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Because bass guitars are electric, the body of the guitar can come in nearly any shape or color and still give a great sound. What is important though, is choosing a guitar with the right number of strings for your ability. As a beginner, it is best to start with a classic 4-string bass guitar. The original bass guitar was made with 4 strings, and is considered the most basic. Nearly all bass guitar music can be played on a 4-string guitar, and because the neck is narrower than a 5 or 6 string guitar, it is easier to work your hands around. A 4-string guitar is typically strung with the EADG strings, but if you want, it can be strung like a 5-string guitar with a lower string making it BEAD instead. 5-string and 6-string guitars are great because they give a greater range of available notes to play. However, they also require more control to reduce the buzzing of other strings and the ability to reach all the notes. The scale of a bass guitar refers to the distance from the nut to the bridge, essentially the length of the guitar strings. A longer scale will have longer string length and produce a deeper sound. A shorter scale may be easier to maneuver for a beginner, but will lack the depth of sound a long scale bass will have. Most bass guitars have a 34" scale, but you can also find short scale (30" or less), medium scale (30"-33:), and extra long scale (35" or more) bass guitars. Unless your hands are very small or very large, stick with a 34" scale for the best sound. If you decide to get a 5-string or 6-string bass guitar, increase the scale for a better sound. Always get a minimum 35" scale if you increase the number of strings. Frets are the metal dividers in the fingerboard. Frets mark where different notes on a string can be played (by pushing a string against it), and are found on all guitars. However if you are buying a bass guitar, you have the option to go fretless. A fretless guitar does not have the metal dividers, and instead has a long, smooth fingerboard. Fretless guitars are more difficult to play because you don't have a visual marker of where certain notes lie. Instead, you have to play the bass by ear. For beginners, it is best to choose a guitar that is fretted, to give some guidelines for note and finger placements. Over time, you can choose to move to a fretless guitar for a bigger challenge and a slightly different sound. Bass guitars are made out of many different materials, including different types of hard and soft woods, and composite or synthetic materials. Although each material gives the bass a slightly different appearance and sound, as long as the instrument is solid and well built, the material the bass is made from isn't an major factor to choosing your bass. Either way, here are some characteristics of different materials. Hard woods, such as hard maple, walnut, ebony, and rosewood, give a percussive sound to your bass. Soft woods including alder, basswood, and swamp ash, aid in supplying your bass with a softer, warm sound. The most popular synthetic material to make bass guitars out of is graphite, although luthite is another commonly used material. These are all very consistent in mass production, as the material doesn't change from guitar to guitar like it does with natural woods. Many bass guitars are made from a mix of materials, especially having the body of one material and the fingerboard of another. This is a good option as well, so don't feel the need to search for a single-material bass only. . In order to play bass, you need to have an amp to plug your bass, so that you can hear yourself play. An amp has three main components: the power amp, preamp, and speaker cabinet. The easiest way to get all three is to buy a combo amplifier. Although these may lack the power for a louder sound of bigger amps, they are very easy for beginners to use. The biggest advantage of having separate pieces of gear, is that you can choose each one to match your personal taste. You should start with a small combo amp, if you find the need to upgrade it later on your bass journey, you will know better what to look for on a higher-end amplifier. Playing with fingers gives the "traditional" bass sound, and allows for many finger exclusive techniques, while playing with a pick will make the sound brighter and more agressive (hence many rock/metal players use them), allowing for more guitar-like techniques. Many people recommend to learn to play both ways, you'll be a more versatile player overall.
Choose the number of strings. Select a scale. Decide on fretted or fretless. Choose a material. Find an amp Decide if you'll play with your fingers or with a pick.