(...) I probably have owned at least 7-8 pairs of Quads, 2 pair of which have been ESL 63s. There's no question that the mid range is what its all about with Quads. My last foray into Quad Land was owning a pair of stacked ELSs with Decca Tweeters mounted in the middle of each stack and 2 Hartley subwoofers built into the back wall. All of this was tied together with a Mark Levinson LNC-2 Crossover. Keeping everything running in top shape in that system (including frequently replacing blown out dust covers on the Quads) was a little like owning a very exotic, high performance, antique car that we built from a kit. It took 25-50 watts to drive the speakers and 55 watts to blow them up! The sweet little hot amps we used were always ready to fall off the knife edge, too. Exciting times!
You are dedicated!
Well, I owned 3 pairs of ESL57 and 5 pairs of ESL63 - still onwing 3 pairs of the ESL63. Curiously my exposition to Quad's was in the opposite order of yours - the first time I listened to them was helping a friend assembling his HQD Hartley-Quad-Decca system with the LNC-2 crossovers (100 and 7000Hz, I still remember). Curiously last week I learned the same Hartley 24" drivers are now for sale nearby.
Later I went into single ESL57 pairs and got one the first ESL63 to leave the UK in 1981. Since then it was a relation of come and go ...
Retrospectively, the ESL's 63 system that was more emotionally engaging (to use the WBF lexicon) included an Audio Research LS5mk3 - VT150 monoblocks , a Forsell CD player combo and all Transparent Audio Reference XL cables. A short experience with four ESL63's used in a double L arrangement (one pair is used normal to speaker plane as a subwoofer, as used in the famous SME listening room) was extremely successful but not compatible with a family living room at that time ... But I hope to reassemble such complex system, with the SME improvements, sometime next year in a new space!
BTW, the sweet little hot amps were Bedini's or Electrocompaniet's?