Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See page_maxonapi_getting_started_foundations_cinema_parameters.
Parameter: Sound File
MGSOUNDEFFECTOR_FILE
Parameter: Start Offset
MGSOUNDEFFECTOR_START
Parameter: Apply Mode
MGSOUNDEFFECTOR_MGMODE
Parameter: Falloff
MGSOUNDEFFECTOR_FALLOFF
Parameter: Sample Mode
MGSOUNDEFFECTOR_MODE
Parameter: Clamp Output
MGSOUNDEFFECTOR_CLAMP
Parameter: Lower Cutoff
MGSOUNDEFFECTOR_LOWERLIMIT
Parameter: Compression
MGSOUNDEFFECTOR_MULTIPLIER
Parameter: Frequency Graph
MGSOUNDEFFECTOR_GRAPH
Parameter: Filter Shape
MGSOUNDEFFECTOR_FILTERSHAPE
Parameter: Frequency Color
MGSOUNDEFFECTOR_COLORGRADIENT
Parameter: Frequency
MGSOUNDEFFECTOR_FREQ
Parameter: Bandwidth
MGSOUNDEFFECTOR_BANDWIDTH
Parameter: Left Channel
MGSOUNDEFFECTOR_LCHANNEL
Parameter: Right Channel
MGSOUNDEFFECTOR_RCHANNEL
Parameter: Use Filter
MGSOUNDEFFECTOR_FILTER
Parameter: Play
MGSOUNDEFFECTOR_PLAY
Parameter: Scrub Sound
MGSOUNDEFFECTOR_SCRUB