Linear Phase Eq versus Minimum Phase Eq is an important distinction and one should strive to have a basic understanding of the differences between the two. Analogue equalisers (minimum phase) tend to colour the sound in a way that’s more complicated than simple frequency boosts and cuts because they introduce phase shifts whereas linear phase equalisers have no phase shifts when boosting or cutting between low and high frequencies. In most mix scenarios we tend to opt for linear phase equalisation for surgical corrective tasks and minimum phase equalisation for colour.
However, that has changed over the years and we quite happily interchange one topology for another when performing either corrective or creative processes.
A number of software equalisers offer both linear phase and minimum phase and some even introduce their own variations: FabFilter also offer ‘natural phase’ as an option. It helps to read the manuals provided with most eq plugins as there are variations for all manner of phase goodies. However, minimum phase designs can also be used for precision equaliser tasks. It is not as clear cut as it used to be when it was either or when it came to surgical equaliser tasks.
To fully understand how Linear Phase Eq versus Minimum Phase Eq differ it is best to watch the video. I have made sure to simplify it and to show you every eventuality using both topologies. Watching the responses of both linear and minimum phase equalisers on a graph is a great visual way to understand what happens to the frequency response of each topology.
The plugin used in this video: FabFilter Pro Q2
Topics covered in this video are:
- The differences between Linear and Minimum Phase Topologies
- Zero Latency and Minimum Phase
- Understanding Phase and Shifting/Response
- Measuring Frequency Response
- Measuring Harmonic Distortion
- Cut versus Boost
- Slopes and Q (bandwidth)
- Using Analysers and Measuring
- Peaking and Shelves
If you enjoyed this tutorial maybe these will also help:
What is an equaliser and how does it work
EQ Uncovered – (second edition)
Eq Filters and Slopes/Responses
Active, Passive, Graphic, Parametric, Fixed and Peaking Eqs