My Quad ESL ownership experience encompasses two pairs of 57s, two pairs of 63s and a pair of 989s.
I therefore suppose I’m reasonably well qualified to answer your question, which probably doesn’t need to be much more than the fact that I’ve ended up back with a lovely, totally unspoilt 1978 pair of 57s. That probably tells you all you need to know.
Of course 57s are limited in terms of absolute dynamics, but I have a pair of Thiel CS 3.5s that alternate in my system with the ESLs. Between the two I’m completely happy and it’s huge fun to be able to enjoy either pair as and when the mood strikes. Right now I have the 57s in. They rotate with the Thiels every 3-4 weeks on average.
I endorse what others say here about the bass being underrated. But they do need several feet of clear space behind them to give a good account of themselves in that regard. Down to about 40hz you won’t hear more accurate bass anywhere.
The downside of ownership is that they do need a lot of TLC and a bit of servicing every so often. Mine have had a power supply rebuild, which addresses the most common long term issue. I’ve also had the clamps fitted as a precautionary measure.
While some enthusiasts take the view that the newer pairs offer a wider window of sound, the problem is that the 57 was a prime case of getting it right first time on terms of meeting Peter Walker’s goals. It took him one and a half decades to come up with the 63s, and the general consensus, which I also subscribe to, is that they lack that midrange magic that still seems elude all the other designs.
63s are a slightly easier domestic proposition, but since I’m lucky enough to have a dedicated music room these days, that’s a factor I thankfully don’t have to consider any more.
So having gone round the houses with various Quads, the 57s are the pair that will stay with me always, no doubt being refurbished as and when needed.
All that being said, I could easily live with the 63s and if the right pair ever presented itself at the right price, I wouldnt hesitate to own another pair in addition to the 57s. I just wouldnt replace them.
I’m running tubes with the Quads (VPI 299D) and I do think that’s the optimal route. However I also plan to get a Naim Nait 1 when the right one comes along as I’m curious to see how well that works. I’m also on the lookout for a really fabulous condition 33/303 combo.
If the classic British midrange is your goal, nothing will transport you there as wonderfully as 57s. I’ve owned LS3/5As and they go some of the way down that road. But the ESLs are the only horse in town if you want the full experience.
Good luck with whatever you decide to do. Neither model is a mistake.