Re: [linux-audio-dev] IIR dc-buildup

[Niels A. Moseley]

Hi!

Sorry for butting in...

>I've got lot of stability problems with high order IIR lowpass filters.
>Those tend accumulate significant DC offsets over time. OK for short samples
>but not for realtime streaming, IMHO.
>
>Of course I could add DC notch after LP but that would mess the phase
>response and getting the response steep enough would be hard.

Does this DC buildup occur in direct-form IIR filters or do you use a
serial biquad structure?

Cheers, Niels.