Posted by CK on March 04, 2002 at 18:24:44:
I enlarged the throat on my old Helleberg. It took a little while going up in sizes gradually but got it to 23/64 and it has absolutely made a huge difference in the way in plays in all registers. I kept trying it out each size as I made it larger and love this throat size.
It is about the same size as the Elliott T6 shank or as close as I could find or make it.
Anyway if you have an old Conn Helleberg that you want to play with try it. It made a huge difference in all registers and the sound is warmer now too with a lot of punch. It made B natural really easy to play solid at volume.
Good Luck