As an audio engineer using the LCD X for mixing, something I've noticed is that compared to the Sundara, which has been my reference headphone, the LCD X makes things easier to EQ. Makes decisions easier. Not hugely so, but it's noticeable to me. I think it's the way the X handles transients, maybe combined with the greater detail?? A common EQ trick to find problematic regions that need reduction is to create a filter and actually amplify those frequencies, sliding the filter left to right (up and down the frequency range). This makes problems more obvious, and then you reduce the offending frequency. Doing this on the Sundara was effective, but things didn't "pop" the same way they do on the LCD X. When I do the same technique with the LCD X, I'm just able to hear the effect much more clearly. I could boost things by 5db on the Sundara and would still be second guessing myself if I'm adjusting the correct frequency. On the LCD X, the effect of amplifying a frequency range is much more obvious to my ears, and then I can confidently decide which areas need to be reduced. There's more contrast, and my guess is that the LCD X is more resolving of detail in a way that makes transients come through very clearly. The Sundara is great, but things sound a bit more smeared.