Not familiar with the *37 I actually have a REDD 47 I have built, two stage tube design...very high voltage based on the REDD 47...I may make a comparison...
On further inspection the REDD 37 is based on the V72 (I also have a Telefunken V672/2 which is currently needing to be recapped the *37 was based on the solid state V72)
So basically I can make a pretty accurate real time comparison using a U87 I also built (Dale-M single capsule) and that will get us in the ballpark of the original desk...
Not sure how Waves manages to do emulations...but they are normally closer than a hand grenade needs to be...at least on EQ's...
But when it comes to pre-amp emulation...I really wonder about tweaking something that never made it into the signal path to begin with...there is a certain non-linear element that transformers and tubes bring to the table...that was the whole reason I taught myself to build this stuff...it was cheaper than trying to tweak it into existence.
My pre-amps look nothing like the emulation though...but then again everything I have is now in racks except the Urei And Sony Desks I've rebuilt...(Sony Eq's are great... Urei is...Meh...)