 7”W x 11”D (365.8 x 177.8 x 279.4 mm) | 16.9”H x 7.9”W x 16.3”D (430.0 x 200.0 x 413.0 mm) |
| Impedance | 4 ohms nominal, 3 ohms minimum (measured, Erin’s Audio Corner) | 4 ohms nominal, 4.4 ohms minimum (measured, Erin’s Audio Corner) |
| Sensitivity | 84.7dB (measured, Erin’s Audio Corner; 87dB manufacturer specified) | 83dB (measured by Erin’s Audio Corner) |
| Drivers | 6.5” aluminum cone woofer, 1” soft dome tweeter | 1” tweeter + 6.5” woofer |
| Weight | 16.5 lbs (7.5 kg) each | 34.2 lbs (15.5 kg) |
| Woofer Cabinet | ported | ported, rear |
| Spinorama Preference Score | 5.38 | 4.72 |
| Spinorama Preference Score with Perfect Sub | 7.46 | 6.34 |
| DIY Kit | No | No |
Where the Ratings Come From
- Buchardt S400 MKII: Spinorama.org measurements and reviews by Erin’s Audio Corner.
- Pylon Jasper Monitor 18: Spinorama.org measurements and reviews by Erin’s Audio Corner.
This comparison is generated from the ratings, specifications and measurements on each product’s own page, and it updates when that data changes. How we rank explains how each rating is decided.
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