The linuxDSP graphical EQ is now available as a linux VST plugin. You can download it from:
http://www.linuxdsp.co.uk/download/vst/download_graph_eq_vst/index.html
Or if you haven’t already tried the LV2 version and you want to give it a try with ardour you can download it from:
http://www.linuxdsp.co.uk/download/lv2/download_graph_eq/index.html