EffectModule is a logical group of Players
and/or MIDI channels to which a common sequence of effects can be applied.
The GlobalManager is used to retrieve EffectModules.
This allows optimizations in the audio processing. For example, the implementation
might mix all of the inputs together before applying the effects. The term
effect is used here to cover both effects extending EffectControl and
effect-like Controls extending Control like VolumeControl of
MMAPI.
The set of effects provided by an EffectModule in
S60 is a set which all the Players connected to the EffectModule support.
A given EffectModule, one that has no Players
attached to it, does not provide any Controls. At least
one Player can always be added to an EffectModule,
but adding a MIDI channel or a second Player will not
necessarily work. For instance, if the second Player is
of a type that would make aControl already retrieved
from the EffectModule become obsolete, adding the second Player is
not allowed and a MediaException is thrown. In all essential
parts in the guidelines above, the Player can instead
be a MIDI channel, when the device supports access to individual MIDI channels.