Short answer: the ELAC Uni-Fi 2.0 UB52, if you are buying new, though neither ranks well in its class. The Acoustic Energy AE100 Mk2 ranks higher than it (#118 vs #143 of 178 bookshelf speakers, 2.9/5 vs 2.4/5) but is discontinued, so only consider it used; the ELAC Uni-Fi 2.0 UB52 is still sold new at $599. Both are rated below 3.0/5 among the 178 bookshelf speakers; for better sound, the Ascend Acoustics HTM-200SE2 ranks #7 at $368.
The Acoustic Energy AE100 Mk2 is the better-sounding choice. Good directivity linearity: on-axis and off-axis response track each other well despite an otherwise uneven overall response, which means the tonal problems can be EQ’d out with reasonably good success. Watch for: High-frequency level runs noticeably too hot regardless of placement: the reviewer tried four different setups (near/far from wall, on-axis, 30° off-axis) at two listening distances and couldn’t get it to sound right at any of them.
The ELAC Uni-Fi 2.0 UB52 is the deeper-bass pick. Wide, smooth horizontal directivity: beamwidth holds to about ±60 degrees up to 8kHz before narrowing. Its bass reaches about 55.7Hz before falling 3dB, against 63Hz for the Acoustic Energy AE100 Mk2. Watch for: Dipped 3db from 1.5-3kHz.
Buy the ELAC Uni-Fi 2.0 UB52 new; the Acoustic Energy AE100 Mk2 is no longer sold new, so it only makes sense as a used find.
Looking for alternatives? See the complete Passive Home rankings.
Good directivity linearity: on-axis and off-axis response track each other well despite an otherwise uneven overall response, which means the tonal problems can be EQ’d out with reasonably good success.
Amazon $399 eBay
Wide, smooth horizontal directivity: beamwidth holds to about ±60 degrees up to 8kHz before narrowing.
Amazon $599.00 eBayPrices on this page were last checked October 17, 2026 at 6:04 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.
Specifications Side By Side
| Acoustic Energy AE100 Mk2 | ELAC Uni-Fi 2.0 UB52 | |
|---|---|---|
| Price | $399 per pair Discontinued | $599.00 per pair |
| Ranked | #118 of 178 in Medium Size Bookshelf Speakers | #143 of 178 in Medium Size Bookshelf Speakers |
| Drivers | 5.25” midwoofer, 1” soft fabric dome tweeter with waveguide | 5.25” aluminum woofer, 4” aluminum midrange, 1” soft dome tweeter |
| Crossover Frequency | 2.9kHz | 200Hz / 2000Hz |
| Dimensions | 11.4”H x 6.5”W x 9.8”D (290 x 165 x 250 mm) | 13.6”H x 7.3”W x 10.8”D (346 x 185 x 275 mm) |
| Weight | 20.1 lbs (9.1 kg) each | 7.7 lbs (3.5 kg) |
| Impedance | 6 ohms nominal, 4.7 ohms minimum (measured, Erin’s Audio Corner) | 6 ohms |
| Sensitivity | 84dB (measured average, Erin’s Audio Corner) | 83.3dB (measured by Audio Science Review; 85dB manufacturer specified) |
| Bass Extension (-3dB) | 63Hz (measured, Erin’s Audio Corner) | 55.7Hz (measured, Audio Science Review) |
| Bass Extension (-10dB) | 42Hz (measured, Erin’s Audio Corner) | 38.6Hz (measured, Audio Science Review) |
| Woofer Cabinet | ported, rear slot port | ported |
| Spinorama Preference Score | 4.96 | 5.32 (spinorama.org) |
| Spinorama Preference Score with Perfect Sub | 7.18 | 7.34 (spinorama.org) |
| DIY Kit | No | No |
| Power Handling | - | 140W max |
Frequency Response Compared
Both speakers’ spinorama measurements, overlaid. A flatter line is more neutral: peaks sound forward or harsh, dips sound recessed. Each curve is shifted so its average from 300 Hz to 3 kHz sits at 0 dB, so loudness differences between the two are removed and only the shape is compared. The two were measured by different sources, so small differences, especially in the bass, can come from the measurement setup rather than the speakers.
Measurement data: Acoustic Energy AE100 Mk2 (measured by Erin’s Audio Corner) and ELAC Uni-Fi 2.0 UB52 (measured by Audio Science Review), via spinorama.org.
Related Speaker Comparisons
How Acoustic Energy AE100 Mk2 compares with other leading options: