Vandersteen 2c vs Thiel CS2

@beatle ya that would be the holy grail but then the ever restless and innovative Mr. Vandersteen would start polishing it.... I told this story on another thread - talking with Richard one day early in Covid shutdown - he was a work by himself - he said I have several changes I am making to the Model 2 to make it better - and now here we are !!!!! Since 1977

OP - fantastic that you have an SPL meter !!!
in addition to level matching- listen for hours - listener fatigue is real :-) enjoy your journey and as others have said share your travels and decision 

Thiels have very pronounced treble. That gives them great imaging, air, and soundstaging, but can make them hard to listen to. I finally built a low-pass filter to tame them.

@mike_in_nc
Can you kindly provide details of the low-pass filter?

@imhififan :  Regarding details of the low-pass filter, my regrets; it was too long ago, and I no longer have details. It was a simple R-C passive filter sketched out by a friend who knows electronics better than I. I assembled it into a little aluminum box, long gone.