Can anyone recommend any filters with an envelope follower?

[ArrenMog]

I was wondering whether anyone could recommend any filters that they are aware of that use an envelope follower to control the cut off point?

What I mean by envelope follower is that the cutoff point of the filter is controlled by the dynamics of the input signal (when the sound gets louder the filter opens more).

I saw Icicle using Sugar Bytes Wow filter but I don't currently want to spend the $99 to buy it and was wondering if anyone knew of any cheap or free alternatives?

Thanks!

[webstarr]

Wow Filter, it's a brilliant tool

[ArrenMog]

Wow Filter, it's a brilliant tool

Haha yeah I understand it's good, I was wondering if there was a cheap or free alternative?

[penguinoid]

half the cost of Wow, so definitely cheaper:
http://www.audiodamage.com/effects/prod ... ?pid=AD029

if you want free, the only one I can think of is MDA's Rezfilter:
http://www.kvraudio.com/product/rezfilter_by_mda
if you can handle the terrible gui (or lack thereof)