programming with max/msp - Virtual Sound

Interlude A - Programming with Max/MSP IA
In this style of patch, the “cold” inlet of the addition object behaves as though
it were a “hot” inlet. Try building it, and verifying that the number box on the
right triggers a result every time that its value is changed.
It is essential that the positions of the objects in your patch are absolutely the
same as the positions in the figure. Placing the button to the right of the
+ object, for example, will produce undesired results, since the bang will fire
before the new value is stored, causing the addition object to use the old value
that had been copied into the internal variable previously in its calculation rather
than the new value (as shown in Figure IA.4).
Fig. IA.4 Buggy results produced by an error in the order of execution
Delete the two number boxes above the + object and connect a message box to
its left inlet. After this is done, type two numbers (separated by a space) inside
the message box, as in Figure IA.5:
Fig. IA.5 Summing a list
If you now click on the message box in performance mode, the + object will
sum its values; the operator behaves as though it had received the second
number on the right inlet (and, as usual, the argument 5 inside the object box
is replaced by that new value). This behavior (the ability to accept lists of two or
more elements on their left inlet and then route the individual list items to the
other inlets) is also a common feature of many Max objects, and works not only
with binary operators, but often with objects that have three or more inlets.
To see a simple musical application of Max’s addition object, open the file
IA_01_transposition.maxpat (seen in Figure IA.6). Every time a key is pressed
on the kslider object in this patch, two notes are generated, the second of
which is 7 semitones above the first – the musical distance of a fifth. Every time
that we press a key on the kslider, the value of the corresponding MIDI note
number (a C in Figure IA.6, for example) is sent to the mtof object on the left,
which converts it into a frequency value. At the same time, the note number
is also sent to a + object that adds 7 (producing the MIDI note number for a G
from “Electronic Music and Sound Design” Vol. 1 by Alessandro Cipriani and Maurizio Giri
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