I have now owned two Kohlerts, a Winnenden (1954) and a '57, and find them to be vastly different horns. The Winnenden looks very much like the contemporary "The Martin" horns (LH bell keyguard, rounded soldered toneholes) and has the same great flexibility of sound and effortless sound production of the Martin horns. I had one of these a while back, and it was absolutely wonderful to play. The sound was big and dark, and in this respect, the sound was darker than my The Martin tenor. The overtone series spoke incredibly well, and altissimo, which on most Selmer horns seems to thin out, seemed just to get stronger. I loved this horn, but the palm keys went sharp on it, so, very reluctantly, I let her go.
I then started looking for a '57, thinking that, since they have the rep of being the best Kohlerts (at least that's what saxpics said), the intonation issue I had with my Winnenden would be settled.
I did find a very nice one, bought it from Fred Hemke Jr., and indeed, the intonation is very good on this horn. But I find the horns are entirely different animals. I find the '57 to be perhaps more like a pre-1947 10M in playing character. It's got this still dark, but very thick and dense core sound, and plays with considerably more resistance. At first, I played it with my Link, and it played too stuffy. But when I went to a more free blowing piece, a red Vandoren 77, I found the right amount of total resistance and it just plays beautifully. I really am serious about the density of this sound though. Amazing. The altissimo is also very good on this horn. From the mechanical point of view, I'm sure the rolled tone holes and inside bell keys make quite a difference.
I still don't know if the '57 is my kind of horn. I prefer less resistant and more flexible horns, more Martin-style than Conn or Selmer style. But I am curious to see if other people see the two generations of horns as differently as I do.
Do you think the Winnendens and the '57s are entirely different animals?