horncups.com

Hi
I want this forum to remain as I while away many hours looking at it..........

Being a bit of a geek who keeps changing instruments one thing I have noticed is that any Medium bore horns I have owned (including Alex 90, Yamaha 667V, Reynolds Pottag) work best with a medium cup and open throated mouthpiece (PHC 23). However when I use a larger bore horn (formerly a Texas 8D and now a Reynolds Chambers) the 23 doesn't work well at all and produces a flat top register and with the Reynolds a very flat region around 3rd space C. On the larger bore horns going to a deeper cup (25) which should, I believe, actually make the high register flatter and harder work, actually has exactly the opposite effect - and the slightly increased resistance of the 25A cup really makes the horn work well in all registers and remedies the tuning issues.
This seems rather counter intuitive to me and wonder if anyone has any views.

Before PHC mouthpieces existed I was using a modified Giardinelli Chambers cup with a #1 bore (5.20mm) and thought that if Chambers could play a deep cup Giardinelli C1 then I should be OK using the same shaped cup on 2nd horn on my Kruspe and later Conn 8D. The PHC 25 cup (or Halstead-Paxman-Chidell cup as it was in 1971) was based on the C1 but with more metal around the cup to allow for our wider internal diameter of 18.50mm.

Players like Jeff Bryant were playing PHC 25 cups at that time on Kruspe and Conn horns. You obviously have a good, strong embouchure set-up so if it works then do it. The 25A followed a little while later for the reason you have mentioned. The 25A is the cup Tony Halstead favours now even though he designed the 24 cup and I designed the 25. Hey Ho.