Japanese
★ SOUND Manual ★ Sound development manual
▲ Back ｜ Forward ▼
Sound Development Manual/1. Overview

■About FM (Frequency Modulation)

FM is famous for products such as YAMAHA's DX7, but in this system's FM, the basic waveform is not limited to sine waves. Any waveform data in AIFF format can be used as a carrier or modulator. You can also freely configure the algorithm for combining them. It is also possible to change the modulation depth depending on velocity. The biggest problem with FM is that the carrier and modulator each use one slot, which reduces the number of polyphony. However, if you have one basic waveform (such as a sine wave) as waveform data, you can create a variety of tones through FM modulation, so it is very useful when you do not want to increase the tone bank data due to limitations such as RAM. It seems that.

The sound memory on the target board is 1024KByte, but on the actual device it is 512KByte. The portion minus sequence data, DSP programs, work RAM, etc. will be allocated to the tone. Even if you reduce the sampling rate, it is practically impossible to store dozens of PCM waveforms with a large amount of data in memory at the same time.

▲ Back ｜ Forward ▼
★ SOUND Manual ★ Sound development manual
Copyright SEGA ENTERPRISES, LTD., 1997