The Talking Machine Forum — For All Antique Phonographs & Recordings

The outside diameter of the threaded part is just about ¾". I'm positive your horn is for a front mount machine-- The horn that was attached to my elbow was totally smashed/destroyed, so it was trashed. It was a 30" horn like the set up I had seen on an AY.
Columbia also used a built-in brass elbow (much like Zonophone horns) for the AY/AR. When I was putting together an AY a couple years ago, I purchased one of those horns from a gentleman in Florida-- At the time, I was told that only the AY/AR used the built-in elbow horn--- but again, I'm not a Columbia expert. I would assume that the screw-on aluminum elbow predates the built-in brass elbow. Anyone out there know??
Perhaps your 18" horn would have been used on an early AJ or AK?? We need a Columbia collector to add some info here-- Thanks!
Brad

Just another bit of info-- I just re-read your last post, and your mention of the 18" upgrade horn mentioned in the Columbia cylinder book-- I've had two of the 18" horns over the years-- both had the horn hanger and the nipple was not threaded. I'm confident that what you have was made specifically for a front mount disc machine. Where's Hazlecorn on this? Howard???

The small end on that horn looks like a standard ⅝" diameter, correct? If so, a ¾ thread elbow won't fit.

Another observation is the poor seam welds. Looks like this could have been a standard horn at one time that was modified for some other use.