Learn how to construct a few common filters, and design your own delay effect from scratch.
Exercise 5: Audio Filters and Delays
We’re learning how to...
- create in Max a resonant lowpass filter,
- design a basic delay effect with feedback and smoothly changing delay time,
- create a stereo delay effect by providing a separate delay line for each channel, and
- feed the filtered signal into the two delays, and make a few presets that capture parameters you like.
How to Do This Exercise
Working on the assignment is a three-stage process: studying the tutorial patches, watching some short instructional videos, and making a patch that sends a filtered sound into a stereo delay effect.
- Download Exercise 5 Max Tips. This folder of Max patches shows you how to use two common filter objects and implement a delay effect with feedback.
- Watch the following videos, in the order listed. You could go through the tutorial patches carefully instead, but the videos will probably get you closer to understanding a solution for this assignment. Use whatever method works for you: tutorial patches or videos.
- Make a patch that creates a delay effect with feedback. Use
a sound file player to test it. Then create a resonant
low-pass filter using biquad~, controlled by
filtergraph~, and patch the filter between the sound
file player and the delay effect. Finally, duplicate your
delay effect, so as to create a stereo delay effect, with
different delay times for the two channels. Save some delay
parameters in presets.
To summarize, your patch should have
- a sound file player, which feeds
- a resonant low-pass filter, which feeds
- two delay effects in parallel, which connect to
- the two channels of a live.gain~ and ezdac~.
It would also be nice to have the ability to adjust the wet/dry mix for the delays. You could add another live.gain~ for the signal coming directly out of the filter — this would be the dry signal — and connect both faders to the ezdac~.
Later we will learn how to use a crossfader to implement a more convenient wet/dry mix control. The last video above demonstrates another solution.
Be sure you understand what each of these Max objects does:
- biquad~, filtergraph~
- tapin~, tapout~
- Be sure you satisfied the criteria listed above.
- Submit your Max patch in Canvas.
This exercise is graded pass/fail. You must submit the exercise by Thursday midnight to be eligible for a pass.
Your patch must
- operate correctly and
- implement the functionality described in the “How To Do This Exercise” section above.