On May 3, 1972 I saw the most amazing show of my life. It was a few years post-Woodstock, we'd lost Hendrix, Joplin, Morrison, and you could feel this special generational music, sounds that brought together a culture, going commercial. There were syrupy bands like America, "soft-rock" was a thing, and your mom and dad could actually like what you heard. Imagine your parents invading into your clubhouse. One group that the older generation thankfully would not understand was Pink Floyd who at this point was considered a weird band with a following of freaks and geeks. They had not yet become the "classic rock" band they've become known as. The band was quite English, which always seemed exotic. Their words were playful and imaginary and they often made music sans melody that veered toward noise, something to listen to in headphones rather than on arena stages, something that went against the grain of what rock was becoming.

The D.C. venue where I saw Pink Floyd play, The Kennedy Center, was where mom and dad would dress up in tux and gown and stroll down the red carpets to see opera, the National Symphony Orchestra, Leonard Bernstein's Mass. But on this spring night, only nine years since Kennedy was assassinated, only months after the posh palace on the Potomac that bore his name opened, my heroes of the psychedelic underground came to play. They filled the Concert Hall with around 2,000 hippies in torn blue jeans — like myself. Being in the space that night felt like a big middle finger to the rich and powerful.

I'm going to say that most everyone in the concert hall that night was high. Concerts back then were a huge, still somewhat rare event. When they did happen, they often took place in sports arenas that made the music sound boomy and bad.

This was my first Pink Floyd show and my first show at The Kennedy Center. I went with some of my coworkers from Waxie Maxie's, the record store I worked at in Rockville, Md. One of the wonderful things about working in a record store was that we always listened to and argued about music. The crew I was with spent had many hours cranking Pink Floyd's then-seven-month-old album Meddle, which featured the insane, out-of-this-world 23-minute journey known as "Echoes." The idea of seeing this performed live was just a staggering thought that I carried with me as I found my seat.

When the band, then Roger Waters (bass, maybe acoustic guitar, lead vocal), Rick Wright (organ, piano) , Nick Mason (drums, gongs and more) and David Gilmour (guitar, lead vocals) began to play, my ears heard music in ways I never knew was possible.

It was as we'd say back then, "a rush." When the band played "Careful With That Axe, Eugene," from the beautifully bizarre and frightening double-album Ummagumma, flames fumed around the gong of drummer Nick Mason. I'd never seen pyrotechnics at a show before, and the moment made the hair on the back of my neck stand up like I'd never felt before. I remember turning to my friend Kevin and seeing his wide red eyes — we were both exhilarated. Then they played the tune we'd all come to hear, "Echoes." Gilmour's slide guitar was out of this world. Simply astonishing.

Memory can be twisted and tough to recall given that it's been 45 years and given my state of mind, but I seem to remember a break in the show here. If the concert's first half was everything I'd been waiting for, what happened after the break would alter how I would think about music forever. Pink Floyd began to play music none of us knew. The hyper real sounds of alarm clocks, heart beats and cash registers turned into rhythms. What they were playing was billed as Eclipse: A Piece For Assorted Lunatics. Lyrics were printed in the program for a song called "Breathe," so poignant to the 18-year-old kid I was:

For long you live and high you fly

And smiles you'll give and tears you'll cry

And all your touch and all you see

Is all your life will ever be

What unfolded over the next 45 or so minutes was music like no other.

My friends and I walked out of The Kennedy Center flabbergasted. The sound system in the room was stunning. The band employed a 360 degree sound system — something unheard of at a time of lousy live sound. We witnessed music with mystery and meaning filled with adventure and surprise.

What was that music? When would we be able to hear it again? In the days before immediate access to media, even a bunch of music-savvy fans all working in the music world couldn't find out what this music was and when it was coming out. A month later, there was a new Pink Floyd album, Obscured By Clouds, and though it did contain that bit of instrumental music we had heard as The Kennedy Center show opened, it wasn't the Pink Floyd album we were waiting for. It wasn't the 45-minute opus with the cash registers and heartbeats.

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