Somewhere around 1967, Conn closed the Elkhart factory and moved elsewhere with new personnell (or something like that: this is the really- really short version).
The reason why the Elkhart-period instruments are such collectors-items is because some of them were exceptionally good. This refers to choice of material, consistency in harmonics, tuning, and especially: sound that some players could get. Mind-you: not all Elkhart instruments are as good: they had their ups&downs then as well. I own an Elkhart 88H (tenor) and have compared it against one modern version. Mine sings and all energy I put in pays itself out in stronger upper harmonics. So all energy I put in comes out as more brilliant sound. Doing that on the modern 88H takes a lot of effort and comes free on mine. That makes mine so valuable for anyone who needs to be heard over a 100-persons symfony orchestra going at fff. That is what makes it a collectors item.
As always: opinions of someone else might not work for you. If ever you get the chance to buy an Elkhart Conn, first try it out to see if it works for you. If a horn is still in reasonable state after 50 years, then it will very likely survive the next 10 as well.
Warrior92287:I'm fairly new to the basstrombone world and the only horn i've had time on is the Getzen 1052 FDR which i loved. I have seen on this site and a few others that alot of people are selling Conn Elkhart basstrombones. I am wondering if these are good horns since almost all the posts say that are from the 70s or 60s. Are these considered vintage horns? Can you use them in both classical and jazz? Will they hold up for a while?