Short answer: the Ascend Acoustics Sierra-LX. It ranks #37 of 222 bookshelf speakers by sound quality, rated 4.3/5, at $1,598; the Dynaudio Special Forty ranks #148, rated 3.5/5, and costs $3,600, which makes this an easy call rather than a real tradeoff.
Why pick the Dynaudio Special Forty: Premium bookshelf speakers with strong output, wide dispersion and fairly deep bass from a compact rear ported cabinet. Watch for: A glaring, sometimes sibilant quality around 3-4kHz was the most noticeable issue in listening, the one thing the reviewer would want notched out with EQ.
The Ascend Acoustics Sierra-LX is the more accurate, deeper-bass pick. A compact bookshelf speaker with very neutral, flat sound, a wide soundstage, and surprisingly deep bass in a bamboo cabinet. Its measured preference score, a predictor of how neutral it sounds, is 6.63 against 4.73 for the Dynaudio Special Forty. Its bass reaches about 47Hz before falling 3dB, against 54Hz for the Dynaudio Special Forty. The tradeoff: Very low sensitivity at about 81dB, so it needs a genuinely powerful amplifier to reach normal listening levels.
Buy the Ascend Acoustics Sierra-LX. It is rated higher for sound quality than the Dynaudio Special Forty and costs less, so only choose the other one for a particular feature it does better.
Looking for alternatives? See the complete Passive Home rankings.
Premium bookshelf speakers with strong output, wide dispersion and fairly deep bass from a compact rear ported cabinet.
A compact bookshelf speaker with very neutral, flat sound, a wide soundstage, and surprisingly deep bass in a bamboo cabinet.
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Specifications Side By Side
| Dynaudio Special Forty | Ascend Acoustics Sierra-LX | |
|---|---|---|
| Price | $3600 per pair | $1598 per pair |
| Ranked | #148 of 222 in Large Size Bookshelf Speakers | #37 of 222 in Large Size Bookshelf Speakers |
| Bass Extension (-10dB) | 39Hz (measured, Erin’s Audio Corner) | 38Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-3dB) | 54Hz (measured, Erin’s Audio Corner) | 47Hz (measured, Erin’s Audio Corner) |
| Dimensions | 14.1”H x 7.7”W x 12.1”D (358.1 x 195.6 x 307.3 mm) | 14.3” x 7.5” x 10.5” (362 x 191 x 267 mm) |
| Impedance | 6 ohms nominal (4.9 ohms minimum above 80Hz, measured, Erin’s Audio Corner) | 8 ohms nominal (5.5 ohms minimum) |
| Sensitivity | 83.5dB (measured, Erin’s Audio Corner; 86dB manufacturer specified) | 81dB (2.83V/1m, measured by Erin’s Audio Corner) |
| Drivers | 5.9” MSP (Magnesium Silicate Polymer) cone woofer, 1” Esotar soft dome tweeter | 6” aluminum cone woofer, 26mm dome tweeter |
| Weight | 17.9 lbs (8.1 kg) each | 20.9 lbs (9.5 kg) |
| Woofer Cabinet | ported | Bass reflex, flared rear port |
| Spinorama Preference Score | 4.73 | 6.63 |
| Spinorama Preference Score with Perfect Sub | 6.74 | 8.44 |
| DIY Kit | No | No |
| Power Handling | - | 350W continuous, 500W peak |
| Frequency Response | - | 28Hz - 23kHz (in-room, manufacturer specified) |
| Country | - | USA |
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