Short answer: the Ascend Sierra 1 v2 for better sound quality, the Sony SS-CS5 M2 for the lower price. The Ascend Sierra 1 v2 ranks #3 of 74 bookshelf speakers at $1000. The Sony SS-CS5 M2 ranks #42 at $278, $722 cheaper.
What the Sony SS-CS5 M2 offers: Added internal bracing (corners, sides, front baffle) plus an updated crossover meaningfully reduce the resonance issues that plagued the original SS-CS5, giving a smoother, more neutral character overall. A modest mid-range dip (about 1-2dB) is present but tolerable, and the reviewer would rather have this dip than a peak in that region. Slightly deeper bass than the previous version, measuring about 2dB more output around 60Hz. Distortion drops noticeably when crossed to a subwoofer around 80-120Hz, meaningfully improving midrange clarity and detail versus running full-range. Easy to drive on a standard AVR - no need for a dedicated high-power amplifier. More modern, understated waveguide look compared to the previous version’s glossy trim. Watch for: Mild sibilance in the 3-5kHz range stands out on S and T sounds in vocals. Some forwardness in the midrange noticeable on certain vocal recordings. Soundstage and sense of envelopment are comparatively flat and two-dimensional, especially next to reference-quality speakers with strong 3D imaging. Marketed as a “three-way” design mainly due to an added super-tweeter that the reviewer considers largely superfluous - it engages only at very high frequencies and adds complexity without a clearly audible benefit, when that cost might have been better spent on the main crossover. Output-limited: realistic ceiling is around the mid-90s dB SPL at a few meters, with comfortable listening closer to 75-85dB at 3-4 meters before distortion and compression become audible. Bass noticeably compresses/shelves below about 120Hz as volume increases, softening kick-drum impact at higher output. Smaller drivers and a lighter motor structure than rivals like the Polk XT20, which the reviewer generally prefers for its better directivity and higher SPL capability. Still needs a subwoofer for any real bass extension.
What the Ascend Sierra 1 v2 offers: Formaldehyde-free layered bamboo ply cabinet with a 1” dome tweeter over a 5.25” midwoofer, mated by a 4th-order acoustic crossover rather than a stock textbook design. In-room response is extremely linear - the reviewer called it “textbook” - a clear step up from the earlier V1, which had boxiness around 700Hz-1kHz and sibilance around 4-6kHz. Preference score of 8.4 with a subwoofer (6.8 without), which the reviewer calls topnotch. Wide, even horizontal radiation of about ±70° up to 6kHz. Better vertical directivity than its tweeter-to-woofer spacing would suggest, thanks to the steep 4th-order crossover slopes. No mechanical noise, port chuffing, or woofer bottoming even driven to 96dB/1m. In a three-way comparison against the Dynaudio Emit 20 and a Revel bookshelf model (all around $1,000/pair), measured as the most linear of the three and was the reviewer’s personal pick over both, despite the Dynaudio’s deeper bass and higher output capability. Independent ASR Klippel measurements corroborate Erin’s findings: superb off-axis response with only slight on-axis variations, and an in-room response the reviewer called “incredibly smooth and accurate - amazing for a non-DSP speaker.” Distortion above 200Hz at 86dB/1m is very low for the class. Watch for: F3 of 55Hz and F10 of 39Hz mean in-room extension tops out in the mid-40s Hz; the reviewer still recommends a subwoofer for full-range material. Diffraction dips appear around 3kHz and 5-6kHz, and the 1” dome tweeter starts beaming above roughly 6.7kHz, narrowing the soundstage radiation in the top octave - a straightforward consequence of dome size rather than a design flaw. At 96dB/1m the 5.25” midwoofer shows increased distortion in the midrange, likely tied to motor topology; high-passing to a subwoofer around 80Hz largely clears it up. Moderate sensitivity (~81-82dB average) with a 7-ohm minimum impedance. ASR’s power-sweep testing found response holds steady up to 96dB SPL/1m, but pushing to 102dB causes midbass below 400Hz to sag with distortion “through the roof” - a harder output ceiling than the 96dB tests alone suggest. Vertical directivity also narrows above about 1kHz, so the reviewer recommends staying at tweeter-axis height for best results.
