**** FLUTEKEY - Instructions and Notes ****

        The program FLUTEKEY permits the rapid calculation of certain 
parameters important to the design of the Boehm flute, or to the comparison 
of different instruments. The program shows the effects on intonation  
of varying these parameters. For a detailed discussion of the processes 
involved, see John W. Coltman, "Acoustical analysis of the Boehm Flute",   
J. Acoust. Soc. Am., V. 65 #2, pp 499-506, Feb 1979, or "Designing the 
Scale of the Boehm Flute", Woodwind Quarterly, February, 1994.

        Run the program by typing FLUTEKEY at the DOS prompt. After a few 
seconds the main menu will appear. This allows you to select the kind of 
flute being treated. After the selection, you will be asked to enter the 
bore diameter of the instrument in question. Then you may proceed to 
calculate the desired quantities.

(A) HOLE HEIGHT FROM DIMENSIONS  
       An open key on the flute can be characterized acoustically by a 
single number, the acoustical hole height "H". You will need this number 
to find out how changes in the hole or its position will affect intonation. 
Select item A on the menu to calculate "H" from measured dimensions of the 
hole and its key. Select the type of key (small, large solid, or perforated) 
and enter the dimensions (always in millimeters) as requested.  Key cup 
diameter is the outside diameter of the key that holds the pad. Chimney  
height is measured from the inner diameter of the main bore to the rim where 
the pad seats, at the point where this dimension is smallest. Key rise is not
measured at the outer edge but rather at the center line of the hole parallel
to the axis. This value is typically 2 mm on the C flute. Hole diameter is 
the i.d. 

        The program will not accept values that are too far from those that 
were used to create the program. In these cases you will get a message 
like "OUTSIDE LIMITS". Try a more reasonable value.  After the last entry, 
the value of "H" for this hole and key will be will be displayed. Two other 
quantities, "a" and "b" are also given.  These describe acoustically the 
cavity left when the key is closed.  FLUTEKEY does not treat these further, 
but they may be useful in procedures described in the references above.  

        Values obtained for "H" are valid for metal Boehm flutes. Wooden 
flutes or piccolos have a different geometry around the hole, and values 
of "H" will generally be higher. They are not treated here. 

HOLE NAMES.
        In the remaining parts of the program, you must specify which hole 
on the flute you are inquiring about.  * Important * The holes are named 
according to the system standardly used in the literature. Here the first 
open hole encountered in going down the flute, receives the name of the  
note it produces in the first register. The C# hole is the little one 
operated by the first finger, the C hole is the thumb hole, and the A hole 
is the one just above the lever operating the G# key. This differs from the 
system often used by flute teachers and flutemakers, which has many 
anomalies. In the system used here, if one wants to change the intonation 
of the note E, one works on the E hole.       

        The hole being worked on is defined by a number according to the 
diagram displayed on the screen, which imitates schematically the key 
arrangement on the flute. A number has been assigned to each hole on the 
diagram and is to be entered to designate the hole.  

       The diagram shows two C# holes for cases where an additional C# hole 
occurs on the flute.  For the conventional flute, use the upper one, #3. 



                                (1)

                                   



(B) DISTANCE TO COLUMN END. 
        This part of the program calculates the distance from the center 
of the hole to the plane where the the apparent acoustic end of the column 
lies.  This number is used in some calculations not incuded in this program. 

(C) HEIGHT OF HOLE - CHANGES.
        If one changes the height of a hole (for instance by substituting a 
perforated for a solid key) the pitch or frequency of the note will change.
Part (B) calculates the change in column length and the change in frequency 
(in cents) resulting from a change in H for any selected key.

(D) POSITION OF HOLE - CHANGES.
        A change in position of the hole will also result in a change in 
column length and frequency, which are calculated here.

(E) TRADE-OFF HEIGHT AND POSITION.
        If one changes the height of a hole, and wishes to keep the pitch 
unchanged, one can compensate by moving the hole position a distance  
calculated here. 


(F) Returns to main Menu.  Program may then be exited by choosing (6).


                                (end)