Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Sennheiser - HD 660S2 | Bose - QuietComfort SC |
|---|---|---|
| Driver size | 42 mm | 35 mm |
| Weight | 260 g | 240 g |
| Active noise cancellation | false | true |
| Multipoint | false | true |
| Battery life | 0 h | 24 h |
Between the HD 660S2 and QuietComfort SC, the HD 660S2 comes out ahead in driver size, while the QuietComfort SC wins on weight / active noise cancellation. Overall, the HD 660S2 scores 52.5 and the QuietComfort SC scores 70.2 on our Mars Score.
Which should you buy?
The QuietComfort SC is the clear pick on raw spec strength, leading by 17.7 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the HD 660S2 if you care most about driver size. The biggest gaps in its favor are driver size. The single most decisive one: Driver size — 20.00% more. 42 mm vs 35 mm.
Pick the QuietComfort SC if you carry the device everywhere and weight or thickness has been the deciding factor before. Its strongest claims are weight, active noise cancellation, multipoint, among others. The single most decisive one: Weight — 20.00 g less. 240 vs 260.
Both ship with comparable spatial audio, ldac, water resistance, so those specs do not separate the two — focus on the differences below.
Bottom line: the QuietComfort SC is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Which should you buy: Sennheiser - HD 660S2 or Bose - QuietComfort SC?
Bose - QuietComfort SC leads the current Mars Score by 17.7 points.The more useful decision is the trade-off behind that result: compare driver size, battery life, weight against the way you will actually use the product.
Choose Sennheiser - HD 660S2 if…
Sennheiser - HD 660S2 has the measurable edge on driver size mm.
Choose Bose - QuietComfort SC if…
Bose - QuietComfort SC has the measurable edge on weight g, has anc, has multipoint.
This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.
Why Sennheiser - HD 660S2 wins
- ▲Driver size — 20.00% more. 42 mm vs 35 mm.
Why Bose - QuietComfort SC wins
- ▲Weight — 20.00 g less. 240 vs 260.
- ▲Has Active noise cancellation.
- ▲Has Multipoint.
- ▲Battery life: 24 h vs 0 h.
Spec comparison
Design
| Spec | Sennheiser - HD 660S2 | Bose - QuietComfort SC |
|---|---|---|
| Type | over-ear | over-ear |
| Weight | 260 g | 240 glead |
| Water resistance | none | none |
Audio
| Spec | Sennheiser - HD 660S2 | Bose - QuietComfort SC |
|---|---|---|
| Driver sizeⓘ | 42 mmlead | 35 mm |
| Impedanceⓘ | 300 Ωlead | 32 Ω |
| Sensitivityⓘ | 104 dBlead | 98 dB |
| Active noise cancellationⓘ | false | truelead |
| Transparency mode | false | truelead |
| Spatial audioⓘ | false | false |
Battery
| Spec | Sennheiser - HD 660S2 | Bose - QuietComfort SC |
|---|---|---|
| Battery lifeⓘ | 0 h | 24 hlead |
| Fast chargeⓘ | false | truelead |
Connectivity
| Spec | Sennheiser - HD 660S2 | Bose - QuietComfort SC |
|---|---|---|
| Bluetoothⓘ | 0 | 5.1lead |
| Multipointⓘ | false | truelead |
| 3.5mm jack | true | true |
| LDACⓘ | false | false |
| aptX HDⓘ | false | false |
Frequently asked
Which has better battery life, HD 660S2 or QuietComfort SC?+
QuietComfort SC lasts 24 hours vs 0 hours.
Do HD 660S2 or QuietComfort SC have active noise cancellation?+
QuietComfort SC has active noise cancellation; HD 660S2 does not.
Which supports LDAC, HD 660S2 or QuietComfort SC?+
Neither supports LDAC.