The tone control extended block can generate filters and their coefficients and then of filtering audio signals passed to the audio block based on the calculated coefficients. The tone control extended object can have a variable number of channels and have one set of filter coefficients per element for all channels. It has an adjustable number of elements or cascaded filters
This audio object applies filter on all the channel. When filter parameters are changed during run time, the filter coefficients are gradually changed to target values using ramping. Linear interpolation is used for filter ramping. Filter coefficients are ramped after every pre-configured number of samples for ramping. This ramping is applied until filter coefficient reach target value.
In the SFD, users can select the number of channels and the number of filters that they prefer. The number of input channels is always equal to the number of output channels.
For each filter in the tone control, this object exposes these five tuning parameters to the GTT:
- Frequency (cut-off)
- Gain (in dB)
- Q-value
- Type of filter:
- Allpass order 1
- Allpass order 2
- Highpass order 1
- Highpass order 2
- Lowpass order 1
- Lowpass order 2
- Highshelv order 1
- Highshelv order 2
- Lowshelv order 1
- Lowshelv order 2
- Peaking (EQ)
- Bandpass
- Bandstop
- Amplifier
- Reson
- RampTime
There are no control output and three control inputs per filter element. Using control inputs user can change cut off frequency, Gain and Quality factor.