Short answer: the AsciLab C6B. It ranks #6 of 216 bookshelf speakers by sound quality (rated 4.7/5) at $1,145 and is still sold new; the Revel Concerta2 M16 ranks #63 (rated 4.1/5) and is discontinued, so it is only an option used.
The AsciLab C6B is the more accurate, deeper-bass pick. Two-way design pairing a 1” aluminum ceramic dome tweeter on a large waveguide with a 6” aluminum ceramic cone woofer, crossed over at 1.1kHz, plus a rear passive radiator. Its measured preference score, a predictor of how neutral it sounds, is 6.33 against 5.06 for the Revel Concerta2 M16. Its bass reaches about 54Hz before falling 3dB, against 60.1Hz for the Revel Concerta2 M16. The catch: Bass rolls off around 50Hz in-room (F3 54Hz, F10 35Hz), so a subwoofer is needed for real extension below that.
What the Revel Concerta2 M16 does well: CEA2034 spinorama shows an on-axis response that’s essentially flat from 200Hz to 10kHz, with some bass boost around 100Hz. Watch for: Harmonic distortion shows a notable peak around 80Hz and a sharp spike around 350Hz, plus the woofer appears to get a bit unhappy right before handing off to the tweeter.
Buy the AsciLab C6B. It is rated higher for sound quality, and the Revel Concerta2 M16 is discontinued, so it is only available used.
Want more options? Browse the full Passive Home rankings.
Specifications Side By Side
| AsciLab C6B | Revel Concerta2 M16 | |
|---|---|---|
| Price | $1145 per pair | $600 per pair used (about), Discontinued |
| Ranked | #6 of 216 in Large Size Bookshelf Speakers | #63 of 216 in Large Size Bookshelf Speakers |
| Bass Extension (-10dB) | 35Hz (measured, Erin’s Audio Corner) | 41.6Hz (measured, Audio Science Review) |
| Bass Extension (-3dB) | 54Hz (measured, Erin’s Audio Corner) | 60.1Hz (measured, Audio Science Review) |
| Dimensions | 15.7”H x 8”W x 10.4”D (398.8 x 203.2 x 264.2 mm) | 14.8”H x 8.6”W x 10.8”D (374.7 x 218.4 x 273.3 mm) |
| Impedance | 4 ohms nominal, 2.6 ohms minimum (measured, Erin’s Audio Corner) | 6 ohms |
| Sensitivity | 85.6dB (measured, Erin’s Audio Corner) | 86dB |
| Drivers | 6” Aluminium Ceramic Cone with cast Aluminium Chassis woofer, 1” Aluminium Ceramic Dome tweeter | 25mm tweeter + 165mm woofer |
| Weight | 18.5 lbs (8.4 kg) each | 32 lbs (14.5 kg) |
| Woofer Cabinet | passive radiator | ported, rear |
| Spinorama Preference Score | 6.33 | 5.06 |
| Spinorama Preference Score with Perfect Sub | 8.28 | 7.28 |
| DIY Kit | No | No |
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: AsciLab C6B (measured by Erin’s Audio Corner) and Revel Concerta2 M16 (measured by Audio Science Review), via spinorama.org.
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The Two Speakers In Full
AsciLab C6B: $1145 per pair Ascilab $1145 eBay
Same family: the AsciLab C5B (smaller bookshelf, rated 4.2/5).
Pros: Two-way design pairing a 1” aluminum ceramic dome tweeter on a large waveguide with a 6” aluminum ceramic cone woofer, crossed over at 1.1kHz, plus a rear passive radiator. Unusual trait: horizontal radiation actually widens at higher frequencies instead of narrowing like most two-way designs, which keeps image focus and soundstage depth consistent whether you toe the speakers in or out (5-10° off-axis was the sweet spot in testing). Vertical radiation also stays wide straight through the 2kHz crossover region, so the sound doesn’t collapse when standing up: unusual at this price. CA2034 measurements show strong on-axis linearity, listening window, early reflections, and directivity. Midrange and tweeter distortion stay very low even at 96dB, holding up against a $5,900 Arendal speaker in that regard despite roughly a 5x price gap. At $1145 shipped to the US, the reviewer calls it the best-value bookshelf speaker he’s tested, rivaling speakers 2-5x the price. Measured bass extension of 54Hz (-3dB), with a measured sensitivity of 85.6dB.
