No.

I have a SB AE-5 > Modi >Valhalla 2 stack with HD800S, and HD660S.

There is a difference between the combinations (plugging into AE-5 directly vs Valhalla 2), most notably in the bass.

The biggest difference is the HD800S vs the HD660S. The HD800S straight up destroy the 660S. It's like sitting in a concert hall versus wearing headphones. Worth noting I literally grew up playing in concert halls, and have a trained ear (cello.)