[tenorblack]

On a tenor sax, generally how much space is optimum for the body octave pip to be vented when it is activated? Or in other words, how much space should there be between the pad that covers the pip hole and the pip itself when in the open position? What are the possible ill effects if there is not enough of a gap/ space there?

Thanks in advance.

 

[Captain Beeflat]

In air flow terms the pad should lift 29% of the hole diameter....ie. very little. However, no-one want to work to the lower limit. On most horns the lift is about 3mm to 6mm. That works perfectly well.
Usually the concern is whether the pad actually shuts rather than opens sufficiently.