17-2
FUNS
Programming the FUNs
between 0 and +1 as you push it up. When fully up, it sends a value that’s interpreted as +1. It 
can be used as a bipolar control source by assigning a value of Bi-Mwl to any control source 
parameter.
The Pitch Wheel is normally bipolar; it sends a control signal value that’s interpreted as 0 when 
it’s centered, values interpreted between 0 and -1 as it’s pulled downward, and values 
interpreted between 0 and +1 as it’s pushed upward. It can be used as a unipolar control source 
by assigning a value of AbsPwl to any control source parameter.
The FUNs can act as unipolar or bipolar control sources; it depends on the values of the input 
signals and the nature of the function you choose. Depending on the function you choose to 
process the input signals, the output signal value can exceed +1 or -1. Normally the signal 
merely pins at +1 or -1; that is, it won’t go any higher or lower. In some cases, however, the 
output signal value is wrapped around instead of pinning; we’ll mention these cases as we get 
to them. You can assume that the output signal values of the functions listed below will pin at -1 
or +1, unless specified otherwise.
Programming the FUNs
Start by entering the Program Editor, then use the soft buttons to select the FUN page. Setting up 
a FUN as a control source is a two-step process:  assigning a FUN as the value for one or more 
control source parameters in the Program Editor, then programming the FUN on the FUN page, 
by assigning control sources to two inputs—a and b, and choosing a function (equation) that 
will process the combined signals from Input a and Input b.
EditProg:FUN|||||||||||||||<>Layer:1/1||
||||||||||||||||||||||||||||||||||||||||
||||||Input|a:|Input|b:|Function:|||||||
FUN1:|OFF||||||OFF||||||a+b|||||||||||||
FUN2:|OFF||||||OFF||||||a-b|||||||||||||
FUN3:|OFF||||||OFF||||||(a+b)/2|||||||||
FUN4:|OFF||||||OFF||||||a/2+b|||||||||||
<more||LFO||||ASR||||FUN||||VTRIG||more>
There are four FUNS; you can combine and process four different pairs of control source signals. 
FUNs 1 and 3 are always local, that is, they affect each note in their respective layers 
independently. FUNs 2 and 4 are local by default, but they can be made global by setting a value 
of On for the Globals parameter on the COMMON page in the Program Editor. A global FUN 
affects all notes in its layer equally and simultaneously.
The best way to understand the use of the FUNs is to set up a simple test model, then plug in the 
different equations and listen to their effects. We’ll walk you through the programming of a 
FUN and assigning it to control pitch. Then you can scroll through the list of equations at your 
leisure.
Start in Program mode and select Program 199. Press Edit to enter the Program Editor. Select the 
KEYMAP page, and change the keymap to 152 Dull Sawtooth. Then select the PITCH page, and 
assign a value of FUN1 for the Src1 parameter (a shortcut is to press 1, 1, 2, Enter on the 
alphanumeric pad). Select the Depth parameter and change the value to 1200 cents. Next, select 
the FUN page, and select the Input a parameter for FUN1. Assign a value of MWheel (the 
quickest way is to hold the K2661’s Enter button and move your MIDI controller’s Mod Wheel). 
Next, select the Input b parameter for FUN1, and assign a value of Data. This assumes your 
MIDI controller either has a data slider, or a programmable control that you set to send Data 
messages (MIDI 06). If you don’t have a data slider or a programmable control, you can set the 
value of Input b to AbsPwl, and use your Pitch Wheel to control Input b. If you do this, you’ll