Short answer: the KEF Q100 for point-source imaging; the ELAC BS U5 trades that for crossover distortion, though neither ranks well in its class. The Q100’s 5.25-inch Uni-Q coaxial driver keeps tweeter and woofer aligned for consistent imaging, but its spinorama shows broad deviations: a lift from 700Hz-1.5kHz and again from 5kHz up, plus a cancellation notch around 1.4kHz. The BS U5 is fairly even on-axis to 3kHz yet exceeds 3% distortion at its mid-range crossover. Both are rated below 3.0/5 among the 90 bookshelf speakers, and the Philharmonic Ceramic Mini, ranked #2 at $900, is a better place to start if sound quality matters.
Buy the ELAC BS U5 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, start with the Philharmonic Ceramic Mini instead.
Want more options? Browse the full Passive Home rankings.
Specifications Side By Side
| ELAC BS U5 | KEF Q100 | |
|---|---|---|
| Price | $856 per pair Discontinued | $550 per pair Discontinued |
| Ranked | #60 of 90 in Medium Size Bookshelf Speakers | #71 of 90 in Medium Size Bookshelf Speakers |
| Bass Extension (-3dB) | 63Hz (measured, Audio Science Review) | 85Hz (measured, Audio Science Review) |
| Bass Extension (-10dB) | 41Hz (derived, log-interpolated between spinorama.org -9dB/-12dB points) | 65Hz (measured, Audio Science Review) |
| Drivers | 1” tweeter + 5.25” woofer | 5.25” Uni-Q aluminum coaxial driver, 1” aluminum dome tweeter |
| Weight | 13.2 lbs (6 kg) | 13 lbs (5.9 kg) each |
| Sensitivity | 83dB (2.83V/1m, measured, Audio Science Review) | 85dB (2.83V/1m, measured, Audio Science Review) |
| Impedance | 4 ohms nominal (3.4 ohms minimum) | 8 ohms nominal |
| Dimensions | 13.4”H x 7”W x 11.5”D (339.1 x 178.0 x 293.1 mm) | 11.8”H x 7.1”W x 10.7”D (300 x 180 x 272 mm) |
| Woofer Cabinet | ported, rear | ported, rear |
| Spinorama Preference Score | 4.71 (spinorama.org) | 4.96 (spinorama.org) |
| Spinorama Preference Score with Perfect Sub | 6.79 (spinorama.org) | 7.24 (spinorama.org) |
| DIY Kit | No | No |
| Frequency Response | - | 49Hz - 40kHz (+/-3dB) (Manufacturer specified) |
Related Speaker Comparisons
More worthwhile head-to-heads for ELAC BS U5:
- ELAC BS U5 vs Ascend Sierra 1 v2
- KEF LS50 Meta vs ELAC BS U5
- ELAC BS U5 vs Arendal 1961 Monitor
- ELAC BS U5 vs Revel M105
- ELAC BS U5 vs Klipsch RP-500M II
Prices on this page were last checked October 2, 2026 at 10:18 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.
As an eBay Partner, we may be compensated if you make a purchase.
The Two Speakers In Full
ELAC BS U5: $856 per pair Discontinued eBay
Pros: This slim three-way coaxial design (an Andrew Jones creation) shows a fairly even on-axis response up to 3kHz, with off-axis behavior notably smoother than the on-axis curve. Predicted in-room response looks like it should give good tonality. Vertical directivity is better than average, a benefit of the coaxial layout. Measured bass extension of 63Hz (-3dB), with a measured sensitivity of 83dB.
Cons: Distortion is very high right at both crossover points (around 270Hz (mid-range) and 2700Hz (tweeter)) at both 86dB and 96dB SPL/1m, exceeding 3% at the mid-range crossover. Minimum impedance dips to 3.4 ohms with a possible resonance around 500Hz visible in the impedance/phase curve. Discontinued.
Full ELAC BS U5 review and specifications →
| Bass Extension (-10dB) | 41Hz (derived, log-interpolated between spinorama.org -9dB/-12dB points) |
|---|---|
| Bass Extension (-3dB) | 63Hz (measured, Audio Science Review) |
| DIY Kit | No |
| Dimensions | 13.4”H x 7”W x 11.5”D (339.1 x 178.0 x 293.1 mm) |
| Drivers | 1” tweeter + 5.25” woofer |
| Impedance | 4 ohms nominal (3.4 ohms minimum) |
| Sensitivity | 83dB (2.83V/1m, measured, Audio Science Review) |
| Spinorama Preference Score | 4.71 (spinorama.org) |
| Spinorama Preference Score with Perfect Sub | 6.79 (spinorama.org) |
| Weight | 13.2 lbs (6 kg) |
| Woofer Cabinet | ported, rear |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- ELAC BS U5 vs Acoustic Energy AE100 Mk2
- ELAC BS U5 vs Dynaudio Emit M10
- ELAC BS U5 vs Dynaudio X14
- ELAC BS U5 vs Pioneer SP-BS22-LR (Philharmonic AAM Mod)
- ELAC BS U5 vs JBL L52 Classic
- ELAC BS U5 vs JBL Stage 250B
- ELAC BS U5 vs JBL Stage A120
- ELAC BS U5 vs Paradigm Monitor SE Atom
- See all 32 comparisons
KEF Q100: $550 per pair Discontinued eBay
Newer model: the KEF Q1 Meta, ranked higher, rated 3.6/5.
Pros: 5.25” Uni-Q coaxial driver keeps the tweeter and woofer point-source aligned for consistent imaging. 86dB sensitivity is reasonably easy to drive. Measured bass extension of 85Hz (-3dB), with a measured sensitivity of 85dB.
Cons: CEA2034 spinorama shows broad, audible deviations from flat rather than narrow peaks: a lift from 700Hz-1.5kHz and again from 5kHz up, plus a cancellation notch around 1.4kHz from port/cabinet interaction. Bass sensitivity drops to about 80dB and impedance falls below 4 ohms in the bass, demanding a capable amplifier. The reviewer heard boomy, buzzing bass that improved somewhat with the port plugged, and could not recommend it, calling the famous reputation more about looks than sound. Discontinued.
Full KEF Q100 review and specifications →
| Bass Extension (-10dB) | 65Hz (measured, Audio Science Review) |
|---|---|
| Bass Extension (-3dB) | 85Hz (measured, Audio Science Review) |
| DIY Kit | No |
| Dimensions | 11.8”H x 7.1”W x 10.7”D (300 x 180 x 272 mm) |
| Drivers | 5.25” Uni-Q aluminum coaxial driver, 1” aluminum dome tweeter |
| Frequency Response | 49Hz - 40kHz (+/-3dB) (Manufacturer specified) |
| Impedance | 8 ohms nominal |
| Sensitivity | 85dB (2.83V/1m, measured, Audio Science Review) |
| Spinorama Preference Score | 4.96 (spinorama.org) |
| Spinorama Preference Score with Perfect Sub | 7.24 (spinorama.org) |
| Weight | 13 lbs (5.9 kg) each |
| Woofer Cabinet | ported, rear |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons