@PhotoJ Warm welcome to the community! I think you've already made your first "serious" purchase. The Senn. HD 5xx and 6xx line scale mezmerizingly well with expensive gear (meaning it sounds better depending on the amp you throw at it until seemingly no limit), and some people prefer these over other multi-thousand dollar flagship headphones. I'd say just bring your headphones and have fun seeing how astronomically different they perform with various amps / DACs.
I would definitely recommend waiting to upgrade until after you've been to one of these meets. Just being able to try gear out in person is worth years of reading, because you never know how something actually sounds until you try it. Each of us have our own sound signature preferences, meaning what sounds good to another may not sound good to you. The key is determining what your preferred signature is, so that you're able to find something that matches it. And once you spend enough time on Head-Fi, you'll learn how to know which members you can trust, based on things like popularity, similar preferences, etc. But in terms of a meet-up; the discoveries, friends and inside tips / tricks are really what makes it priceless.
Hang around these forums a while and you may be quite surprised at how deep the rabbit hole goes - other than hi-fi gear reviews, we also got threads for DIY custom cables & amps, tube rolling guides & discussions, electronic music, chances to talk with industry insiders, and even cooking!
EDIT: not to mention the guilty pleasure (that I think we all share) of reading the heated debates & drama that creeps up now & then... anyone have a funny argument they care the share about?
