Sennheiser - HD 660S2 vs Master & Dynamic - MW75

These two are nearly even on the Mars Score (64.2 vs 67.1). The decision isn't about overall quality — both clear the bar — it's about which specific trade-offs fit your use.

Pick the HD 660S2 if you carry the device everywhere and weight or thickness has been the deciding factor before. The biggest gaps in its favor are weight, driver size.

Pick the MW75 if your top frustration with your current device is running out of charge before the day ends — endurance is the lead spec here. Its strongest claims are active noise cancellation, multipoint, battery life.

Both ship with comparable spatial audio, ldac, water resistance, so those specs don't separate the two — focus on the differences below.

Bottom line: there is no wrong answer here — match the spec advantages to how you actually use the product. The Mars Score parity tells you both are well-rounded; the differences are about trade-offs, not quality.