Review - Broughton Audio: Josh Wah, Low+High Pass Filter, and Apex Compressor - Bass Musician Magazine, The Face of Bass
DMT Dual Mode High & Low Pass Tone Control
Recording Dojo: A High Five for the Low-Pass Filter - Premier Guitar
Filters - Low Pass and High Pass | Amplified Parts
High Pass Frequency On Bass Guitar: Pros And Cons – FuelRocks
NPD - Broughton Low + High Pass Filter. Does a great job of cleaning up muddy low end and hissy high end frequencies I don't want. Just the creamy middle! : r/BassGuitar
How to EQ Bass Guitar: Simple Steps for a Better Low End - Produce Like A Pro