Whe you use headphones with a particular sound signature, your brain automatically adjusts to it, and a deviation from that will sound exaggerated. The XM4 is a really bassy headphone, it actually has more bass than even modern beats headphones.

If that's what you're used to, your brain will equalize to that so that sound signature sounds like a neutral to you.

The 560s has linear bass. Switching to that from an XM4 will make it sound like all the low end is missing, and it usually takes a few days of constant listening for your brain to readjust, then the bass will sound more full again and overall the sound signature will be fuller and you'll likely notice more details in music youre used to. After that happens, going back to the XM4 from the 560s will probably sound like the XM4 is really bloated and congested sounding, with much of the details in the mids masked