What do tuning pegs do?  Tuning Pegs (Tuning Machine Heads) is a part of the guitar, but few people pay special attention to it. It is one of the most basic and important parts of the guitar.

The quality of the tuning pegs directly affects the pitch. It is difficult to adjust the general tuning knobs to the right level. A little more makes it too high, a little less and it is too low. Bad quality tuning pegs face problem like too loose, too tight, or loosen up the strings easily. When use a good tuning pegs, even when the capo is used, it can rotate very smoothly and maintain precise pitch. Therefore, a good set of guitar tuning can greatly improve the performance and efficiency of the guitar. However, the quality of the tuning of many guitars is very average, so choosing and replacing a good tuning has become a task for more and more guitarists.

There are many different tuning pegs on the market, and their quality varies. Brands with High quality, good reputation, such as Rodgers，Garf，Gotoh, Sperzel, Waverly, Grover, Planet Waves, Kluson,  Schaller and Derjung are recommended.

This article is to discuss on knowledge about guitar tuning, and avoid buying bad tuning pegs, which will cause unnecessary problems in practice and performance.

There are many different names for the Tuning pegs: tuners, machine heads, head buttons, tuning keys, etc., which all refer to the parts located in the head section for fixing strings and tuning. In the early history of guitar evolution, the choice of tuning was very little. Fewer companies produced metal tunings. Most pipas (Chinese music instrument) and guitars used wooden tunings, just like those on violins. These tuning buttons are generally made of hardwood, which is not convenient to use. This allows the strings to slip easily, causing the instrument to run off the strings, causing headaches for the players.

Gear Ratio

When we are selecting tuning pegs we will see a parameter such as "18:1" or "1:18" specified by the manufacturer, called Gear Ratio.
The gear ratio in instrument tuners refers to how many turns of the tuning key equals a complete turn of the string post. In other words, a tuner with an 18:1 gear ratio means that you'd need to turn the tuner knob or button 18 times to make the string post go around one complete revolution. The higher the ratio, the higher the accuracy of the gears and the slight turning pitch will also change.

The number of numbers of gears of modern guitars is much higher than in the past. Some can get as high as 28:1. 14:1 and 18:1 are the most common ones.

Open guitar tuning pegs

Closed guitar tuning pegs

Locking Tuning Pegs 

Locking Guitar Tuning Machines hold your strings tight for positive, accurate tuning. If you want the best tuning pegs, the pegs with a lock are great options. When we push the string or use the crank, the tension on the string also changes. The string loop may not return to its original position when you loosen the string or crank. The more loops there are, the more likely it is that you will not be able to return the result is that the strings will go out of tune. The locked pegs can better prevent string running problems. The locking device on the pegs can prevent the strings from sliding, and at the same time, you don't have to wind the strings repeatedly on the pegs.

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How To Distinguish Left or Right Machine Heads

Refer to the images below : For a guitar that has all of the machines heads inline, left machine heads fit right-handed guitars and right machine heads fit left-handed guitars.
If looking at a machine head with the shaft facing away from you, the handle will be slight to one side of the shaft. If the handle is to the right of the shaft, then it is a right-handed machine head. If the handle is to the left of the shaft, then it is a left-handed machine head.