Short answer: the Ascend Acoustics Sierra 1 v2. It ranks #3 of 179 bookshelf speakers by sound quality (rated 4.7/5) at $1,000 and is still sold new; the Acoustic Energy AE100 Mk2 ranks #119 (rated 2.9/5) and is discontinued, so it is only an option used.
The Ascend Acoustics Sierra 1 v2 is the more accurate, deeper-bass option. An extremely accurate bookshelf speaker, with a bamboo cabinet, wide even dispersion and clean output when played loud. Its measured preference score, a predictor of how neutral it sounds, is 6.65 against 4.96 for the Acoustic Energy AE100 Mk2. Its bass reaches about 55Hz before falling 3dB, against 63Hz for the Acoustic Energy AE100 Mk2. Watch for: F3 of 55Hz and F10 of 39Hz mean in-room extension tops out in the mid-40s Hz; the reviewer still recommends a subwoofer for full-range material.
The case for the Acoustic Energy AE100 Mk2: A nicely finished discontinued bookshelf speaker with wide dispersion and consistent off-axis sound that responds well to EQ. 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.
Buy the Ascend Acoustics Sierra 1 v2. It is rated higher for sound quality, and the Acoustic Energy AE100 Mk2 is discontinued, so it is only available used.
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Measured Differences
- Tonal accuracy above the bass: with a subwoofer taking the low end, the Ascend Acoustics Sierra 1 v2 scores 8.6 against 7.2 for the Acoustic Energy AE100 Mk2 on the Spinorama preference scale. Its frequency response and off-axis sound are smoother, so voices and instruments sound closer to the recording.
- Efficiency: the Acoustic Energy AE100 Mk2 is rated at 84 dB sensitivity against 81.5 dB for the Ascend Acoustics Sierra 1 v2, so it plays as loud with roughly two thirds of the amplifier power.
- Close enough not to matter: bass extension (39 Hz vs 42 Hz, 10 dB down).
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Specifications Side By Side
| Ascend Acoustics Sierra 1 v2 | Acoustic Energy AE100 Mk2 | |
|---|---|---|
| Price | $1000 per pair | $399 per pair Discontinued |
| Ranked | #3 of 179 in Medium Size Bookshelf Speakers | #119 of 179 in Medium Size Bookshelf Speakers |
| Bass Extension (-10dB) | 39Hz (measured, Erin’s Audio Corner) | 42Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-3dB) | 55Hz (measured, Erin’s Audio Corner) | 63Hz (measured, Erin’s Audio Corner) |
| Dimensions | 14.2”H x 7.5”W x 10.5”D (361.9 x 190.5 x 266.7 mm) | 11.4”H x 6.5”W x 9.8”D (290 x 165 x 250 mm) |
| Impedance | 8 ohms nominal, 7 ohms minimum (measured, Erin’s Audio Corner) | 6 ohms nominal, 4.7 ohms minimum (measured, Erin’s Audio Corner) |
| Sensitivity | 81.5dB (measured, Erin’s Audio Corner) | 84dB (measured average, Erin’s Audio Corner) |
| Drivers | 5.25” proprietary mineral-filled polypropylene cone with cast aluminum frame woofer, 26mm aluminum/magnesium alloy dome tweeter with titanium former (SEAS Titan) | 5.25” midwoofer, 1” soft fabric dome tweeter with waveguide |
| Weight | 18.5 lbs (8.4 kg) each | 20.1 lbs (9.1 kg) each |
| Woofer Cabinet | ported | ported, rear slot port |
| Spinorama Preference Score | 6.65 | 4.96 |
| Spinorama Preference Score with Perfect Sub | 8.61 | 7.18 |
| DIY Kit | No | No |
| Crossover Frequency | - | 2.9kHz |
Where the Ratings Come From
- Ascend Acoustics Sierra 1 v2: Spinorama.org measurements and reviews by Erin’s Audio Corner and Audio Science Review Ascend.
- Acoustic Energy AE100 Mk2: 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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