Thanks for that insight Henry! & all these Bone-Yay horns play 'great' as variable as they present themselves... Even a later, nickel keywork ( some...
yamaha yas-52 alto
harwood c-melody
bright red bundy tenor
noblet tenor
International Woodwind IW-601-TSSP Tenor
1926 Holton silver plated bari
Dakota 600 Tenor (yani t-5 stencil I think)
and about 10 other horns.