Sorry everyone I made a bit of confusion with the word "fun", but I was thinking a simple word to explain what I'm looking for, so let me explain.
I recently bought a pair of Focal Elegia, because I own mostly open back headphones like Hd660s and Thieaudio phantom but also in the past nighthawks, hd600/6xx/58x, hifiman he4xx and fostex t50rp mkiii (after modded into Argon), but I wanted something close back with details, clarity and soundstage, but most important bass (that's why the word fun), and I knew from the brand Focal I couldn't go wrong (from all the nice headphones like Elex or Clear), but except clarity and details, the soundstage and bass lacks (maybe I should have bought another open back like the Elex or save the money).
I tried in the past when I start with headphones, the Sony mdr-1a which gave me headache from how much boomy bass had, really bad experience, so definitely no Beats.
I was looking in this days some reviews about the Meze99 classics, they're are really good looking with that wood, but they was saying that have boomy bass with not a lot of details, I hope they aren't like the Sony.
I had the nighthawks which was way too muffle with uncontrolled bass, but I read in this forum that the nightowl had fixed this problem, so that's why I put in my top picks.
Maybe like
serman005 says, 500 dollar it's too low, and I should wait for something like the ZMF Atticus.