Buy the Sony SS-CS5 M2 if the price matters more than sound quality. Buy the Ascend Sierra 1 v2 if sound quality matters more than the price.
Specifications Side By Side
| Sony SS-CS5 M2 | Ascend Sierra 1 v2 | |
|---|---|---|
| Price | $278.00 | $1000 |
| Ranked | #42 of 74 in Medium Size Bookshelf Speakers | #3 of 74 in Medium Size Bookshelf Speakers |
| Bass Extension (-10dB) | 54Hz (measured, Erin’s Audio Corner) | 39Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-3dB) | 80Hz (measured, Erin’s Audio Corner) | 55Hz (measured, Erin’s Audio Corner) |
| Dimensions | 13.2"H x 7"W x 8.7"D (335 x 178 x 220 mm) | 14.2"H x 7.5"W x 10.5"D (361.9 x 190.5 x 266.7 mm) |
| Impedance | 6 ohms | 8 ohms nominal, 7 ohms minimum (measured, Erin’s Audio Corner) |
| Sensitivity | 82.5dB | 81.5dB (measured, Erin’s Audio Corner) |
| Supertweeter | 0.75 in | - |
| Drivers | 5.12" woofer, 0.98 in tweeter | 5.25" proprietary mineral-filled polypropylene cone with cast aluminum frame woofer, 26mm aluminum/magnesium alloy dome tweeter with titanium former (SEAS Titan) |
| Weight | 9.5 lbs / 4.3 kg each | 18.5 lbs / 8.4 kg each |
| Woofer Cabinet | ported, rear | ported |
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The Two Speakers In Full
Sony SS-CS5 M2: $278.00 Amazon eBay
Pros: Added internal bracing (corners, sides, front baffle) plus an updated crossover meaningfully reduce the resonance issues that plagued the original SS-CS5, giving a smoother, more neutral character overall. A modest mid-range dip (about 1-2dB) is present but tolerable, and the reviewer would rather have this dip than a peak in that region. Slightly deeper bass than the previous version, measuring about 2dB more output around 60Hz. Distortion drops noticeably when crossed to a subwoofer around 80-120Hz, meaningfully improving midrange clarity and detail versus running full-range. Easy to drive on a standard AVR - no need for a dedicated high-power amplifier. More modern, understated waveguide look compared to the previous version’s glossy trim.
Cons: Mild sibilance in the 3-5kHz range stands out on S and T sounds in vocals. Some forwardness in the midrange noticeable on certain vocal recordings. Soundstage and sense of envelopment are comparatively flat and two-dimensional, especially next to reference-quality speakers with strong 3D imaging. Marketed as a “three-way” design mainly due to an added super-tweeter that the reviewer considers largely superfluous - it engages only at very high frequencies and adds complexity without a clearly audible benefit, when that cost might have been better spent on the main crossover. Output-limited: realistic ceiling is around the mid-90s dB SPL at a few meters, with comfortable listening closer to 75-85dB at 3-4 meters before distortion and compression become audible. Bass noticeably compresses/shelves below about 120Hz as volume increases, softening kick-drum impact at higher output. Smaller drivers and a lighter motor structure than rivals like the Polk XT20, which the reviewer generally prefers for its better directivity and higher SPL capability. Still needs a subwoofer for any real bass extension.
