Relatively average
The helmet has a very nice look and feels solid. The cable can be completely detached from the headphones, which makes it easy to store. On the other hand, I find the sound very average for its price. The bass is present but the sound is very very far from being exceptional. It replaces my old 20€ headphones and I don't see any major difference in sound quality. The headphones are quite heavy and contrary to other reviews I find them uncomfortable over a long period of use. It's a good insulator from outside noise though. But overall I don't recommend it for its price.