What was the first system you heard that made you think the high end made sense


I am sure I cannot be the only person here who can recall the day, and indeed the very system that made them think 'oooohhhhh yesssss - I get it - I understand - and I absolutely love it!'

In my case I attended a HiFi Show in Heathrow at the Renaissance Hotel. It was the GT Audio room hosted by Graham Tricker. The parts comprised:

DPS turntable- Schroeder arm - jan allaerts cartridge
Tron Pre-amp
Avante Garde Uno's

In all honesty I still remember the day now. It was so musical and had the ability to connect me to the music. When I went for a full demo at Grahams home I came to understand the magic of horns, valves and imaging. 

lohanimal
Winter of 1970. Shacked up at a girl's house for a couple of weeks and she had in her living room a tube Fisher receiver and a pair of KLH speaker's. The sound had a very silky ultra smooth midrange that would stop you dead in your tracks. That got me hooked. One thing I will never get is this. When Henry Kloss left KLH and started Advent in 1968, his Advent design's were inferior to his KLH model's, especially the three way KLH model with its electrostatic tweeter that was the best model, and best sounding speaker him and his design team ever produced from 1964. I had a large pair of Advent's from 1976, which had much better bass slam than his previous KLH model's but the mid-range and high frequencies were no match against KLH. The Advent's were harder sounding and lacked the top end smoothness of KLH.
Marantz tuner, Garrard TT, and Superscope speakers circa 1977. My very first and favorite set-up. Wish I still had it. 
My late friend Courtney Carroll got me into audio way back in 1979-1980. He sat down with me and before listening for the first time we smoked some Colombian and it was on! I still remember that system. He had an ARC preamp and amplifier, Tympani 1D’s panels and using Mogami speaker cable. I have been into audio since that experience. ;)

My pivotal experience was as a child in the late 50s, listening to my parents 78 records on a monophonic console system with built in phonograph and radio of course. 

I would lie on the floor with my head centered under the only speaker and listen to record after record.  I didn't become a gear junkie until I started earning money and reading the mail order supply mags.  I've been upgrading that experience ever since only to be basically "done" now as I hit retirement. 

The systems I bought started in late high school, followed by a number of incremental changes over the span of many decades.  My current system starting from scratch once again, has taken about 6 years to sound the way I've always wanted.  Barring component failure or my life cut short, this should be my longest held system.  I seek nothing further at this point other than adding to my music collection.