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 ATC SCM19 ranks #209, rated 2.4/5, and costs $3,750, so there is not much of a tradeoff to weigh.
The Ascend Acoustics Sierra-LX is the more accurate, deeper-bass option. 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 4.61 for the ATC SCM19. Its bass reaches about 47Hz before falling 3dB, against 60Hz for the ATC SCM19. The catch: Very low sensitivity at about 81dB, so it needs a genuinely powerful amplifier to reach normal listening levels.
What the ATC SCM19 does well: A heavy, sealed pro style ATC bookshelf speaker with a very dense cabinet and low distortion at high volume. The catch: Some stored energy resonance around 500-700Hz, 4dB bump around 700Hz.
Buy the Ascend Acoustics Sierra-LX. It is rated higher for sound quality than the ATC SCM19 and costs less, so only choose the other one for a particular feature it does better.
Still deciding? The full Passive Home rankings cover every ranked option.
A compact bookshelf speaker with very neutral, flat sound, a wide soundstage, and surprisingly deep bass in a bamboo cabinet.
A heavy, sealed pro style ATC bookshelf speaker with a very dense cabinet and low distortion at high volume.
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Specifications Side By Side
| Ascend Acoustics Sierra-LX | ATC SCM19 | |
|---|---|---|
| Price | $1598 per pair | $3750 per pair |
| Ranked | #37 of 222 in Large Size Bookshelf Speakers | #209 of 222 in Large Size Bookshelf Speakers |
| Bass Extension (-10dB) | 38Hz (measured, Erin’s Audio Corner) | 34Hz (measured, Audio Science Review) |
| Bass Extension (-3dB) | 47Hz (measured, Erin’s Audio Corner) | 60Hz (measured, Audio Science Review) |
| Dimensions | 14.3” x 7.5” x 10.5” (362 x 191 x 267 mm) | 17.2”H x 10.4”W x 11.8”D (436.9 x 264.2 x 299.7 mm) |
| Impedance | 8 ohms nominal (5.5 ohms minimum) | 6 ohms |
| Sensitivity | 81dB (2.83V/1m, measured by Erin’s Audio Corner) | 85dB (measured, Audio Science Review) |
| Drivers | 6” aluminum cone woofer, 26mm dome tweeter | 5.9” Super Linear Magnet cone woofer, 1” soft dome tweeter |
| Weight | 20.9 lbs (9.5 kg) | 39.2 lbs (17.8 kg) each |
| Woofer Cabinet | Bass reflex, flared rear port | sealed |
| Power Handling | 350W continuous, 500W peak | - |
| Frequency Response | 28Hz - 23kHz (in-room, manufacturer specified) | - |
| Country | USA | - |
| Spinorama Preference Score | 6.63 | 4.61 |
| Spinorama Preference Score with Perfect Sub | 8.44 | 7.03 |
| DIY Kit | No | No |
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