The HE6s are an odd duck and not for everyone. That being said, I have been using them for over a year daily.
There are some things that you can do [which all probably been mentioned already] to make these headphones the most fun pair you've ever listened to.
1. Swap the grilles. This seller on eBay makes these honeycomb grilles that completely open the headphones. It is unbelievable how much they open up the soundstage. My other phone is an HD800s, so I know soundstage. I've been meaning to spray paint them yellow!
2. Get an 4-pin XLR to Spade Balanced Headphone Cable Speaker Tap Adapter. There used to be a guy on eBay that made them, but they disappeared, and probably not in a good way. Plug that sucker into your power amp, or even AV receiver, pre-amp it, and feel the power. Even cheap amps bring out so much in these headphones. "Ewww dirty power! What about noise??" well don't worry because these aren't very sensitive headphones. Even in my cheap 20yo Yamaha receiver I don't hear a hiss. Just be careful to not blow them.
3. Change your EQ profile. Feeding them directly into a speaker amp changes them into a completely different headphone. Adapt your EQ to suit the changes, and enjoy that 30-40hz sub-bass rumble around your skull. It is bonkers.
There are some things that you can do [which all probably been mentioned already] to make these headphones the most fun pair you've ever listened to.
1. Swap the grilles. This seller on eBay makes these honeycomb grilles that completely open the headphones. It is unbelievable how much they open up the soundstage. My other phone is an HD800s, so I know soundstage. I've been meaning to spray paint them yellow!
2. Get an 4-pin XLR to Spade Balanced Headphone Cable Speaker Tap Adapter. There used to be a guy on eBay that made them, but they disappeared, and probably not in a good way. Plug that sucker into your power amp, or even AV receiver, pre-amp it, and feel the power. Even cheap amps bring out so much in these headphones. "Ewww dirty power! What about noise??" well don't worry because these aren't very sensitive headphones. Even in my cheap 20yo Yamaha receiver I don't hear a hiss. Just be careful to not blow them.
3. Change your EQ profile. Feeding them directly into a speaker amp changes them into a completely different headphone. Adapt your EQ to suit the changes, and enjoy that 30-40hz sub-bass rumble around your skull. It is bonkers.