If you go into part edit for these parts and then control assign, set the display filter to All and you'll notice that Volume is a parameter that is assigned to one of the controllers (Assignable Knob 1). In these instances controllers take precedence over the volume slider.

Hello Gary - this one had me fooled for a while too, but it's as Phil says, of course. It's an extra hurdle for sound-makers to get over in that you must first un-pick the sound you want to use - which means you may not want to use it! Catch 22 ...

Why is it programmed like that? Is it intentional?

Yes Hale it would certainly be intentional. The use of controllers opens up a much more expressive way of playing the instrument (which of course you can edit out if you want to). The audition button is a good place to start as it will give an indication of the way in which the programmers intended the performance to be used. Plus you can also see the knobs, switches at work so you can see the affect they have.

Hale wrote:

Why is it programmed like that? Is it intentional?

Yes, it is intentional. And is only a head scratcher when you first come upon it in another person's programming. It's a decision made by the programmer when they are deciding what would be the best way to control a specific portion of a multi Part program _ one with multiple components that require individual attention.. That multi-dimensional thing.

It is in the assignment of controllers, and making them work across multiple Parts that you begin to run into these seeming anomalies where the main volume (fader) is not in charge of the output level. This can occur, specifically, when you (as programmer/performer) would like to assign direct control of this parameter to an assignable knob.

In standard MIDI protocol where you are addressing multiple Parts you typically have the option of
1) using cc007 Main (channel) Volume - which affects everything on the MIDI channel, forcing all components to the same exact value,
2) you could use cc011 Expression - which affects everything on the MIDI channel but keeps all components in a proportional volume relationship,
_These two Control Change items are your typical control options, which can be set on a per Part basis. Each Part has a Receive Switch which can opt in or out on the Control Change message.

or
3) as is the case here - you can assign the Part Volume parameter to direct control of, say, an Assign Knob. When you assign direct control over the "Part Volume" destination to an Assign Knob, the position of that Assign Knob is responsible for the output volume of that Part. It will supercede the cc setting. Thus adding flexibility... You can opt to have the sound present or hidden at the time the program is initially recalled. You can also design, quite intracately, the application of the parameter change. It does not have to be linear application.

You can find this direct assignment inside the PART EDIT parameters... Control Assign screen.

The removal of the CONTROL ASSIGN (Source/Destination) Control Set that links an AssignKnob to the Part Volume, will return control to the Fader. When you run across this, it typically designed so that either by moving the AssignKnob itself or through that AssignKnob's link to the Super Knob movement, you are dynamically 'performing' a volume morphing operation, or something similar.

When programming keyboard control over multiple Parts, you will quickly want to break free of the "all or nothing" type control offered by standard MIDI messages cc007 and cc011; the Control Assign matrix in the Montage, while initially a head scratcher, is at the core of its innovative synthesis method. Instead of just moving *all* Part's volume up or down together, you can fashion individual direct volume change for each Part you have under KBD CTRL.

And on an even deeper level, when programming control over multiple Elements/Operators within a Part, you want to have a precision tool, like this direct parameter assignment (Element Level or Operator Level), versus the broad channel-wide Control Change type of control. A scalpel versus an axe, both cut...

You will discover that you can now begin to setup non-linear changes in things like volume which can open new avenues of sonic control.
Suggestion: Learning to navigate the Control Assign screens is an important Montage skill. And learning to use the "Display Filter" and the Motion Control "Overview" to analyze assignments will serve you well when studying factory setups (before embarking on your own creations).

The Control Assign matrix really acts as a way to assign real time knob control to a couple of hundred parameter destinations... among them Part Volume, Element Level, Operator Level.