A low-pass filter calculator is a calculator which calculates the cut-off values for the high-frequency sounds which need to be attenuated, or cutoff before broadcast. This works by allowing low-frequency sound to go to the woofers and tweeters in the microphone circuit before being broadcast. These calculators will give the amount of resistance necessary, and some will give the specific capacitor needed for the intended function. They are used when building microphones and other sound systems. There are many types of low pass filter calculators and some are available for free download on Google. There are low pass filter calculators available for guitar pedals, which are designed to prevent the high-pitched noise emitted by some electric guitars when they are first played. There are other filters which are meant to be applied to radio frequencies. A low pass filter results in a smoother form of the frequency by removing short-term fluctuations. These are commonly used to reduce the “hissing” noise that used to be common in radio transmissions. Another use of low pass filter calculators is in the financial sector, where the use of a low pass filter smoothes out the flow in sets of data. Thus, sudden sharp peaks in the data are smoothed out, and the general trend of the data set is easier to calculate. This low pass filter is called a “moving average” and is used when projecting financial trends. An example of an everyday use of a low pass filter is when a neighbor turns their radio on in an apartment complex. To the people in another room, the sound is muted and the higher frequencies emitted by the radio are barely heard, but the lower notes of the music being played are still noticeable. A practical application of this principle is that the sound of a television or radio will tend to cover up the sounds of conversation. This is a reason why people seeking audible privacy often turn a radio or television on before beginning a conversation. Of course, this method, being a method devised by improvisation, is not perfect, and the conversation is not covered completely. This does bring up another fact; that being that there is no such thing as a perfect low pass filter. The reason for this is that in order to eliminate all sound above a certain frequency, one must assume the frequency wills last forever, which is not possible for sound, or for any other phenomenon being filtered.