First off, congrats on listening to absolutely the right genre of music!
As much as I love the SE846, I'm also a bit cautious about recommending them to you. Depending on whether you have a newer or older iPhone, you'll have either 1) silly dongles with a somewhat reduced dynamic range that connect to a proprietary digital port that doesn't always play nice with external USB devices, or 2) a HO impedance of about 5 Ohm, which is starting to get a bit high for the SE846. The SE846 has significant impedance swings with frequency, but is around 8 Ohm at 1 kHz. The iPhone can make it sound a little bass-heavy. (You may or may not like that.) But the MacBook is more of a problem. The SE846 easily shows up its noise floor (hiss).
I also have a MacBook and an iPad (I stopped buying iPhones when they ditched the headphone jack) and I understand how difficult it is once you're trapped in Apple's ecosystem. It's like smoking - just as insidious, just as bad for you and everyone around you, and equally difficult to quit. I don't think I'd recommend the SE846 unless you were also prepared to also buy something like a Dragonfly Red (or Black) or some other good-quality DAC that you could use with
both your Apple devices. (The MacBook will be the bigger problem with the SE846.) But you've said you don't want to use an amp or DAC - in which case, you might just be better off buying a higher-impedance IEM I would check out the excellent FLC8S (or the newer models FLC8N, FLC8D or Celeste that are coming out next month).
Good luck!