of Microprocessors

20
Low-CostSYllthesis
Techniques
While research and high-end applications of computer music synthesis enjoy
the most glamour, more utilitarian applications are also important and can be
interesting as well. A professional synthesizer, such as described in the
previous chapter, would probably be considered "successful" if more than
5,000 were sold during its lifetime. At, say, $3,000 each, the gross income
would be $15 million. A successful research system may have sales of only a
few hundred units, but, even at its much higher price, there would be less
total income. A popular musical toy, however, may very well sell in the
millions of units. Even though the price might be only $30 or so, the income
generated could be much greater than the two previous examples.
Designing sound-generation circuits for a high-volume toy or game is
actually much more challenging than designing a professional or research
synthesizer. In the latter case, the designer is interested mostly in a "clean"
design that performs flawlessly. Manufacturing costs, while kept in mind
during the design, are usually not of prime importance. In a high-volume
product design, elimination of a single resistor with an installed cost of one
cent can save $20,000 over a 2 million unit production run. That kind of
savings is sufficient to justify having an engineer spend an entire month or
more full-time studying whether that resistor can be removed. An excellent
design in this context is one that is cheap to produce and performs adequately
and safely.
Although fussing over individual components is often productive, the
initial selection of synthesis technique is by far the most important decision
to be made in a high-volume product design. In this chapter, some low-cost
techniques will be examined and then their application to several low-cost
products will be described.
Applications of Low-Cost Synthesis
Many types of products today use electronic sound generation in their
operation. Mechanical sound generators, such as bells, buzzers, Sirens,
757