Cons: Bass rolls off around 50Hz in-room (F3 54Hz, F10 35Hz), so a subwoofer is needed for real extension below that. Low-frequency harmonic distortion increases substantially at 96dB versus 86dB, though it’s second-order and less audible than it looks on paper. Minimum impedance dips to 2.6 ohms (EPDR as low as 1.2 ohms), so it wants an amplifier comfortable driving 4-ohm loads, ideally 100W or more. At 102dB, compression noticeably eats into midrange, bass, and some treble output. Shipping to the US adds roughly $200 on top of AsciLab’s list price. Against the reviewer’s reference Audiofirst Fidelia at a similar price, has slightly less lower-midrange body (about 1dB difference) and a smaller perceived soundstage size.
Full AsciLab C6B review and specifications →
| Bass Extension (-10dB) | 35Hz (measured, Erin’s Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 54Hz (measured, Erin’s Audio Corner) |
| DIY Kit | No |
| Dimensions | 15.7”H x 8”W x 10.4”D (398.8 x 203.2 x 264.2 mm) |
| Drivers | 6” Aluminium Ceramic Cone with cast Aluminium Chassis woofer, 1” Aluminium Ceramic Dome tweeter |
| Impedance | 4 ohms nominal, 2.6 ohms minimum (measured, Erin’s Audio Corner) |
| Sensitivity | 85.6dB (measured, Erin’s Audio Corner) |
| Spinorama Preference Score | 6.33 |
| Spinorama Preference Score with Perfect Sub | 8.28 |
| Weight | 18.5 lbs (8.4 kg) each |
| Woofer Cabinet | passive radiator |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
Revel Concerta2 M16: $600 per pair used (about) Discontinued eBay
Same family: the Revel Concerta2 F35 (smaller floorstanding, rated 4.5/5), the Revel Concerta2 F36 (larger floorstanding, estimated 4.6/5) and the Revel Concerta2 C25 (center, rated 4.1/5).
Pros: CEA2034 spinorama shows an on-axis response that’s essentially flat from 200Hz to 10kHz, with some bass boost around 100Hz. Predicted in-room response is very nice, with just extra bass and a bit of roll-off above 20kHz: the reviewer calls it “nice!” Distortion is well controlled through most of the range at both test levels. Measured bass extension of 60.1Hz (-3dB).
Cons: Harmonic distortion shows a notable peak around 80Hz and a sharp spike around 350Hz, plus the woofer appears to get a bit unhappy right before handing off to the tweeter. Cumulative spectral decay (waterfall) shows some lingering resonances in the 300Hz-1kHz region. The reviewer cautions not to over-cover the cabinet/grille area with thin fabric, as it can audibly affect the top-end response. Discontinued.
Full Revel Concerta2 M16 review and specifications →
| Released | 2015 (11 years ago) |
|---|---|
| Bass Extension (-10dB) | 41.6Hz (measured, Audio Science Review) |
| Bass Extension (-3dB) | 60.1Hz (measured, Audio Science Review) |
| DIY Kit | No |
| Dimensions | 14.8”H x 8.6”W x 10.8”D (374.7 x 218.4 x 273.3 mm) |
| Drivers | 25mm tweeter + 165mm woofer |
| Impedance | 6 ohms |
| Sensitivity | 86dB |
| Spinorama Preference Score | 5.06 |
| Spinorama Preference Score with Perfect Sub | 7.28 |
| Weight | 32 lbs (14.5 kg) |
| Woofer Cabinet | ported, rear |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
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- Revel Concerta2 M16 vs ELAC DBR62
- Revel Concerta2 M16 vs Yamaha NS-800A
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