What are the best speakers you have ever owned and why?

I have had JBL L-100s for over 40 years. I have upgraded the crossover and they sound splendid. But as for accuracy my choice would be ATC. They come in all sizes and right down to the smallest bookshelf they will reproduce what is coming through the system, good or bad with no coloration.
Rollin

1970’s a pair of Martin speakers made in NJ - first revelation of what stereo sounds like.
1980’s Infinity RSM , was sorry the second I bougt them, way too dark sound.
last 15 years:
NHT the entire classsics range 1.5, 2.5, 2.9, 3.3.  , still most amazing value for a particular sound that I could easily live with.
Klipsch Heresy I, recd as gift, awakened me to the richness of horns. If they had better bass I would have kept them, now looking out for Forte’s that I think would settle second room needs.
martin Logan ESL, soothing mostly there music but just not exciting.
Egglestonworks Rosa, did everything right except deep bass
Egglestonworks Andra, maybe it’s my combo of Bryston pre/amp but I find that I am forcing myself to be happy.

i would love to hear Verity Parsifal’s, Gershman Swans, Legacy Aeris.

KLIPSCHORNS.......Nothing can top their "Full Tilt"   ""In your face"sound !!!

I found a pair of Legacy Audio Focus 20/20 at a reasonable price and they are the best speakers I have owned.  They create an enveloping soundstage and are detailed without being harsh and have no problem plumbing the depths.  I've had a lot of more "sophisticated" speakers, Vienna Acoustics, Canton, Spendor, Monitor Audio, etc. but the 20/20s just rock and are fun to listen to. 

I've also owned a lot of Klipsch speakers and my KLF-30's with Bob Crites crossovers, mids, and tweeters are my second favorite, more for sentimental reasons.  I remember early in my "audiophile" journey hearing some Klipsch RF-7 II and also some KLF-20 and being blown away by those.  I looked for the KLF-30s for a while and finally found a pair at a reasonable price and after spending some time fixing them up (I also had to fix rattling back panels), they are really musical.  A little "smoother" on the top end than some of the Heritage Klipsch like the La Scala (which hurts my ears at loud volumes).  They are very detailed and can play really loud without distortion or being "shouty" or "bright". 

I recently went through a similar journey with a pair of Klipsch Heresy I.  Replaced all the drivers and the crossovers and mated them to an ARC Vsi55.  The combination is very nice.

I guess I am an unsophisticated "meat and potatoes" kind of music lover.

My humble, 50 year, journey includes these as well as some KLH, AR or Infinity that I can’t really remember much about:

Lafayette Radio Electronics Minuets (excellent little bookshelf units)
Wharfdale W70 (room shaking bass)
Janzen Electrostatics (early ribbon tweeters - quirky electronics)
Ralph Vaughn - custom build (big woofers, mids and Janzen tweeters)
Paradigm Espirit Towers (my first eBay purchase)
KEF 105/2 (the "laid back" British sound)
Mirage OMD-15 (omnipolar; very holographic and sweet)
Joseph Audio Profile (neutral, clean and clear)