Sennheiser HD 660S2
Over-ear · 2023
Bose QuietComfort Ultra 2
World-class ANC · 30hr · Immersive Audio
Bose QuietComfort Ultra 2 takes it — here’s why.
In our weighted Specdex score, Sennheiser HD 660S2 lands at 92 and Bose QuietComfort Ultra 2 at 93. That puts Bose QuietComfort Ultra 2 ahead by 1 points — a narrow margin driven mostly by its strengths in the categories below.
Pick Sennheiser HD 660S2 if…
- ✓Flagship comfort + ANC on modern models
- ✓Premium build
- ✓Active noise cancellation (most models)
Pick Bose QuietComfort Ultra 2 if…
- ✓Deepest ANC on the market
- ✓Comfortable for 8hr+ flights
- ✓Bose Immersive Audio
Winner by scenario
Derived from the sub-score breakdown · not a separate testSound quality
Sennheiser HD 660S2Tuning, detail, and staging
Sennheiser HD 660S2 leads on sound (92 vs 90).
Noise cancelling
Bose QuietComfort Ultra 2ANC strength for commute and travel
Bose QuietComfort Ultra 2 leads on anc (100 vs 90).
Comfort
Bose QuietComfort Ultra 2Long-session wearability
Bose QuietComfort Ultra 2 leads on comfort (96 vs 91).
Value for money
Bose QuietComfort Ultra 2Specdex score per dollar at MSRP
Bose QuietComfort Ultra 2 more score per dollar ($449 vs $599).
Score breakdown
Specs side-by-side
| Spec | Sennheiser HD 660S2 | Bose QuietComfort Ultra 2 |
|---|---|---|
| Type | Over-ear | — |
| Release year | 2023 | — |
| Driver | — | 35 mm |
| ANC | — | Hybrid · 8-mic |
| Bluetooth | — | 5.3 + Snapdragon Sound |
| Codecs | — | aptX Adaptive + AAC + SBC |
| Battery | — | 30 hr (24 with ANC) |
| Charging | — | USB-C, 15-min for 2.5hr |
| Weight | — | 254 g |
Sennheiser HD 660S2
- +Flagship comfort + ANC on modern models
- +Premium build
- +Active noise cancellation (most models)
- −Battery varies by codec
- −Some are Bluetooth-only
- −Price creep vs previous gen
Bose QuietComfort Ultra 2
- +Deepest ANC on the market
- +Comfortable for 8hr+ flights
- +Bose Immersive Audio
- −No multi-point with 2025 firmware bug
- −Cable not included
- −Pricier than XM6
FAQ: Sennheiser HD 660S2 vs Bose QuietComfort Ultra 2
Which is better, Sennheiser HD 660S2 or Bose QuietComfort Ultra 2? +
Bose QuietComfort Ultra 2 scores 93 on our weighted rubric — ahead by 1. Your best pick depends on the sub-scores above.
Is Sennheiser HD 660S2 worth the price? +
At $599, Sennheiser HD 660S2 delivers a Specdex score of 92 — strongest in sound.
Is Bose QuietComfort Ultra 2 worth the price? +
At $449, Bose QuietComfort Ultra 2 delivers a Specdex score of 93 — strongest in anc.
Does Sennheiser HD 660S2 or Bose QuietComfort Ultra 2 last longer? +
Based on our long-term update and support ratings, both ship with multi-year support. Battery and reliability scores are visible in the breakdown above.
Which is better for sound quality, Sennheiser HD 660S2 or Bose QuietComfort Ultra 2? +
Sennheiser HD 660S2 — leads on sound (92 vs 90). Tuning, detail, and staging.
Which is better for noise cancelling, Sennheiser HD 660S2 or Bose QuietComfort Ultra 2? +
Bose QuietComfort Ultra 2 — leads on anc (100 vs 90). ANC strength for commute and travel.