How do I know it'll be good?

[Galliardist]

I agree with the first part of this statement. The shape of the ear (or more correctly, the absence thereof) will have more effect on the sound of an IEM than a full-sized over-ear headphone though, imho.

How well and reliably a headphone seals around your ear is also important, particularly with closed-back over-ear headphones... If you want a more consistent sound each time you listen to them.

The shape of the ear and the seal are at least related for my ears - I have big ears and deep lobes...

 

[ADU]

Well, lucky me my ears are REALLY average like if you ask someone to draw an ear, that's mine. For my headphone choice, I already committed to the Hifiman edition XS, and I'm sparing for the Fiio K9 pro to replace my amp. Still wondering if the K9 pro isn't a bit too much but that amp is universally acclaimed and doesn't cost an arm and a leg.

Can't really offer any advice on the Fiio, since I've never used one. Your comment above about it being universally acclaimed sort of begs the question though... for what? Is it the sound quality, features, connections, portability, or maybe something else?

Again, I'm not that familiar with the Fiio product line, so I don't really know much about them.

My biggest problem is for the speaker and speaker amp that are quite the nightmare to figure out and as said by @LTig , there's a ton to learn to be able to choose confidenlty.

Maybe yes. And maybe no. Like anything else, audio enthusiasts sort of have their own language, and shorthand for alot of stuff. Which can be a little intimidating at first. Most people are more than willing to lend a hand though, when asked. And the basics of a good stereo speaker setup aren't really all that complicated... Unless you want them to be.

Rather than diving in headfirst with alot of different gear, my advice would be to start simple. And then build out from there. There are alot of folks who don't have the discipline for that though. And want all the bells and whistles from the get go. Which is fine too, I guess. If you have the wherewithal for that.

 

[Galliardist]

And the basics of a good stereo speaker setup aren't really all that complicated... Unless you want them to be.

A big audiophile thing is to try one's hardest to get "the best" and something "musical" rather than aim for the better target of something that actually works. That applies whether you try to do things by subjective listening/upgrading (the road to doom), or by trying to find the "best" speaker and optimise it to the nth degree as people here seem to want to do.

You can get a lot of the way there without adding EQ, for example (and adding EQ to an already decent system will beat trying to use it to fix your previous mistakes). Get the room to a reasonably dead state, buy appropriate speakers, and if those speakers are passive get an amp that will absolutely, definitely drive them to high levels - even if you listen at lower volume - and you're probably already way ahead of what us oldies had when we started out.

Then find out about EQ and get the extra mile when you understand it.

 

[Gringoaudio1]

Nothing lasts forever though my dad’s old Heathkit Reciever did! You will undoubtedly be forced to replace or upgrade several times in your life. I’m 40 years into audio(63) and my first gear is an ancient memory. Get something, enjoy it and listen to music. The music comes first.

 

[Bsmooth]

Find a good brick and mortar audio store, and go in and ask questions, and listen. talk to others that come in and the people who run it, and listen. In a lot of ways its not much different than Photography, except with that its just take more photos.
Your first "good " system will not be your last. But all the components interact in that system, some for better some maybe not as well.
Use good source material, and find favorites you can take with you. Speakers all sound different, so you want a standard to judge those different speakers by.
Couldn't agree with the last poster more, the music comes first. Also it sounds easy, but learn to listen.