I think if you're going in like "closed back = massive bass" you'd be disappointed. The extension is there for sure, but the FR doesn't have much / any bump. Mixes that are weak in the <100hz region are going to sound weak. Mixes that are strong there will sound strong, but not tooth-rattling.
Well
@Sennheiser you got the attention of Head-Fi.
Has anyone out there actually heard the HD820? I thought so.
Anyway, I don't think $2,400 is an uber price for a new flagship.
It competes well with the others mentioned...Focal, Audez'e and of course! HiFiMan.
Cheers All -
RCB
Actually I did get about 10 minutes with them last Friday, I can confirm they're not exactly bass-heavy. I didn't find any issues with the extension at all, but if you were hoping for a nice bump that a closed can often delivers, you won't really find it. It doesn't sound identical to the 800/s but it's not far off in gross tonality, IMHO. To put it another way, it seems sensible that they are close in model number and industrial design.
I should say, my overall impression was that they were really delightful for a closed design. If you were hoping this was when Sennheiser was going to develop a taste for pointedly elevated bass, I would say keep dreaming. Let's just say the sound is on-brand.
If you are hoping that this is a closed-back that sounds clean and spacious, almost on the level of a lot of open designs, this might be the ticket.
I didn't find any surprising "lack" of bass personally, but that's just one guy's opinion. If you are a basshead, steer clear, but you probably already knew that from the 800/s?
And I should caveat that all by saying I only listened for a period of minutes, my headphone testing pedigree is not in the same league as someone like Tyll, and I'm not even that familiar with the 800 line to begin with. I agree with people who are saying wait and see.