Is the use of IIR filters for audio processing is a good idea?.

Hi all,

 what are the effects of using IIR filter on audio signal?.
	

Hi,

As long as you design the IIR filter to have linear phase in the passband,
everything should be fine.

Regards,

Bobby
	----- Original Message ----- 
From: "kssubrahmanya" <kssubrahmanya@kssu...>
To: <audiodsp@audi...>
Sent: Friday, May 06, 2005 3:20 PM
Subject: [audiodsp] Is the use of IIR filters for audio processing is a good
idea?.
	> Hi all,
>
>  what are the effects of using IIR filter on audio signal?.
>
>
>
>
>
>
> 
>
>
>
>
>
>
	

Hi Jon,
There are a few techniques available which can be used to convert large FIR
filters to much smaller IIR equivalent ones (keeping the phase linear in the
passband if the prototype was a linear phase FIR).
You can read the following paper which describes one such algorithm:
Beliczynski, B., I. Kale and G. D. Cain, "A balanced model reduction
algorithm for transforming FIR to IIR approximants", IEEE Trans. Sig.
Proc.,
vol. 40, no. 3 , pp. 532-542, March 1992.

Me and my colleagues have written a digital filter design package which uses
a different algorithm to do the same thing.
(http://www.dspcreations.com/Products/sketchafiltsales_writeup.htm)
With this tool you can design your linear-phase (in passband) IIR and also
impose wordlength effects on the coefficients.. furthermore, you can play
audio through it and listen to the IIR filter working!
	Hope this helps.
Regards,
Bobby
	----- Original Message ----- 
From: "larkjon" <jon.lark@jon....>
To: "Bobby Mughal" <bmughal@bmug...>
Sent: Monday, May 09, 2005 3:31 PM
Subject: Re: Is the use of IIR filters for audio processing is a good idea?.
	> Hi,
>
> Regarding Bobby's reply; anybody know of an algorithm for designing a
> linear phase IIR filter?  The only way I know of is to transform an
> analog filter that has approximately linear phase, such as a Bessel
> or equi-ripple phase filter, via the impulse invariant z transform.
> Is there something analgous to the Parks-McClellan FIR algorithm?
>
> Regards,
> Jon
>
>
> --- In audiodsp@audi..., "Bobby Mughal" <bmughal@d...>
wrote:
> > Hi,
> >
> > As long as you design the IIR filter to have linear phase in the
> passband,
> > everything should be fine.
> >
> > Regards,
> >
> > Bobby
> >
> >
> >
> > ----- Original Message ----- 
> > From: "kssubrahmanya" <kssubrahmanya@y...>
> > To: <audiodsp@audi...>
> > Sent: Friday, May 06, 2005 3:20 PM
> > Subject: [audiodsp] Is the use of IIR filters for audio processing
> is a good
> > idea?.
> >
> >
> > > Hi all,
> > >
> > >  what are the effects of using IIR filter on audio signal?.
> > >
> > >
> > >
> > >
> > >
> > >
> > > 
> > >
> > >
> > >
> > >
> > >
> > >
>
>