I think the original Large Advent came out in 1971 & was & still is a good speaker. Stack them, remove the grill cloths , provide plenty of good power & you have a fairly ugly but nice sounding speaker w/ as good bass as probably any speaker made since up to at least $5K & maybe $10K. Mid range also pretty good but not much high frequency extension & mediocre imaging.
All Pre 1970 Vintage speakers suck! Prove me wrong
Have tried many vintage speakers.
My conclusion: All pre-1970 vintage speakers suck. Well-made but crappy sound.
Used with both vintage amps and modern.
I do like many vintage amps such as Radio Craftsmen RC-500, Marantz tube, Scott tube, Heath W5, Lafayette and Pilot tube.
But back to pre-1970 speakers:
No bass, harsh, or honky mids and no highs. Not musical or listenable to me.
Tried many including Acoustic Research AR-3a, 2Ax, etc. The entire AR product line. Also Klipsch Horn, Large EVs. Altec VOTT. Pioneer CS-88 and 99.
Nothing pre 1970 is even close to the better modern speakers.
I challenge you: Prove me wrong.