If the temperature is below setpoint, the output will be on longer; if the temperature is too high, the output will be off longer. The third controller type provides proportional with integral and derivative control, or PID.
Amplifier figures of merit. In electronics, the figures of merit of an amplifier are numerical measures that characterize its properties and performance. Figures of merit can be given as a list of specifications that include properties such as gain, bandwidth, noise and linearity, among others listed in this article. Figures of merit are important for determining the suitability of a particular amplifier for an intended use.
The relationship between sound and noise levels is generally described in terms of a signal-to-noise ratio. With a masking noise level between 35 and 100 dB, the threshold for 100% intelligibility is usually a signal-to-noise ratio of 12 dB. The speech signal ranges from about 200-8000 Hz, while human hearing ranges from about 20-20,000 Hz, so the effects of masking depend on the frequency range of the masking noise.