Full Sony SS-CS5 M2 review and specifications →
| Bass Extension (-10dB) | 54Hz (measured, Erin's Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 80Hz (measured, Erin's Audio Corner) |
| Dimensions | 13.2"H x 7"W x 8.7"D (335 x 178 x 220 mm) |
| Drivers | 5.12" woofer, 0.98 in tweeter |
| Impedance | 6 ohms |
| Sensitivity | 82.5dB |
| Supertweeter | 0.75 in |
| Weight | 9.5 lbs / 4.3 kg each |
| Woofer Cabinet | ported, rear |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
Ascend Sierra 1 v2: $1000 Ascendacoustics eBay
Pros: Formaldehyde-free layered bamboo ply cabinet with a 1” dome tweeter over a 5.25” midwoofer, mated by a 4th-order acoustic crossover rather than a stock textbook design. In-room response is extremely linear - the reviewer called it “textbook” - a clear step up from the earlier V1, which had boxiness around 700Hz-1kHz and sibilance around 4-6kHz. Preference score of 8.4 with a subwoofer (6.8 without), which the reviewer calls topnotch. Wide, even horizontal radiation of about ±70° up to 6kHz. Better vertical directivity than its tweeter-to-woofer spacing would suggest, thanks to the steep 4th-order crossover slopes. No mechanical noise, port chuffing, or woofer bottoming even driven to 96dB/1m. In a three-way comparison against the Dynaudio Emit 20 and a Revel bookshelf model (all around $1,000/pair), measured as the most linear of the three and was the reviewer’s personal pick over both, despite the Dynaudio’s deeper bass and higher output capability. Independent ASR Klippel measurements corroborate Erin’s findings: superb off-axis response with only slight on-axis variations, and an in-room response the reviewer called “incredibly smooth and accurate - amazing for a non-DSP speaker.” Distortion above 200Hz at 86dB/1m is very low for the class.
Cons: F3 of 55Hz and F10 of 39Hz mean in-room extension tops out in the mid-40s Hz; the reviewer still recommends a subwoofer for full-range material. Diffraction dips appear around 3kHz and 5-6kHz, and the 1” dome tweeter starts beaming above roughly 6.7kHz, narrowing the soundstage radiation in the top octave - a straightforward consequence of dome size rather than a design flaw. At 96dB/1m the 5.25” midwoofer shows increased distortion in the midrange, likely tied to motor topology; high-passing to a subwoofer around 80Hz largely clears it up. Moderate sensitivity (~81-82dB average) with a 7-ohm minimum impedance. ASR’s power-sweep testing found response holds steady up to 96dB SPL/1m, but pushing to 102dB causes midbass below 400Hz to sag with distortion “through the roof” - a harder output ceiling than the 96dB tests alone suggest. Vertical directivity also narrows above about 1kHz, so the reviewer recommends staying at tweeter-axis height for best results.
Full Ascend Sierra 1 v2 review and specifications →
| Bass Extension (-10dB) | 39Hz (measured, Erin's Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 55Hz (measured, Erin's Audio Corner) |
| Dimensions | 14.2"H x 7.5"W x 10.5"D (361.9 x 190.5 x 266.7 mm) |
| Drivers | 5.25" proprietary mineral-filled polypropylene cone with cast aluminum frame woofer, 26mm aluminum/magnesium alloy dome tweeter with titanium former (SEAS Titan) |
| Impedance | 8 ohms nominal, 7 ohms minimum (measured, Erin's Audio Corner) |
| Sensitivity | 81.5dB (measured, Erin's Audio Corner) |
| Weight | 18.5 lbs / 8.4 kg each |
| Woofer Cabinet | ported |
- Links
- Reviews, Comparisons and Sound Samples
- Erin’s Audio Corner: NEW! Ascend Acoustics Sierra-1 V2 Review More from Erin’s Audio Corner →
- Erin’s Audio Corner Website Ascend Sierra 1 v2
- Audio Science Review Ascend Sierra 1 v2 More from Audio Science Review →
- Erin’s Audio Corner: 5 AWESOME SPEAKERS Under $1000 You Won’t Regret
- Erin’s Audio Corner: I Tested 250 Speakers So You Don’t Have To!
- Erin’s Audio Corner: My Top Picks of 2023: Must-Haves Under $3000
- Manufacturer Measurements (spinorama.org)
- Reddit Search for Ascend Sierra 1 v2 Review
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