Short answer: the KEF Q150 for better sound quality, the ELAC Debut 2.0 B5.2 for the lower price. The KEF Q150 ranks #14 of 34 bookshelf speakers at $350. The ELAC Debut 2.0 B5.2 ranks #18 at $329, $21 cheaper.
What the KEF Q150 offers: Two-way coaxial (Uni-Q) design with a 1” dome tweeter and 5.25” mid-range time-aligned in a single driver assembly, available in ported or sealed configuration. Watch for: A high-frequency lift in the estimated in-room response makes it sound noticeably brighter in an untreated room than in a heavily acoustically-treated one - a real preference factor depending on your room’s furnishings.
What the ELAC Debut 2.0 B5.2 offers: Good horizontal directivity: the off-axis curves track the on-axis response closely, so the broad tonal error responds predictably to EQ. Watch for: Erin measured a broad +3dB step beginning around 1.5kHz; the resulting elevated upper range sounds tonally uneven even though it is not a narrow, sharp resonance.
Buy the KEF Q150 if sound quality matters more than the price. Buy the ELAC Debut 2.0 B5.2 if the price matters more than sound quality.
Specifications Side By Side
| KEF Q150 | ELAC Debut 2.0 B5.2 | |
|---|---|---|
| Price | $350 Discontinued | $329.00 |
| Ranked | #14 of 34 in Medium Size Bookshelf Speakers | #18 of 34 in Medium Size Bookshelf Speakers |
| Bass Extension (-10dB) | 44Hz (measured, Erin’s Audio Corner) | 40Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-3dB) | 51Hz (measured, Erin’s Audio Corner) | 60Hz (measured, Erin’s Audio Corner) |
| Dimensions | 11.9"H x 7.1"W x 10.9"D (303 x 180 x 278 mm) | 13.4"H x 7.1"W x 9.2"D (341 x 180 x 234 mm) |
| Impedance | 8 ohms nominal, about 4.7 ohms minimum (measured, Erin’s Audio Corner) | 6 ohms nominal (manufacturer specified) |
| Sensitivity | ~85dB (300Hz-3kHz on-axis, measured, Erin’s Audio Corner) | About 83dB after recommended EQ (measured, Erin’s Audio Corner; 86dB manufacturer specified) |
| Drivers | 130mm (5.25") aluminium Uni-Q woofer, 25mm (1") vented aluminium dome tweeter | 5.25" aramid-fiber woofer, 1" cloth-dome tweeter |
| Discontinued | Yes | - |
| Weight | 12.3 lbs / 5.6 kg each | 13 lbs / 5.9 kg each |
| Woofer Cabinet | ported, rear | ported, front |
Related Speaker Comparisons
More useful head-to-heads from the same speaker class:
- Klipsch RP-500M II vs Neumi Silk 4
- Klipsch RP-500M II vs Sony SS-CS5 M2
- JBL Studio 530 vs Zaph Audio ZA5.2 TM
- ELAC Debut 2.0 B5.2 vs JBL Stage 2 250B
- KEF Q150 vs JBL Stage 2 250B
The Two Speakers In Full
KEF Q150: $350 Discontinued Amazon
Pros: Two-way coaxial (Uni-Q) design with a 1” dome tweeter and 5.25” mid-range time-aligned in a single driver assembly, available in ported or sealed configuration. Exceptional soundstage depth, a hallmark of KEF’s coaxial designs that the reviewer says few other speakers match. Bass extension reaches into kick-drum territory, respectable for a compact bookshelf speaker. Resonances present in measurements are consistent across on- and off-axis readings, meaning they can be effectively corrected with EQ. Distortion profile is essentially the same whether run sealed or ported, since a subwoofer crossover point sits above where the differences would matter anyway. At its sale price (around $300, sometimes seen at $400), the reviewer considers it a clear step up from his previous budget favorite in this range, the Emotiva B1+, mainly due to the superior soundstage depth.
