Gaussian Filter Prototype Element Values (to 6 dB & to 12 dB) - RF Cafe
Filter slope - Apple Support
Bode Plots
Analog filters
How do speaker manufacturers calculate the -6dB frequency cutoff? | Audio Science Review (ASR) Forum
What makes 6dB filters so special – Just Blogging
Further With Filters
Resonant filters
Project 170
Should the slope of your filter be 6, 12, 18 or 24 dB per octave?
Band-pass filter 6dB per octave
First Order Passive Crossovers, 6 dB per Octave
Spectrum Analyzer Basics: Bandwidth - Siglent
How to design Shelf and Butterworth HP or LP 6db/oct, 12db/oct filter? - Q&A - SigmaDSP Processors & SigmaStudio Dev. Tool - EngineerZone
Numbers in Audio
Why do the orders of hi/low pass filters go in 6 dB increments? - Sound Design Stack Exchange
Filter Circuits with Capacitors
Linkwitz–Riley filter - Wikipedia
1st Order / 6 db Butterworth Crossover Table
operational amplifier - Is the cut-off frequency of a 4th-order filter at -12 dB or -6 dB? - Electrical Engineering Stack Exchange
High-Pass Filter - Audacity Manual
