IDEALregister holes

When we want to know where nodes and antinodes lie within the tube of the instrument, we use the method of the 'ideal register hole'. Such holes can, for different notes, in practice easily establish the position of the nodes.

An ideal register hole is a normal tone hole that is used as a register hole. Unlike the regular very small register holes – which can serve quite a range of notes – such large holes work correctly for only one or two notes, for which notes the hole is (almost) in the correct spot. In this way such holes determine the position of the wave within the tube. When a match is strikingly good, an exclamation mark is added. To establish the acoustical length of the upper register hole we need to remove the pip. Only in this way the hole acts more or less as a normal tone hole.
The table gives written pitch.

  A Bb B C C# D D# E F F# upper register hole
with pip removed


A. Sax sr. 195751415!17!1919/20
Conn Chu Berry12131616192021/2222
Buescher Truetone (curved)12131619192022
Buffet Crampon S1121316/1719/202122/2525C2/C#2


A. Sax sr. 2449512/1414/15151719202122
Buescher Truetone131416171920!22
A. Sax jr.121417192021/22C2/C#2
the Martin121417!1920!21C
YAS 2513/141617292022!(25)


A. Sax sr. 15676151719202122
Conn 10M13/14161719202122
Selmer mark612/1313/1416171920!21!22
Keilwerth SX90-R1314161719202122!25
Yanagisawa 90113/14171920!2122!25


A. Sax sr. 2250015171920
Buescher Aristocrat13/14161920/2122
The Martin Magna1213/141716!±192022
Selmer M612131619202122