Pulse Wave

The pulse wave is slightly more complicated, because it is not one waveform, it is many different ones. A pulse wave is a waveform that during one period jumps once between full positive amplitude and full negative and then back. The thing that can be varied is where within the period you jump from maximum to minimum amplitude. Let’s look at three examples:

Pulse Wave (пульсирующая волна)

Пульсирующая волна немного сложнее, потому что это не одна форма, а много разных. Пульсирующая волна — это сигнал, который в течение одного периода скачет один раз между полной амплитудой положительной и полной отрицательной, а затем обратно. Что может измениться в период скачка с максимальной до минимальной амплитуды. Рассмотрим три примера:

In the first, the jump happens 5% in from the beginning of the period. This is referred to as a pulse wave with a 5% pulse width(sometimes called duty cycle). The second wave has a pulse width of 10%. The third wave has a pulse width of 50%.

This third wave is a special case of the pulse wave, called a square wave, and this has one peculiarity, it only contains odd number harmonics, which gives it a “hollow” quality.

On many synthesizers (including the Nord Lead) the pulse width can be adjusted, to set the timbre of the pulse wave. The more narrow the pulse width, the more “thin” the sound will be.

You can also have the pulse width vary continuously, for example from an LFO or envelope. This is referred to as pulse width modulation. Modulating pulse widths from an LFO creates a rich, chorus-like effect often used in “string” sounds.

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