Great thread!
For me, it goes back to rock-radio back in the AOR days, with Rush being a primary influence, along with Pink Floyd, Blue Oyster Cult, etc.
I'll never forget when I went to the LaserDrive show at the planetarium in Atlanta, where they play music -- loudly! -- along with starscapes and laser imagery. Rush, Pink Floyd, Billy Thorpe....that was like a religious experience and I honestly think it cemented my interest in music for good.
Next musical milepost: Guns'n'Roses. Rock radio had become very 'safe' and banal in Atlanta, and then one day 96rock played G'n'R's "Paradise City" as their "smash or trash" song -- you call them and tell them if you liked it or not. The moment I heard the song and that it had done well, I thought "radio is about to change forever" -- and I was right. Several months later "Welcome to the Jungle" was released as a single. G'nR opened the door for hard rock and allowed Metallica to storm the radio scene, about a year later.
Sometime in 1987, the first person to join the fan-club I was now running for a British SF/fantasy author* sent me some stuff by bands from Seattle, where he hailed from. He specifically mentioned Queensryche and when
Operation: Mindcrime came out the following year, I was able to get it for free from 96rock as a contest prize.
I was floored. I even stopped the car on the side of the road in shock so I could hear it without noise. The album got me into 'progressive' metal, and since they were opening for Metallica, it's why I went to that particular show and, through a friend, met and befriended Kirk Hammett. QR and 'Tallica pretty much got me into the 'serious' metal scene for good.
Next milepost: hearing "Pull Me Under" on 96rock here, one of the 3 or 4 times it was actually played.
Loved the song, the drumming stood out particularly. I worked out a trade with a deejay friend at the radio station: I get him a CD copy of a rare 'Tallica song so he could copy it to broadcast cart (CD burning was still a few years away), he gets me some freebies -- including I&W on cassette, as they didn't have any promo CDs left. Same thing happened as with
Mindcrime: I stopped the car on the side of the road so I could hear it better. I was floored AGAIN.
I got involved with Dream Theater's online fandom, including the Ytsejam Mailing List, swiftly discovered bands like Superior and Symphony X, and became highly active in the more "underground" prog-metal scene.
Beginning in late 1993 or 1994 I had begun hanging out regularly at WREKage, the metal radio show in Atlanta (been running for between 25-30 years). By around 1998, the show's two then-student hosts were only playing brutal death and black-metal, and after some online complaints on Jim Raggi's forum -- from friends of the two students -- I was brought on-board to add more progressive metal to the mix. We jokingly called my segment "Paul's Progressive Patio."
--But along the way, a funny thing happened on the way to the forum: I began to really like some of the music I was intended to replace. I already liked, e.g., Opeth, but I began getting into other, more extreme metal bands, and nowadays I like extreme metal a bit more than other genres.
So, for me:
Rush/Pink Floyd/Billy Thorpe/BOC --> Guns'n'Roses --> Queensryche --> Metallica --> (Ozric Tentacles) / Dream Theater --> Opeth --> almost everything with talent.
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* Michael Moorcock; the international fan-club was called The Nomads of the TimeStreams. I ran it from c. 1987 through 1993 or so. Technically, Kirk Hammett, like me, is still a lifetime member.
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