Yeah, the newer Senns sound dead. The sennheiser veil used to be lack of treble, but these donlt have upper mids too. Make sure you never buy current Apple headphones then, haha. They are HD6xx squared. One day I equalized my ear gain flat with my own ears and then listened to heaphones like this. It was awful, sounded like an ear infection.

That being said, if you read B&K occluded ear simulator patent, you'll see that there is a big variance in our ears. Some ears have a response that matches headphones like the 6xx. HD650 is matching the median very closely up to 6k and then drops a little. Many people complain that they're too hot, so it tells you something about neutrality.