com.softsynth.jsyn
Class Filter_1o1p

java.lang.Object
  java.util.Observable
      com.softsynth.jsyn.SynthObject
          com.softsynth.jsyn.SynthSound
              com.softsynth.jsyn.SynthUnit
                  com.softsynth.jsyn.SynthFilter
                      com.softsynth.jsyn.Filter_1o1p

public class Filter_1o1p
extends SynthFilter

Filter_1o1p unit. First Order, One Pole filter using the following formula:

y(n) = A0*x(n) - B1*y(n-1)

where y(n) is Output, x(n) is Input and y(n-1) is a delayed copy of the output.

This filter is a recursive IIR or Infinite Impulse Response filter. It can be unstable depending on the values of the coefficients. This can be useful as a low-pass filter, or a "leaky integrator".

A thorough description of the digital filter theory needed to fully describe this filter is beyond the scope of this document. Calculating coefficients is non-intuitive; the interested user is referred to one of the standard texts on filter theory (e.g., Moore, "Elements of Computer Music", section 2.4).

Version:

JSyn Version 006

Author:

(C) 1997 Phil Burk, SoftSynth.com, All Rights Reserved

See Also:

Synth, SynthUnit, Filter_1o1z, Filter_1o1p1z, Filter_2o2p, Filter_2o2p2z, Filter_StateVariable

Field Summary

SynthInput	A0 Filter coefficient.
SynthInput	B1 Filter coefficient.

Fields inherited from class com.softsynth.jsyn.SynthFilter

input, output

Constructor Summary

Filter_1o1p()

Filter_1o1p(SynthContext synthContext)
Create a SynthUnit that runs at Synth.RATE_AUDIO.

Filter_1o1p(SynthContext synthContext, int calculationRate)

Method Summary

Methods inherited from class com.softsynth.jsyn.SynthSound

addPort, addPort, findNamedPort, getName, getNumPorts, getPortAt, getPriority, setPriority, setStage, setStage, start, start, stop, stop

Methods inherited from class com.softsynth.jsyn.SynthObject

delete, deleteAll, enableDeletionByGarbageCollector, enableTracking, getPeer, getSynthContext, isTrackingEnabled, toString, track

Methods inherited from class java.util.Observable

addObserver, countObservers, deleteObserver, deleteObservers, hasChanged, notifyObservers, notifyObservers

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

A0

public SynthInput A0

Filter coefficient. SIGNAL_TYPE_RAW_SIGNED, default = 0.6.

B1

public SynthInput B1

Filter coefficient. SIGNAL_TYPE_RAW_SIGNED, default = 0.3.

Constructor Detail

Filter_1o1p

public Filter_1o1p(SynthContext synthContext,
                   int calculationRate)
            throws SynthException

Throws:

SynthException

Filter_1o1p

public Filter_1o1p(SynthContext synthContext)
            throws SynthException

Create a SynthUnit that runs at Synth.RATE_AUDIO.

Throws:

SynthException - If resource allocation fails.

Filter_1o1p

public Filter_1o1p()
            throws SynthException

Throws:

SynthException