JIMMY!
The metronome was invented by Dietrich Nikolaus Winkel in Amsterdam in 1812. Johann Mälzel copied several of Winkel's construction ideas and received the patent for the portable metronome in 1816. Ludwig van Beethoven was the first well-known composer to indicate specific metronome markings in his music, in 1817, but many performances of his music still vary widely from his tempo indications, particularly in slow movements.
Musicians use metronomes when they practice in order to maintain an established tempo; by adjusting the metronome, facility is achieved at varying tempi. Even in pieces that do not require strict time (see rubato), a metronome is used to give an indication of the general tempo intended by the composer. Many pieces provide a tempo indication at the top of the manuscript.
One common type of metronome is the wind-up metronome, which uses an adjustable weight on the end of a rod to control the tempo: slide the weight up the rod to decrease tempo, or down the rod to increase tempo. The pendulum rod swings back and forth in tempo; mechanics inside the metronome produce a clicking sound on each swing of the rod.
Most modern metronomes are electronic, with a quartz crystal to maintain accuracy, comparable to those used in wristwatches. The simplest electronic metronomes have a dial or buttons to control the tempo; some can also produce a tuning note (usually A440 hertz). They range from simple credit-card sized devices to the complicated "Dr. Beat", manufactured by Boss, which can play polyrhythms and can "count aloud", using a sampled voice.
Sophisticated metronomes can produce two or more distinct sounds. A regular "tick" sound indicates the beat within each measure, and another, distinct sound (often of a different timbre, higher pitch and/or greater volume) indicates the beginning of each measure. A tempo control adjusts the amount of time separating each beat (typically measured in beats per minute), while another, discrete, control adjusts the meter of the rhythm and thus the number of beats in each measure. This number is an integer often ranging from one to six, though some metronomes go up to nine or higher. Some devices also have options for irregular time signatures such as 5/4 or 7/8, in which other distinct sounds indicate the beginning of each subgroup of beats within a measure.
For example, if the user selects four beats per measure (for example a time signature of 4/4), then the metronome might sound like so:
Ching!, tick, tick, tick,
Ching!, tick, tick, tick, …
while an irregular meter of 7/8 might produce this pattern:
Ching!, tick, tock, tick, tock, tick, tick,
Ching!, tick, tock, tick, tock, tick, tick, ...
Another pattern for 7/8 is
Ching!, tick, tick, tock, tick, tock, tick,
Ching!, tick, tick, tock, tick, tock, tick,...
Many electronic musical keyboards have built-in metronome functions.
The word metronome first appeared in English c.1815, and was formed from the Greek words:
metron = measure, and nomos = regulating
JIMMMY!!!!!!!!! **** ! (sorry)