I’ve explained in earlier posts how to simulate a simple overdrive circuit. I’ve also explained how I implemented this in QtVST (and yes, I should have added labels on those images!), which was more or less the predecessor of Audio TK.
The main problem with simulating non linear circuits is that it costs a lot. Let’s see if I can improve the timings a little bit.
A long time ago, I started implementing audio filters with a Qt GUI. I also started other pet projects in the same area, but I didn’t have a proper audio support library in C++ for that. Also Qt plugins are no longer an option (for me), I still hope to implement new filters in the future.
How to explain the different kind of audio effects and how to understand what their use is? Although I learnt a lot by practice, there is sometimes the need for some theory and for experiments. I tried to find a book that matches these two points: good theory and proper practice. I’ve chosen this book, with tracks on a CD for experimentation. Was it really what I was looking for?
I think I’ve said it already, I have a rock band. Currently, we are recording our first album, and while we used Traktion in the past, I’m considering moving to Sonar (it is continuously updated and has a great reputation, also I’ve played a few time in the past with its ancestor Cakewalk).
So let’s talk about the book’s comprehensive guide.
I’m pleased to announce the 1.0 version of QtSimpleEQ, a plugin with one low-pass, two peak and one high pass second-order filters. Nothing fancy in the algorithms, it’s mainly another show case for Qt VST plugins.
A few months ago, I’ve posted a note on an overdrive. The main issue of this kind of non-linear filter is aliasing, a process that adds digital acoustic content. The best way to solve the issue is to oversample the input before processing the signal.
There are some effects that are simpler than other. Digital ones are generally easier than analog ones, and purely digital filter are also easier than digitally-transformed analog ones. Linear filters such as passband, cutband, … are easy to digitally design, chorus can be achieved through some spectral computations, delay and reverbation are computationnally expensive but easy to code.