How do you get custom EQ on the iPhone?
Also, it's interesting that you mention the T1 because it is the neutrality and clarity of the T1 that I bought two months ago that is prompting my search for a replacement for the IE8. How do the W4 stack up against the T1, in your view?
I use an app called EQu. Basically just like the default music app but much better looking and with a whole host of EQ and custom settings. Highly recommend it.
http://itunes.apple.com/us/app/equ-the-quality-equalizer/id403704212?mt=8
The W4 has much more room for EQ'ing. It's sonic signature can be drastically changed with EQ'ing where the T1 is not as mouldable, which is fine given that the T1 pretty much already has a perfect balance (though maybe a tad sub bass shy for some). I say this after spending countless (I do mean countless lol) hours tweaking and EQ'ing, only to end up sticking to default or flat. You can't really change any element of the T1's balance without losing something special. For example, sure you can up the low end bass quantity, but you will lose some of the bass texture and bass detail. Like wise you can lessen the highs or upper band frequencies, but you'll lose the pin sharp imaging.
The W4 on the other hand, can be positively moulded with an EQ, since it's default balance is, imo far from perfect. It's a tad cloudy and timid, and just needs some tweaking to really bring the best out of it. But comparing my EQ tweaked W4 against an EQ tweaked SE535, W3, Triple.Fi etc, the W4 wins out due to it's amazingly wide (for an IEM) soundstage, and superior instrumental separation. With an EQ tweaked W4, you can detect more elements in music than with some of the other IEM's, though the others do excel in areas too, such as bass impact (SE535) and liveliness of sound (Triple.Fi).
So it really does boil down to personal taste and whether or not you'll be EQ'ing. If you're not going to be EQ'ing, and want something more fun and punchy, go SE535. Likewise, minus EQ'ing, if you want something nice and balanced, go UM3X. If you WILL be EQ'ing, and want something balanced and with fantastic clarity and separation (for an IEM), go W4.
With respect to the T1 vs W4 comparison. Firstly, there isn't much of a comparison really. The T1 is just a whole lot more detailed, dynamic and accurate. The W4 EQd has a bit more bass quantity, but not quite quality. The W4 also has a wider (sounds strange I know) at times, soundstage, but only horizontally speaking. The T1 has a much more three dimensional soundstage, where it's not just about figuring out sound placement width wise, but also in terms of depth and height. So you get a real sense of the entire stage a band is performing on, not necessarily, mainly the different sounds spread out horizontally, like with the W4. But this is a problem intrinsic to nearly all IEM's due to the design and nature of them.
So yes, the W4 is a highly accomplished IEM, post EQ, perhaps one of the, if not the best (Universal IEM speaking). But it's still not near the level of the T1 in terms of balance, three dimensional sound staging and imaging. For a more comparable IEM, you'd need to go custom, probably something like the ES5, JH13, JH16 etc. But I doubt even then, they'd be an exact match.
The W4 is more than enough for me on the move though. I've been thoroughly content with it coupled with the JDS cMoy. Though I wouldn't say no to upgrading if a new better product (universal only) came along. Like I said, Sony's new Universal IEM X3/X4 line look very tasty.