a general damp of everything left and right
A similar kit is a 1/3rd octave (aka 31 band) equalizer. PEQ's gave you centers that you can move around and maybe select the shape among a couple settings, and two or three cheap PEQ's were sometimes built into the fixed center EQ units, or from the same maker. The 31's analog function has also been emulated with digital / software tools. DJ forums are another place to look for the SW tools, but DJ stuff is often not free opensource. https://en.wikipedia.org/wiki/Rhythmbox https://ubuntustudio.org/ https://lsp-plug.in/ https://github.com/TheBigW/ParametricEQ http://cefiso.blogspot.com/2016/09/basic-guide-to-understanding-audio.html https://img.canuckaudiomart.com/uploads/large/1283387-a91d094c-sae-2800-soli... https://static.kvraudio.com/i/b/para_equalizer_x32_ms.png