Bose QuietComfort Ultra Headphones vs Sennheiser HD 505

Bose QuietComfort Ultra Headphones

Premium build and excellent comfort, though slightly heavier than the previous generation.

• These are incredibly comfortable for multi-hour listening sessions — the protein leather earpads are plush.
• They're noticeably heavier than the QC45 — I felt it after 3+ hours of continuous wear.

Sennheiser HD 505

The HD 505 reuses the proven HD 500-series chassis: a featherlight 237g frame, cushy earpads and gentle clamp that make it one of the most comfortable open-backs in its class. The trade-off is a functional plastic build that doesn't feel premium.

• Refreshingly light at 237g without the cable, with solid (if not premium) build and cushy earpads.
• It largely sticks to the HD 500 series' tried-and-tested design, keeping it compatible with first- and third-party accessories.
• Lighter and gentler than the HD 600 — it has the least clamp pressure on the table and is more comfortable than the rest.
• In a minor upset, the HD 505 is more comfortable than the HD 600 thanks to slightly gentler headband compression plus its lighter 237g weight versus 260g.
• The softer earpads give a better seal for larger ears and glasses wearers, though that matters less on an open-back.
• Some buyers may expect a more premium, metal-heavy build at this price — the build feels more plastic than premium.
• Reviewers ding Sennheiser's HD 5xx naming convention as confusing, even as the headphone itself is well liked.
• Owners note the same earpads carry across the 5xx models and aftermarket pads fit, though OEM pads are softer and insulate slightly better.