GuDa Audio has announced the release of FiltR, a freeware multi-mode filter effect in VST and AU plugin formats for compatible digital audio workstation applications on PC and Mac.
FiltR features the same set of filters as the ones used in GuDa Audio’s previously released SynthR ($59) virtual analog synthesizer. There are seven different filter modes to choose from, including transistor ladder filters, diode ladder filters, and SVF filters. The plugin doesn’t include any presets.
See also: Download FREE VHL-3C Pultec Filter VST/AU Plugin By Black Rooster AudioThe filter algorithms used in FiltR sound quite good. The plugin doesn’t attempt to be a super accurate emulation of analog hardware, but it does capture the general sonic character of the simulated filter types while being relatively easy on the CPU. The processed signal is 2X oversampled at all times to help prevent digital audio artifacts from occurring. With seven different filter modes on board, there’s enough variety to conform to different mixing and sound design scenarios.
Functionality-wise, FiltR is a rather straightforward mixing tool. It doesn’t come with any advanced features like modulation or side-chain support. Instead, you’re getting a simple user interface with just three control parameters for adjusting the cutoff frequency, resonance, and filter drive. The drive parameter is only compatible with the transistor ladder, diode ladder, and K2 pole filter models.
The user interface can be zoomed in for increased compatibility with differently sized computer screens. The color scheme can also be adjusted, offering different combinations of background and highlight colors.

FiltR can be downloaded completely free of charge from the product page linked below. The user doesn’t need to register nor activate their copy of the plugin. GuDa Audio is also offering a range of other plugins such as the KickR ($24) kick drum synthesizer and the Drumr ($39) virtual drum machine.
FiltR is available for free download via GuDa Audio (8.4 MB download size, ZIP archive, 32-bit & 64-bit VST/AU plugin formats for Windows & MacOS).