Another way to combine signals together is by using element-wise multiplication. This can be used to create amplitude fades and also amplitude modulation for the tremolo effect.

In Matlab, it necessary to use a period before the multiplication operator to specify the point-wise (or element-wise) multiplication. This is written: $y = x .* w$. For the signals, $x = \{ {x}_{1},{x}_{2},\hdots,{x}_{n} \}$ and $w = \{ {w}_{1},{w}_{2},\hdots,{w}_{n} \}$, the element-wise multiplication of the signals is:

$y = \{ {x}_{1} * {w}_{1},{x}_{2} * {w}_{2}, \hdots,{x}_{n} * {w}_{n} \}$.

Next, we can use signal multiplication to create amplitude fades.