Most algorithms have multiple modulators and carriers. In one algorithm a given operator may be a carrier, while in the next it might function as a modulator—the only difference being how it is connected. In algorithm number 5 for example, there are two vertical stacks of two operators, and the outputs of the carriers in these stacks are connected in parallel (horizontally). Algorithm 5 has an equal number of modulators and carriers—two modulators and two carriers.

On the other hand, all operators in algorithm 8 function as carriers. Note that no modulation can occur in this algorithm (except for the feedback loop on operator 4—we’ll discuss that later). But algorithm 8 is ideal for creating rich organ voices— think of each operator as different organ “stops,” which can be mixed together as desired.

The algorithm alone, however, does not determine the actual sound of the voice. The vital characteristics of the voice you create depend mostly on the frequencies and levels you program into each operator. The 8 algorithms provided in the DX27 were specially selected because they offer the broadest range of voice programming possibilities.

The results of using different frequency ratios, as well as different algorithms, are shown graphically in the accompanying illustration. In the left column, you see the waveforms created by 1:1, 2:1 and 3:1 ratios between one modulator and one carrier. In the right column, you see the waveforms which result from the same three ratios, but when the two operators used are both carriers (connected horizontally, this is known as additive synthesis).

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