I went to the W3 from the SE215 too at one point, and I was hugely disappointed. The jumps in resolution, clarity, soundstage, etc. are huge, but there is more midbass and less rumbly subbass in the W3 than the SE215. Also the mids (ie vocals, most instruments) are pretty much continuously overshadowed by the midbass punch; whether its an 808 drop or a kick drum, the W3 exaggerates the hell out of any kind of bass punch, but doesn't give up a nice, tactile rumble like the SE215; it's all punch. Also the W3 has positively PIERCING treble that exaggerates the shimmer on things like cymbals to a point that I personally found annoying, especially coming from the tame treble of the SE215. The one thing the W3 does REALLY REALLY well is sound separation and speed. Its hard to appreciate over the bloated midbass, but the W3 is ridiculously fast, probably more detailed than my SM3 and the soundstage is deep and tall, with an almost dissecting way of presenting the sound. Everything sounds really clean and dry, which really impressed me at first listen, but the treble was sibilant as all-get-out even with all different kinds of Complys, Shure olives, etc, and the midbass was just way too much for me; they approach Beats by Dre territory, to be frank, in terms of overshadowing mids and just sounding...bad.
The SM3 is much more similar to the SE215 in tonality: slightly warm but still clear, a bit darker than the SE215 but with much better treble. Don't expect SE215-like bass from any armature setup, though; BA bass is an entirely different kind of bass, even with the W3. But the SM3 has a nice, neutral bass quantity that I have found it easy to get used to, especially because they offer more of a nice reverb and bass extension than most BAs. They are still the king of my collection, even though the TF10s get more play time these days. The realism of their sound coming from a BA is just really, really impressive. I also looked at the SM2 but I am kind of glad I went straight for the flagship, to be honest. Personally I have removed the filters, which removes a bit of the veiled effect some people complain about with the SM3 (the sound is somewhat distanced with the filters due to the huge sound stage). With the filters gone, the bass is very extended, with decent, well-rounded impact and more rumble than I had dared hope for with a BA. I wouldn't call the mids sweet though, more like lush (with filters) and forward (even moreso around 1k-2k without filters). You really can't go wrong with the SM3, it's a freaking beautiful phone, and I'm sure it will do both of your genres well. The only possible catch is its presentation; coming from the SE215, it took me a while to get used to the way the SM3 presents sound, it sounded really strange at first and I didn't quite know what to think of it. But personally I was able to get used to the sound over time, and when you have the luxury to really sit back and let yourself soak into the music, the SM3 is really incredible. I can't use them as every-day phones just because they feel a bit too fragile and I don't want to throw away what is probably the only pair I will ever own, due to price
but they really are every bit as impressive as I was lead to believe they were.
If you want something less analytical, you could look at the Klipsch X10, or, if you're not too sensitive to treble, the TF10s. The mids on the TF10 are more like those of the SE215 than any BA phone I've heard; not lush like the X10 or SM3, but not too dry like the W3. They are not forward like the mids of the SE215 though, if anything they are SLIGHTLY recessed, but nowhere near so much as the W3. The treble is much more extended and very nice on the TF10, midbass punch is slightly less than SE215, its not as powerful in the low-lows either but the actual extension is better, if you listen closely. They definitely have even more fun-factor than the SE215 in my opinion, but it's a different sound overall. AWESOME for electronic music, though; I haven't heard anything better for Infected Mushroom and Shpongle, which is what I listen to the majority of the time. My unfiltered SM3 is a bit better for Juno Reactor though; Juno's stuff really pulls its details in the mids, which the unfiltered SM3 does better than anything I've heard, and the open stage really compliments some of Juno's more jungle-esque tracks.
The X10 is very lush in the mids and very extended in the bass. The overall tonality is similar to V-shaped phones, it has this nice kind of liquid-y feel in the way it uses its treble, not unlike the TF10, that I really enjoy, personally. Really nice bass for an armature, especially SINGLE armature. Really great isolation too, I used them on the train. Treble is not very extended but the sound is tonally balanced, not bright or dark. The mids are slightly warm but still clear, they don't get overshadowed by the bass. This was my first upgrade to the SE215 that I really enjoyed. It's a pretty safe bet because, like the TF10, it can be had for pretty cheap. It is very user-friendly as long as you either have ear-guides or don't wear them with clothing that can exacerbate microphonics, which I found a little annoying. Actually the reason I sold them was because I got frustrated with the microphonics when wearing a winter jacket and one day I just said "FUGGIT" and put them on the FS section...I wish I still had them though, I'd love to be able to do a comparison with SM3 and TF10. I think they actually have a combination of the tonal balance of the SM3 and TF10, but cant really touch either when it comes to soundstage. They are nice and fast though, and the bass is really great. Still one of my favorite phones, I have to remember to grab a pair while they are still in production.
I haven't heard them myself, but the SE535 might be what you are looking for. It's dangerous to go by FR graphs, but comparing the TF10 and SE535 on paper, the bass of the SE535 is much more linear and better extended. |joker| has noted that it is similar to the SM2/SM3 in presentation of bass and quantity: respectable quantity, with good extension, and a slightly softened impact. Forward mids will be good for your pop, and of course the 3BA soundstage does wonders for electronic music. I am really curious myself to try them, mostly to see how they stack up to my SM3
In short, the SM3 is hard to go wrong with, but there are definitely other options, especially if you don't want to spend that kind of money. Myself, I arrived at the SM3 and TF10 in the end, like I kind of knew I would, and they are both awesome
W3 was definitely the least worthy stop along the way, for me personally; the bass was just too much, definitely more than the SE215 in the midbass, and not very textured at all. Based on everything, I would say go for the X10 or SM3; maybe do the X10, enjoy them for a while, and leave the SM3 as a potential upgrade. I really enjoyed the X10 coming from the SE215; the BA sound takes a little to get used to, it will probably sound really weird at first, and a single BA will ease you on your way up to 3; the presentation of triple-driver IEMs varies from IEM to IEM, but its a pretty weird process getting adjusted to the way they present sound, you have to pay more attention to appreciate the sonic qualities and especially the space, than you will be used to coming from dynamic IEMs.
But yeah, I think the X10 will do your two genres well, and will leave you a little room to upgrade (don't underestimate it though; it's definitely still a top-tier earphone IMO), but if you want to go straight for the top, go ahead and get SM3.
