Bach Bells are very special in how differently they sound and perform. 25 Bell=Smallest flair, comes standard on LB Bachs. 37 Bell=Sweetest sounding bell, standard for years on ML Bachs. A little more flair than the 25. 43 Bell=Seems more projecting than the other bells, a LT 43 works great for Lead work. 72 Bell=Largest flair, seems more fullness and thickness to the sound. 38 Bell=Tighter than the others. I've only played one, a guy from the rodeo had one. Very bright. 65 Bell=Dark, lot's of lower overtones. I have a 72LT on my old LB Bach, got it after I heard Ernie Royal play! He played one and sounded magnificent! Bernie Glow had one as well. That's the sound I love. I also have a great 37 bell on a ML 43LR. Beautiful sound. Bach Bells are the best.