Real owners lean toward the Sennheiser HD 650: 75% of 316 owners recommend it, vs 45% of 469 for the Momentum 4 Wireless.
Verdicts aggregated from Reddit, enthusiast forums, and YouTube owner comments — affiliate reviews excluded. Sample sizes differ; judge accordingly. How we score
“What an incredible difference they make to everything I had before! You can listen to a track and hear subtle details that you did not even know they existed. Wow!”— @marco83 on YouTube
“HD650 with a bum driver, but I was able to solider the voice coil back on, so they work normally again. I had a pair 15 years ago and always regreted selling them.”— kindofbluetrains on Reddit
“I find the HiFiMan Sundara & the Fiio FT1 Pro both more useful for mixing - the Sennheisers have a much more condensed/flat sound with less bass extension than either of those”— @reallyoldcob on YouTube
Real owners lean toward the Sennheiser HD 650: 75% of 316 owners recommend it, vs 45% of 469 for the Momentum 4 Wireless.
Owners point the Sennheiser HD 650 at listeners wanting warm, non-fatiguing sound for long sessions, and vocal, acoustic, jazz, and classical lovers.
Owners point the Momentum 4 Wireless at sound-quality-first listeners who'll trade top-tier ANC for richer, fuller audio, and frequent travelers who want multi-day battery life and decent (not best) noise cancellation.
The most-cited downside of the Sennheiser HD 650 is rolled-off, light sub-bass that often needs EQ. For the Momentum 4 Wireless, it's aNC is consistently rated weaker than Sony (WH-1000XM3/4/5/6) and Bose competitors, usable for daily commuting but inadequate on planes for some owners.