This is a unique symbol identifying the instrument. It is used as a lookup value so that it may easily be specified in PART objects.

This is either a symbol or list of symbols, specifying valid clefs for the instrument in order of preference. The following clefs are supported: :bass, :c-baritone, :f-baritone, :tenor, :alto, :mezzosoprano, :soprano, :treble and :percussion. The user may also add an -8UP or -8DN suffix to the symbol to specify an octave transposition.

This is an integer specifying the number of staves to use. The default is 1.

This is an integer specifying the lowest pitch in the instrument's range. It may also be set to NIL, in which case the lower range is considered to be unlimited. This is only useful if the CHECK-RANGES setting is set to T.

This is an integer specifying the highest pitch in the instrument's range. It may also be set to NIL, in which case the upper range is considered to be unlimited. This is only useful if the CHECK-RANGES setting is set to T.

This is an integer of 1 or greater specifying the maximum number of simultaneous pitches allowed in a single voice. It may also be set to NIL, indicating that there is no limit.

This is set to the value NIL or an integer indicating the number of semitones to transpose the instrument before notating it. This number only has an effect if the TRANSPOSE setting is set to T.

The value of this slot influences how FOMUS decides when to change clefs. A clef change isn't considered necessary until the number of ledger lines required exceeds a threshold value. Other factors determine if there is actually a clef change or not. If the value is an integer, it designates the threshold number of ledger lines in all cases. If it's a list, the first element of the list must be an integer specifying a default threshold. This is followed by one or more exceptions, each in the form of a list. This exception list contains a clef symbol (see the CLEFS slot above) followed by one of the two symbols :UP or :DN and ended by an integer specifying the number of ledger lines. An example illustrates this data structure.

'(2 (:bass :up 3) (:tenor :down 3))
                

This value influences how FOMUS chooses where to place ottava brackets above the staff. An ottava bracket isn't considered necessary until the number of ledger lines required exceeds a threshold value. An integer in this slot indicates the threshold value, while a list of two elements specifies the threshold for the ottava bracket to begin and the threshold below which the number of ledger lines must drop for it to end.

This is the same as INSTR-8UPLEGLS above, only for ottava brackets placed below the staff

This is a list of symbols, PERC objects, numbers or lists indicating all of the percussion instruments that are to be notated together as a group. PERC objects provide necessary extra information for notating percussion. All of these value types function to lookup percussion instruments in the same way as the PART-INSTR slot of the PART class. Symbols are used as lookup values into a user-defined percussion instrument table (see the PERCUSSION setting) or FOMUS's own predefined table. Lists contain a symbol lookup value followed by keyword-argument pairs signifying values to replace in the predefined percussion table--it will usually be necessary to use a list instead of a symbol since the NOTE and VOICE slots are empty in FOMUS's table.

(list '(:low-tom :note 0 :voice 1) '(:high-tom :note 4 :voice 1)
      (make-perc :anvil :note -3 :voice 2 :midinote-ex 79))
                

This is a number from 0 to 127 or a list of such numbers specifying which MIDI program change values can translate to this instrument. This is used when specifying an instrument as a program change number (see the INSTR slot in the PART class) or calling the GET-MIDI-INSTR function. When given a program change number, FOMUS finds the first instrument that matches in its list.

This is usually a number from 0 to 127 specifying which program change value is to be used when exporting MIDI data. It can also be set to a list, the first element of which is the number mentioned above followed by keyword/value pairs indicating alternate program change values for different playing modes. (For example, the list '(40 :pizz 45) is a valid value for a violin instrument.) The keywords currently allowed are :PIZZ, :STOPPED, :OPEN and :HARMONIC. (More will be added in future releases.)