Polycom SoundStructure C16 Design Manual page 405

hpf_order Order of High-Pass Filter
Argument Argument value
Channel Type Virtual Channel
Value Type Integer
Read/Write Mode Read/Write
Phys Chans Conferencing Mic/Line Input, Conferencing Line Output,
Sound Reinforcement Mic/Line Input, Sound Reinforcement
Line Output, Analog Telephony Input, Analog Telephony
Output, Submix, ConferenceLink Aux Input, ConferenceLink
Aux Output
Virt Chans Mono, Stereo
System Limits Minimum: 1, Maximum: 8
Default 2
User Limits No
Supported
Description
This parameter sets the order of the high-pass filter. Linkwitz-Riley filters only
support even orders. If an odd order is specified for a Linkwitz-Riley filter, it
will be internally rounded up to an even number.
hpf_type Type Of High-Pass Filter
Argument Argument value
Channel Type Virtual Channel
Value Type List
Read/Write Mode Read/Write
Phys Chans Conferencing Mic/Line Input, Conferencing Line Output,
Sound Reinforcement Mic/Line Input, Sound Reinforcement
Line Output, Analog Telephony Input, Analog Telephony
Output, Submix, ConferenceLink Aux Input, ConferenceLink
Aux Output
Virt Chans Mono, Stereo
Values butterworth : Butterworth filter (default)
linkwitz_riley : Linkwitz-Riley filter
Description
This parameter sets the type of analog filter prototype used for the high-pass
filter.
Command Protocol Reference Guide
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