are_wave">https://en.wikipedia.org/wiki/Square_wave</a>):</p>
<!-- faust-run -->
<div class="faust-run"><img src="exfaust33/exfaust33.svg" class="mx-auto d-block">
<faust-editor><!--

import("stdfaust.lib");

// Approximation of a square wave using additive synthesis

squarewave(f) = 4/ma.PI*sum(k, 4, os.osc((2*k+1)*f)/(2*k+1));

process = squarewave(55);

--></faust-editor>
<br>
</div>
<!-- /faust-run -->
<p>As an exercise, change the number of harmonics to see the approximation improve (but do not exceed 