Short answer: the Tannoy System 600 for better sound quality, the Ascend CBM-170 SE for the lower price. The Tannoy System 600 ranks #101 of 105 bookshelf speakers at $400. The Ascend CBM-170 SE ranks #102 at $384, $16 cheaper.
On the Ascend CBM-170 SE side: US-manufactured 2-way with a custom SEAS silk dome tweeter and low harmonic distortion. The catch: On-axis response starts peaking above 1kHz and keeps rising, which Amir predicted would create a bright, potentially fatiguing tonal balance - a character he says “can become grating” over time.
What the Tannoy System 600 offers: Impedance is well controlled, and the concentric dual-driver layout gives it consistent horizontal and vertical response relative to typical non-coaxial 2-ways of its era. Watch for: CEA2034 spinorama shows a large suck-out right at the crossover frequency where the two drivers fail to overlap properly, plus general peaking beforehand - the reviewer noted “no measurement seems to have been used to optimize this design.” Predicted in-room response is correspondingly poor.
Buy the Ascend CBM-170 SE if the price matters more than sound quality. Buy the Tannoy System 600 if sound quality matters more than the price.
If sound quality matters at all to you, skip both of these and look higher up the 105 bookshelf speakers instead.
Specifications Side By Side
| Ascend CBM-170 SE | Tannoy System 600 | |
|---|---|---|
| Price | $384 discontinued, superseded by CBM-170SE2 | $400 Discontinued |
| Ranked | #102 of 105 in Large Size Bookshelf Speakers | #101 of 105 in Large Size Bookshelf Speakers |
| Drivers | 6.5" proprietary composite polygel cone woofer, 27mm custom SEAS soft dome tweeter | 6.5" Tannoy Dual Concentric driver (type 1678) |
| Dimensions | 12H x 9W x 10D in | 8.7"H x 14.2"W x 11.4"D (220 x 360 x 290 mm) |
| Weight | 14 lbs / 6.35 kg each | 20.9 lbs / 9.5 kg pair (cabinet) |
| Sensitivity | 91dB (2.83V/1m, manufacturer specified, in-room) | approx. 84dB (2.83V/1m, measured, Audio Science Review - low confidence, no flat reference plateau) |
| Bass Extension (-3dB) | approx. 80Hz (measured, Audio Science Review) | approx. 73Hz - low confidence, response never reaches a flat reference level (measured, Audio Science Review) |
| Bass Extension (-10dB) | approx. 50Hz (measured, Audio Science Review) | approx. 48Hz - low confidence, response never reaches a flat reference level (measured, Audio Science Review) |
| Impedance | 8 ohms | 8 ohms nominal |
| Discontinued | - | Yes |
| Frequency Response | - | 52Hz - 20kHz +/-3dB (Manufacturer specified) |
| Power Handling | - | 50-150W recommended |
| Woofer Cabinet | - | ported, flared tubes |
Related Speaker Comparisons
More useful head-to-heads from the same speaker class:
- Polk Monitor XT20 vs Zu Audio Method
- ELAC Debut 2.0 B6.2 vs Zu Audio Method
- HiVi Swans 3.1A Sehlin Sound Solutions mod vs Zu Audio Method
- Tannoy System 600 vs Dayton Audio MK602X
- Fosi Audio SP601 vs Dayton Audio MK602X
The Two Speakers In Full
Ascend CBM-170 SE: $384 discontinued, superseded by CBM-170SE2
Pros: US-manufactured 2-way with a custom SEAS silk dome tweeter and low harmonic distortion. Solid cabinet construction for the price class.
Cons: On-axis response starts peaking above 1kHz and keeps rising, which Amir predicted would create a bright, potentially fatiguing tonal balance - a character he says “can become grating” over time. The small tweeter paired with a larger woofer lacking a waveguide causes significant off-axis coloration, contradicting the manufacturer’s accuracy claims. Impedance dips below 4 ohms in the bass, and cabinet flex was noted, comparable to cheaper competitors. Amir suggests “looking elsewhere for a better design.”
Full Ascend CBM-170 SE review and specifications →
| Bass Extension (-10dB) | approx. 50Hz (measured, Audio Science Review) |
|---|---|
| Bass Extension (-3dB) | approx. 80Hz (measured, Audio Science Review) |
| Dimensions | 12H x 9W x 10D in |
| Drivers | 6.5" proprietary composite polygel cone woofer, 27mm custom SEAS soft dome tweeter |
| Impedance | 8 ohms |
| Sensitivity | 91dB (2.83V/1m, manufacturer specified, in-room) |
| Weight | 14 lbs / 6.35 kg each |
As an eBay Partner, we may be compensated if you make a purchase.
- Reviews, Comparisons and Sound Samples
Tannoy System 600: $400 Discontinued
Pros: Impedance is well controlled, and the concentric dual-driver layout gives it consistent horizontal and vertical response relative to typical non-coaxial 2-ways of its era.
Cons: CEA2034 spinorama shows a large suck-out right at the crossover frequency where the two drivers fail to overlap properly, plus general peaking beforehand - the reviewer noted “no measurement seems to have been used to optimize this design.” Predicted in-room response is correspondingly poor. Amir ran out of time to perform a dedicated subjective listening test on this unit, but concluded from the data alone that it is “highly colored and really not something you want to put in your system.” Long discontinued; used-market only. Discontinued.
Full Tannoy System 600 review and specifications →
| Bass Extension (-10dB) | approx. 48Hz - low confidence, response never reaches a flat reference level (measured, Audio Science Review) |
|---|---|
| Bass Extension (-3dB) | approx. 73Hz - low confidence, response never reaches a flat reference level (measured, Audio Science Review) |
| Dimensions | 8.7"H x 14.2"W x 11.4"D (220 x 360 x 290 mm) |
| Discontinued | Yes |
| Drivers | 6.5" Tannoy Dual Concentric driver (type 1678) |
| Frequency Response | 52Hz - 20kHz +/-3dB (Manufacturer specified) |
| Impedance | 8 ohms nominal |
| Power Handling | 50-150W recommended |
| Sensitivity | approx. 84dB (2.83V/1m, measured, Audio Science Review - low confidence, no flat reference plateau) |
| Weight | 20.9 lbs / 9.5 kg pair (cabinet) |
| Woofer Cabinet | ported, flared tubes |
As an eBay Partner, we may be compensated if you make a purchase.
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons