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Realistic Guitar Tracking Pt II: Guitar Theory for Trackers

Realistic Guitar Tracking Pt II: Guitar Theory for Trackers

Postby FingerSoup » Tue Mar 23, 2010 10:30 am

Realistic Guitar Tracking Pt II: Guitar Theory for Trackers

By: FingerSoup

In order to track realistic guitar, one needs to understand how guitars work. Some of this seems simple enough, but some of the intuitiveness and patterned nature of the guitar doesn't exatly translate well to Piano. For instance, On a guitar, most people play a G Major chord with all 6 strings. On piano it's 3 keys. Likewise, there are several techniques one can use on a guitar, such as hammer-ons, Pull-offs, slides, string bends, and pre-bending. Likewise, If you are using one of a million different chord-finders on the Internet, you may want to know what notes are actually involved. This tutorial is intended to teach you how guitars work, how to convert popular guitar notation to notes relevant to any medium, and how to recreate guitar-like sound in a tracker.

Guitar Basics

The guitar, much like a piano, is a percussive stringed insrument. When you hit a string, the string vibrates and sound is produced. The only real difference is that with a guitar, you interact directly with the sound-producing strings, whereas with a piano you must use tools such as keys and pedals. The richness in sound that is lost by using only one string per note (or 2 in the case of a 12-string guitar) is made up for with the ability to manipulate the tone by interacting with the strings directly.

A guitarist finds their notes on the fret board. When you press the string down between the frets, you adjust that string's note by a semitone per fret. Thus if the string you pluck is tuned to E, the 3rd fret will be G. Each fret is ALWAYS a semitone.

As a result, this makes the guitar a patterned instrument... This means similar finger placements (Chord shapes) produce the same dynamic as you move up and down the fret board. For instance, if you need to change the key of a song, you can add a device called a capo (it presses down all the strings on a single fret) anywhere on the neck and play the song using the same chord shapes. no need to do tricky transposing. Barre chords are similar to using a capo. You use your index finger to barre across the neck and use simple chord shapes to pick your chord. you can then move this entire shape up and down the neck to get the chord you'd like.

The Strings, and Standard Tuning

Guitarists don't make describing this easy for you. The bottom and top are referred to in a MUSICAL sense, not a geographic one. the best way to explain this, is with a diagram:

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right-handed Guitar viewed from the front.
  _____   ___
 /     \_/   \    Lowest or
|             |   Bottom string
|  top end  ===============|XXX    Bottom end
|  of Neck  ===============|XXX    of neck
|       _   \    Highest or
 \_____/ \___\   Top String

The lowest string (the fattest bassiest string) is Low E. The next string is A, which is 5 semitones up. each string is 5 semitones up from the last, with the exception of the B string. thus, the tuning is as follows:

Low E, A, D, G, B, High E (Represented henceforth with a lower case E).

Each fret on the neck, is as I mentioned, one semitone per fret. thus, all you need to convert from fret to note, is count your frets, and add that many semitones to the tuned note of the string.

Examining Guitarist Notations

if you're looking to find some authentic guitar chords to arpeggio, or a riff to copy, to build up your inner guitarist instincts, here's how to read the music.. There are 2 kinds of notations that are specifically designed for guitarist use. the first is Chord charts, the second is Tablature. both forms are scattered all over the web..

Chord charts are just a diagram of the neck of a guitar. they usually look as such:

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Tuning: Standard tuning - (low to High) EADGBe

D Major


Strings are shown left to right as if the guitar was standing with the neck of the guitar vertical. strings are tuned per the tuning legend. Standard guitar tuning shown above is most common, but there are hundreds of tunings in use today. Anywhere on the fret board where a dot appears, is which strings to press. These dots are sometimes marked with numbers so as to indicate which fingers to use (1 for index, 2 for middle, 3 for ring, 4 for pinky)

A thick black bar or double bar, represents the nut, or the placement of the capo. x'es above the fret board mean that that string is not played. An X on the fret board means place a finger on the string to mute it at that position. O's above the string mean that the string is to be played open - strummed without a finger on it.

Next is Tablature, or Tab for short. Tablature is usually accompanied by Sheet music, and is designed to show fingerings for an entire song, not just a single chord.

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The lines are laid out as if the strings were horizontal. Tuning is marked on the right, or as seen in magazines, in a legend above the song. It should always be laid out per the above guitar diagram. The bottom string is closest to the top of the page.

Time passes in tab as you move right. Usually there will be an indication as to whether you should be using an up-stroke, or a down-stroke in your strum, or at the very least, have musical notation to notify you of timing. If it's on the internet though, often these are omitted, and you are left to guess, or listen along.

Tablature can also show sliding, bending, pre-bending, hammer-ons and pull-offs... Most Magazines have standard ways of showing these things. Internet tab is slightly different, depending on the author, their software, etc... as most Internet tab is essentially done with ASCII art similar to the above examples.

Basic Playing Techniques, and Notation

Hammer-ons and Pull offs
A Hammer-on is when you percussively press a string into the fret board to make or change the note being played. It is usually used as a transition to a higher note on the same string, but in some cases can also be used to transition to a note on a different string. The latter usually causes a sub-standard sound, and thus is typically done in fast runs only.

A Pull-off is the opposite. It is when you remove a finger from the fret board to change the note to a lower tone. Pull-offs can only be done on the same string (You can't pull your finger off of a string that you haven't placed on the fret board). it is permissible to do a slight pluck of the string with the removing finger in order to keep the volume of the note strong.

Hammer-ons and pull-offs in print, are usually represented by slurs in musical notation and Tab. For Internet based tab, you will see "h" and "p" between closely placed notes. It will look as such:

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Tracking hammer-ons and pull-offs is actually pretty easy. If you use a note offset to cut the pluck out of a note, and preferably cut it to a similar point in the waveform (for like volume), you will usually come up with a relatively authentic sound.

Slides are where you move from one note to another, by sliding your finger up or down the fretboard, without releasing pressure on the string. They are often represented with a diagonal line indicating the direction of movement. On internet tab, these are often shown with slash and backslash. It is also permissible to slide in from, or out to no note at all. Technically speaking, it is a glissando.

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Applying these concepts to trackers are simple, if you have a "glide to" function in your tracker. play the first note, then glide-to the second. When gliding in from nowhere, or out to nowhere, Often one must pick an arbitrary note to glide to or from, as the speed of the glide is more important than the starting or ending tone. It is also a good idea to mute or fade out the final tone of a slide to nowhere, otherwise it wouldn't be to nowhere. This of course depends on your sample.

String Bending and pre-bending

String bends are when you pluck a note, then alter the pitch in a portamento, by pulling or pushing the string sideways across the fretboard with your fretting hand. These bends are marked in print, by curved arrows. These curved arrows start horizontal, and curve up. These arrows are often marked with the amount of a semitone to bend. This means that half-semitones are possible in the bending process. On the internet you may see a b marked between approximate pitch values, or one might find some other proprietary way of marking these.

pre-bend is when the string is bent before plucking the string. It is marked by a curved arrow, that goes from horizontal, to point down. It is usually preceeded by a bend up. In some cases, where there is no audible bend up, there will be a perpindicular arrow indicating the amount of pre-bend to apply, followed by the arrow down to the fret to be played after the bend is complete.

All pre-bends, and some regular bends can be done with the glide-to features, but in many cases, a careful open-ended portamento is required for half-semitones for a bend. Blind prebends from half-semitones will often not be possible, unless you can do a pitch offset when you trigger the note, then reliably glide-to the finishing note.
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