[LAU] Implementing a crossover with ladspa plugins?

[Fons Adriaensen]

On Tue, Jul 03, 2012 at 12:41:58PM -0400, S. Massy wrote:
> Hello, all,
> Here's a question for the fine DSP and accoustic experts on this list. I
> need to apply different processing (mostly reverb and compression) to
> different bandwidths of the frequency spectrum on a given track. How
> would I go about using filters to implement crossovers as flat as
> possible? Most plugins do not actually seem to tell what their rolloff
> curve is. 

* The outputs of first order xover filters will add to exactly the
  input signal. But you only have 6 dB/oct and hat may or may not
  be enough, depending on the application.

* If you want steeper (higher order) filters one solution is to
  us the Linkwitz-Riley type. Outputs add to a perfectly flat
  frequency response, but the phase response of the recombined
  signal is not linear. It won't matter in most cases.

For ready-to-use L-R filters, get zita-lrx1. It provides up to
four bands using 4th order filters (i.e. 24 dB/oct).

Ciao,


-- 
FA

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