No one has disputed TH900 being "fun". I guess I'm really in the minority since many seem to associate EDM to huge bass with ear piercing treble (=fun music? eh). Not to mention how vague "electronic" or "EDM" can be anyway, not all even have bass..
When someone looks phones for IDM/EDM/rock/soundtracks without stating anything else about own preferences, I would hesitate recommending the expensive TH900 straight away. To me it sounds like a more neutral and open phone might be in order. Naturally that's just my preferences. Who knows, maybe TH600 would be nice, it would be fun to hear if it's a bit more neutral than it's big brother.
That^ I definitely don't agree with. I can't understand how anyone would think the TH-900 has HUGE bass, I'm guessing you've never heard some other bass emphasized headphones like the D2K, D5K, D7K, HE-400, Q-40, M-100, etc. All those headphones IMO have more bass quantity. Quality I would say not many compete with the TH-900. Also, you aren't the first to mention "piercing treble" but it is definitely rare to see. I don't get it. You profess that the HD800 is such as good all around headphone, maybe true, but are you not bothered by the HD800 treble which IMO is much more aggressive, and are bothered by the TH-900. It doesn't make much sense to me. Also, I would try the TH-900 with multiple sources and amps if you have the chance. I'm quite sensitive to harsh/piercing treble and I don't experience that with the TH-900 at all. Might be my gear, who knows.
Electronica is not really vague, it is a legitimate genre of music. Now, I understand under electronic music there are MANY sub-genres such as EDM, but there all share common characteristics. One of them being prominent bass. Bass is emphasized in electronic music, so naturally people would enjoy music that has emphasized bass with cans like TH-900 with its fast decay, impactful bass, and linear bass (i.e not as bloomy as the LCD-2). Obviously everyone has their own tastes, but for me the TH-900 bring "fun" every time I put them on, because of their unique sound signature. I listen to most of my phones equally depending on the genre I'm in the mood for. Personally I use: TH-900 for electronic and pop. LCD-3 for jazz, rock, classic rock, metal, progressive rock, etc. and the HD800 for more sophisticated music such as classical. I maybe the only one who thinks that shrill highs are not pleasant especially for electronic music, but I'm fine with that. The HD800 would be great I assume if it didn't have the peak in the treble region. I haven't played around with EQ, so I might change my opinion, but right now I feel you can get much better than the TH-900 for electronic music.
Sorry Sean, that was directed at Hekeli not you . I agree that the Sig DJs do a very good job at rendering electronic music specifically EDM. I can understand why some would tend to find the lushness of the TH-900 to be somewhat distracting or not suited for electronic music. I guess in this situation YMMV.