Cons: A high-frequency lift in the estimated in-room response makes it sound noticeably brighter in an untreated room than in a heavily acoustically-treated one - a real preference factor depending on your room’s furnishings. A mild dip in the 1-2kHz region reduces vocal fullness somewhat. Unexplained resonances appear in measurements and persist in both sealed and ported configurations, pointing to enclosure or panel vibration rather than the port. Horizontal radiation is narrower than the reviewer generally prefers from KEF’s lineup, with directivity that widens somewhat around 1.2kHz (near a resonance) and again above about 5kHz. Compression testing at high output (102dB) shows significant nonlinearity, especially at lower frequencies - noticeably worse than a comparable Arendal bookshelf speaker costing over twice as much, which held up better until 80Hz. Not intended for loud listening without a subwoofer - the woofer will over-exert itself without a high-pass filter, and the reviewer recommends crossing over at 80-120Hz. At full retail price (around $600/pair), the value proposition is far less certain than at sale pricing. Discontinued.
Full KEF Q150 review and specifications →
| Bass Extension (-10dB) | 44Hz (measured, Erin's Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 51Hz (measured, Erin's Audio Corner) |
| Dimensions | 11.9"H x 7.1"W x 10.9"D (303 x 180 x 278 mm) |
| Discontinued | Yes |
| Drivers | 130mm (5.25") aluminium Uni-Q woofer, 25mm (1") vented aluminium dome tweeter |
| Impedance | 8 ohms nominal, about 4.7 ohms minimum (measured, Erin's Audio Corner) |
| Sensitivity | ~85dB (300Hz-3kHz on-axis, measured, Erin's Audio Corner) |
| Weight | 12.3 lbs / 5.6 kg each |
| Woofer Cabinet | ported, rear |
As an eBay Partner, we may be compensated if you make a purchase.
- Links
- Reviews, Comparisons and Sound Samples
- Erin’s Audio Corner: Kef’s Cheapest Bookshelf. Is the Q150 worth your money?
- Erin’s Audio Corner Website KEF Q150
- GR-Research: KEF Q150… can it get any BETTER?
- Erin’s Audio Corner: 5 AWESOME SPEAKERS Under $1000 You Won’t Regret
- Erin’s Audio Corner: Budget Stereo Systems You Will Love
- Reddit Search for KEF Q150 Review
- Head-to-Head Comparisons
ELAC Debut 2.0 B5.2: $329.00 Amazon
Pros: Good horizontal directivity: the off-axis curves track the on-axis response closely, so the broad tonal error responds predictably to EQ. Erin demonstrated that a single high-shelf filter centered near 1.6kHz, about -2dB with Q near 2, substantially improves linearity. Moderate roughly +/-50-60 degree horizontal coverage balances room interaction and image focus. The front port makes close-to-wall placement practical. Erin measured F3 near 60Hz and F10 near 40Hz, useful extension for a compact 5.25-inch two-way. Harmonic distortion is mostly below 1% at 86dB/1m, and low-frequency distortion is better than its size might suggest. Compact cabinet and inexpensive pair pricing make it a workable EQ-assisted desktop or small-room system.
Cons: Erin measured a broad +3dB step beginning around 1.5kHz; the resulting elevated upper range sounds tonally uneven even though it is not a narrow, sharp resonance. Native response spans roughly -2.6 to +4dB around the mean, so this is not a neutral speaker without correction. Sensitivity is only about 83dB after correcting the shelf, demanding materially more amplifier voltage than ELAC’s 86dB specification implies. Vertical response changes substantially outside roughly +/-10 degrees of tweeter height. Dynamic compression is the larger limitation: at the highest sweep level it loses roughly 1-1.5dB through the midrange, and even the 86dB trace shows unusual nonlinearity that may involve crossover heating. At about 96dB, multitone distortion rises audibly around 600Hz; an 80-120Hz subwoofer crossover helps but does not turn it into a high-output design. Erin recommends the larger B6.2 instead when EQ is unavailable.
Full ELAC Debut 2.0 B5.2 review and specifications →
| Bass Extension (-10dB) | 40Hz (measured, Erin's Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 60Hz (measured, Erin's Audio Corner) |
| Dimensions | 13.4"H x 7.1"W x 9.2"D (341 x 180 x 234 mm) |
| Drivers | 5.25" aramid-fiber woofer, 1" cloth-dome tweeter |
| Impedance | 6 ohms nominal (manufacturer specified) |
| Sensitivity | About 83dB after recommended EQ (measured, Erin's Audio Corner; 86dB manufacturer specified) |
| Weight | 13 lbs / 5.9 kg each |
| Woofer Cabinet | ported, front |
As an eBay Partner, we may be compensated if you make a purchase.
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons


