Christian Budde has released Dual Linkwitz-Riley Filters, a plug-in that offers a pair of stereo Linkwitz-Riley Filters. It can be used as a lowpass, highpass or bandpass filter and has been optimized to be used in a virtual digital crossover network.
- Variable order cascaded butterworth filters (AKA Linkwitz-Riley filters).
- Automatic phase compensation (for 2-way systems).
- Low CPU usage.
- Open source (MPL / LGPL).
- Preset exchange across the instances.
Dual Linkwitz-Riley Filters is free and is available for Windows as a VST effect plug-in.