@musicfan2349 -
Thought I was being pretty clear, but: the SP-11's signal path contains metalized, plastic film caps and wire-wound resistors, which (in my opinion) aren't, "vintage" parts. It does have some older-tech components, in the mix, which (to me) does put it on the cusp of vintage/modern.
No doubt: that pre could be warmed up quite a bit, with the right valves.
Basically, to me: the old Black Cat, paper/Mylar caps and Carbon comp resistors, in the signal path, were (largely) what gave the older gear (circa 60s/early 70s) the, "vintage" sound, some love so much.
The older ARC pieces had Black Cats, in their power supplies, which may have warmed them up, somewhat.
I owned both SP-9 and SP-14 pres, which I greatly enjoyed. Neither of which sounded like ARC's very early iterations. Especially with the early 60's, grey shield, Siemens CCa in play (my 6DJ8 variant of choice).
Still: from ARC's inception, the goal was to resurrect/reintroduce tube circuitry (transistors being the rage, then), with a cleaner presentation, than what was available with older tubed circuits (as I recall).
Don't know how ancient you are, but; being 75 years old: I suppose my views are somewhat different than later generations, far as, "vintage".
Like I said, "Just MY take:"
It's not my agenda, to change anyone else's opinions!
Happy listening!