Since getting back into biking with the Speed Twin, I'm slowly trying out some new things. Dart Classic screen is ordered and I'll report back on that once I've given it a few runs. Today's revelation though are the Bose QC20i headphones, which I've just used on the way home from work. Helmet is a Schuberth C3 Basic and as I mentioned above, no screen yet. I tried a variety of roads, from lanes to motorway and speeds up to whatever 4000rpm equals. Probably around 75mph indicated. They were plugged directly into my iPhone, which is mounted on a Quadlock. Wind sound was almost non-existent at all speeds, and other sounds were damped nicely. I could hear a car horn which beeped another car on a roundabout. I had some music playing at a comfortable volume. It was clear to hear and sounded as good as you could reasonably expect. Wind noise did increase when I opened the visor at slow speeds, but worked best when it was shut. Head and chin vents were open throughout. I experienced no popping (as others have reported). Although clumsy with the cable setup, this will be my go-to config for longer rides. Next time I'll try plugging it into the Cardo, which will hopefully be a further improvement.
Thanks I'm looking for some earphones with noise cancelling. At the moment if I want to listen to music it's on near full volume and my ears are ringing after my commute! Edit: Just seen the price, ouch!