AsciLab C6B vs Ascend Acoustics CMT-340 SE2

Last updated: September 16, 2026

Short answer: the AsciLab C6B on measured sound quality, the Ascend Acoustics CMT-340 SE2 on price. The AsciLab C6B ranks #7 of 130 bookshelf speakers at $1145. The Ascend Acoustics CMT-340 SE2 ranks #23 at $798, $347 cheaper.

AsciLab C6B vs Ascend Acoustics CMT-340 SE2

What the AsciLab C6B offers: 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 $935 (about $1,135 shipped to the US), the reviewer calls it the best-value bookshelf speaker he’s tested, rivaling speakers 2-5x the price. Watch for: 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 the $935 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.

What the Ascend Acoustics CMT-340 SE2 offers: High-quality manufacturer Klippel NFS data shows 0.295dB on-axis average absolute deviation, 0.531 listening-window smoothness, and a strong 7.17 preference score with a subwoofer. Its dual 6.5-inch woofers, 92dB anechoic sensitivity, and 240W continuous power rating support high output and dynamics. Watch for: Bass rolls off early for the cabinet size, measuring 77.6Hz at -3dB, 64.5Hz at -6dB, and 48.3Hz at -12dB; the preference score without a subwoofer is only 4.51. The 4.35 sound-power directivity-index standard deviation also indicates more off-axis variation than the strongest designs, and the rear port needs placement clearance.

Buy the AsciLab C6B if sound quality is the priority over the price, or the Ascend Acoustics CMT-340 SE2 if the price is the priority over sound quality.

Still deciding? The full Passive Home rankings cover every ranked option.

Specifications Side By Side

AsciLab C6B Ascend Acoustics CMT-340 SE2
Price$1145 per pair$798 per pair
Ranked#7 of 130 in Large Size Bookshelf Speakers#23 of 130 in Large Size Bookshelf Speakers
Bass Extension (-10dB)35Hz (measured, Erin's Audio Corner)approximately 53Hz (measured, spinorama.org)
Bass Extension (-3dB)54Hz (measured, Erin's Audio Corner)77.6Hz (measured, spinorama.org)
Dimensions15.7"H x 8"W x 10.4"D (398.8 x 203.2 x 264.2 mm)21 x 7.5 x 10.5 in each
Impedance4 ohms nominal, 2.6 ohms minimum (measured, Erin's Audio Corner)8 ohms nominal
Sensitivity85.6dB (measured, Erin's Audio Corner)92dB at 2.83V/1m anechoic
Drivers6" Aluminium Ceramic Cone with cast Aluminium Chassis woofer, 1" Aluminium Ceramic Dome tweeterTwo 6.5-inch woofers; 27mm soft-dome tweeter
Weight18.5 lbs (8.4 kg) each29.1 lbs (13.2 kg) each
Woofer Cabinetpassive radiator-
Spinorama Preference Score5.664.51
Spinorama Preference Score with Perfect Sub7.607.17
Power Handling-240W continuous; 400W short-term peak

How AsciLab C6B compares with other leading options:

Prices on this page were last checked September 16, 2026 at 12:41 AM 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.

The Two Speakers In Full

AsciLab C6B: $1145 per pair Ascilab eBay

AsciLab C6B ranking card

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 $935 (about $1,135 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 the $935 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.

Bass Extension (-10dB)35Hz (measured, Erin's Audio Corner)
Bass Extension (-3dB)54Hz (measured, Erin's Audio Corner)
Dimensions15.7"H x 8"W x 10.4"D (398.8 x 203.2 x 264.2 mm)
Drivers6" Aluminium Ceramic Cone with cast Aluminium Chassis woofer, 1" Aluminium Ceramic Dome tweeter
Impedance4 ohms nominal, 2.6 ohms minimum (measured, Erin's Audio Corner)
Sensitivity85.6dB (measured, Erin's Audio Corner)
Spinorama Preference Score5.66
Spinorama Preference Score with Perfect Sub7.60
Weight18.5 lbs (8.4 kg) each
Woofer Cabinetpassive radiator

Ascend Acoustics CMT-340 SE2: $798 per pair Ascend Acoustics eBay

Ascend Acoustics CMT-340 SE2 ranking card

Pros: High-quality manufacturer Klippel NFS data shows 0.295dB on-axis average absolute deviation, 0.531 listening-window smoothness, and a strong 7.17 preference score with a subwoofer. Its dual 6.5-inch woofers, 92dB anechoic sensitivity, and 240W continuous power rating support high output and dynamics. Measured bass extension of 77.6Hz (-3dB).

Cons: Bass rolls off early for the cabinet size, measuring 77.6Hz at -3dB, 64.5Hz at -6dB, and 48.3Hz at -12dB; the preference score without a subwoofer is only 4.51. The 4.35 sound-power directivity-index standard deviation also indicates more off-axis variation than the strongest designs, and the rear port needs placement clearance.

Bass Extension (-10dB)approximately 53Hz (measured, spinorama.org)
Bass Extension (-3dB)77.6Hz (measured, spinorama.org)
Dimensions21 x 7.5 x 10.5 in each
DriversTwo 6.5-inch woofers; 27mm soft-dome tweeter
Impedance8 ohms nominal
Power Handling240W continuous; 400W short-term peak
Sensitivity92dB at 2.83V/1m anechoic
Spinorama Preference Score4.51
Spinorama Preference Score with Perfect Sub7.17
Weight29.1 lbs (13.2 kg) each