Well, let me put it this way I follow this sub daily for years and I have yet to see someone have build quality issues with their HD6xx. People talk hypothetically that the build is plastic and so must be weak, but reality tells a different story. I’m far from a Sennheiser fanboy but undeniably the 6x0 series are maybe the best built hifi headphones out there just judging by the amount of issues people report with them, especially taking into account how widely used they are.

I’d say the 6XX is the best built 600 model out right now. The 6XX uses the old plastic mold, which is the same one that lasts decades. There’s still old 600s and 650s from the old mold that have lasted all this time, and have a reputation for their durability.

The current 600 and 650 models have a new mold which is more angular, but also uses thinner plastics. Going from my 6XX to a modern 600 felt like the 600 was way cheaper built and lighter (although I’m sure it’s still durable)

The plastics on them are lower quality than even the new 600’s, all to get that $200 price tag

They are well built it’s all plastic but good durable plastic the plastic on 6xx feels a little cheap but it’s high quality and durable. Any of 6x0 will be very durable and long lasting.

It’s not badly built, just a different material. Hifiman cans use metal parts, yet you can argue that they have worse build quality than Senns.

IMO well-built plastic cans are better than badly built metal cans by a long shot, as it is also lighter as a result, more comfortable for longer use cases.

well it feels like cheap plastic, but that cheap plastic is lightweight and rarely breaks.

Pretty much how the entire 6 line are built

Nah, it’s pretty nice actually