> ## Documentation Index > Fetch the complete documentation index at: https://chart-spec.enchor.us/llms.txt > Use this file to discover all available pages before exploring further. # Instrument sections > The section names for each instrument and difficulty, and their note values. Each instrument section holds one track: the notes, modifiers and phrases of one instrument at one difficulty. ```text theme={null} [ExpertSingle] { 768 = N 0 0 768 = N 1 0 960 = N 2 192 960 = S 2 768 1152 = N 3 0 } ``` ## Section names A section's name is a difficulty followed by an instrument, such as `ExpertSingle` for Expert guitar. The difficulties are `Easy`, `Medium`, `Hard` and `Expert`. | Instrument in the name | Instrument | Kind | | - | - | - | | `Single` | Lead guitar | 5-fret | | `DoubleGuitar` | Co-op guitar | 5-fret | | `DoubleBass` | Bass guitar | 5-fret | | `DoubleRhythm` | Rhythm guitar | 5-fret | | `Keyboard` | Keys, played on a guitar controller | 5-fret | | `Drums` | Drums | Drums | | `GHLGuitar` | 6-fret guitar | 6-fret | | `GHLBass` | 6-fret bass | 6-fret | | `GHLRhythm` | 6-fret rhythm guitar | 6-fret | | `GHLCoop` | 6-fret co-op guitar | 6-fret | | `GHLKeys` | 6-fret keys | 6-fret | A scanner matches names exactly, in the letter case shown. **Edge case: names close to these.** Clone Hero checks only some of a name's characters, so it reads a few other names as instrument sections: `[ExpertSingl]` is Expert guitar there. YARG's chart loader adds `[ExpertDoubleDrums]` to Expert drums when the file also has `[ExpertDrums]`. YARG's song list and scan-chart match names exactly. ## Notes A note is an `N` event: ```text theme={null} = N ``` The value says which note it is, and depends on the kind of instrument. The length is the note's sustain, in ticks: the note is held from its tick to `tick + length`. A length of 0 means no sustain. ### 5-fret | Value | Note | | - | - | | `0` | Green | | `1` | Red | | `2` | Yellow | | `3` | Blue | | `4` | Orange | | `7` | Open: strummed with no fret held | `N 5` and `N 6` are modifiers, not notes. See [Note modifiers](/chart/modifiers). ### 6-fret The 6-fret frets are in two rows: three black frets on top and three white frets below them. | Value | Note | | - | - | | `0` | White 1 | | `1` | White 2 | | `2` | White 3 | | `3` | Black 1 | | `4` | Black 2 | | `7` | Open | | `8` | Black 3 | `N 5` and `N 6` are modifiers, as on 5-fret. See [Note modifiers](/chart/modifiers). ### Drums | Value | 4-lane and pro | 5-lane | | - | - | - | | `0` | Kick | Kick | | `1` | Red | Red | | `2` | Yellow | Yellow | | `3` | Blue | Blue | | `4` | Green | Orange | | `5` | Green tom, in a pro chart. See [Drum types](/chart/drums#drum-types) | Green | | `32` | Double kick | Double kick | [Drums](/chart/drums) gives the kinds of drum chart, and the modifiers for cymbals, accents, ghosts and flams. ## Notes at one tick * Notes of different values at one tick form a chord. Each note of a chord keeps its own length, so a chord's sustains can end at different ticks. * An open note may be in a chord with fret notes. The player holds the fret notes and strums. * **Required:** one note of each value at most at a tick. ## Range shifts A range shift tells the player which frets a stretch of one 5-fret difficulty uses, so that their hand can move with the notes. It's an `E` event in the section of that difficulty, on guitar, co-op guitar, bass, rhythm guitar or keys: ```text theme={null} = E ld_range_shift = E ld_range_shift ``` | Part | Values | | - | - | | Difficulty | `0` Easy, `1` Medium, `2` Hard, `3` Expert: the difficulty of the section the event is in | | Position | The lowest fret of the range, where the index finger goes: `1` green to `5` orange | | Size | The number of frets in the range, from `1` to `5`. Without it, the size is 3 on Easy, 4 on Medium, and 5 on Hard and Expert | ```text theme={null} [EasySingle] { 0 = E ld_range_shift 0 1 3 3072 = E ld_range_shift 0 3 } ``` Here Easy guitar uses green, red and yellow from tick 0, and yellow, blue and orange from tick 3072. * **Required:** a position and size that end at orange or before: the position plus the size is no more than 6. * **Required:** the parts separated by single spaces, and the numbers in digits without a sign, with no brackets or quotation marks around the text. The difficulty is the section's, and the position and size are each from 1 to 5. Range shifts go only in 5-fret sections. * A range shift lasts from its tick until the next range shift of its section. Before the first one, all five frets are in range. * **Recommended:** one range shift at most at a tick. **Edge case:** of two range shifts at one tick, a scanner uses the later one in the file. ## Tracks A section is a track only if it holds at least one note. [How notes resolve](/chart/note-resolution) says how a scanner turns a section's notes into the notes a player plays. **Edge case: a section without notes.** A section with only modifiers, phrases or text events is allowed, for example while a charter copies phrases to every difficulty before charting its notes. It isn't a track: a scanner doesn't list it, and it gets no [hash](/hashes/btrack#which-tracks-have-one). scan-chart reports it as a warning. ## Ignored * **An `N` value that the tables don't list** for the section's instrument, such as `N 8` in a 5-fret section. * **A section with any other name.** Older games used names such as `ExpertSingleBass` and `ExpertDoubleDrums`. ## Invalid forms A scanner ignores it. That includes another spelling, letter case or spacing, square brackets, a sign before a number, and a size of 0. It also includes a difficulty other than the section's, a position or size outside 1 to 5, a position and size that add up to more than 6, and a range shift outside a 5-fret section. A range shift in quotation marks is read as one without them: see [Syntax](/chart/syntax#invalid-forms). scan-chart keeps the text, and writes it back. A scanner uses the note with the longer sustain, as Clone Hero and scan-chart do. YARG uses the one written first. On guitar, it counts the two as a chord when it decides strums and HOPOs, so the note is a strum there unless a modifier changes it. When scan-chart saves an edited song, it removes a line written twice, and keeps notes of different lengths as written. This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.