!===============================================================! ! This document is the draft revised abc standard ! ! currently being discussed on the abcusers list. ! ! Other topics being discussed and not yet assimilated ! ! here include ! ! the V field (for specifying voices) ! ! the w field (for adding lyrics) ! ! extensions to the guitar chord feature ! ! Other topics which need to be addressed include ! ! dynamics ! ! extensions to first and second repeats ! ! Further suggestions should be posted to the ! ! abcusers list. ! ! ! ! Lines which have changed since the previous version ! ! of the standard are prefixed with a !. ! !===============================================================! This description of abc notation has been created for those who do not want to (or cannot) use the package ABC2MTeX but who wish to understand the notation. It has been generated semi- automatically from the ABC2MTeX userguide and so occasionally refers to other parts of the package. In particular, it mentions the document index.tex, a guide to using ABC2MTeX for archiving and indexing tunes, and to the example files English.abc, Strspys.abc and Reels.abc. It also refers to playabc, a separate package for playing abc tunes through the speaker of various machines. It is best read in conjunction with an introduction to abc notation available from http://www.gre.ac.uk/~c.walshaw/abc2mtex/INTRO.html ! Since the document was originally written a large number of abc ! packages (programs which either typeset the abc notation into ! standard notation or playback the abc through the speakers of ! a computer) have been developed. Not all of them follow this ! standard absolutely however and this document does at some points ! give hints about some of the more package specific features. Note that if you are intending to use the notation solely for transcribing tunes, you can ignore most of description of the information fields as all you really need are the T (title), M ! (meter), K (key), and possibly L (unit note length) fields. I have included a full description however, for those who wish to understand tunes transcribed by users of the package. Chris Walshaw C.Walshaw@gre.ac.uk ----------------------------------------------------------------- The abc Notation System ======================= Each tune consists of a header and a body. The header, which is composed of information fields, should start with an X (reference number) field followed by a T (title) field and finish with a K (key) field. The body of the tune in abc notation should follow immediately after. Tunes are separated by blank lines. Information fields ================== The information fields are used to notate things such as composer, meter, etc. in fact anything that isn't music. Most of the information fields are for use within a tune header but in addition some may be used in the tune body, or elsewhere in the tune file. Those which are allowed elsewhere can be used to set up a default for the whole or part of a file. For example, in exactly the same way that tunebooks are organised, a file might start with M:6/8 and R:Jigs, followed by some jigs, followed by M:4/4 and R:Reels, followed by some reels. Tunes within each section then inherit the M: and R: fields automatically, although they can be overridden inside a tune header. Finally note that any line beginning with a letter in the range A-Z and immediately followed by a : is interpreted as a field (so that line like E:|, which could be regarded as an E followed by a right repeat symbol, will cause an error). By far the best way to find out how to use the fields is to look at the example files (in particular English.abc) and try out some examples. Thus rather than describing them in detail, they are summarised in the following table. The second, third and fourth columns specify respectively how the field should be used in the header and whether it may used in tune body or elsewhere in the file. Certain fields do not affect the typeset music but are there for other reasons, and the fifth column reflects this; index fields only affect the index (see index.tex) while archive fields do not affect the output at all, but are just provided to put in information that one might find in, say, a conventional tunebook. Field name header tune elsewhere Used by Examples and notes ========== ====== ==== ========= ======= ================== A:area yes A:Donegal, A:Bampton B:book yes yes archive B:O'Neills C:composer yes C:Trad. D:discography yes archive D:Chieftans IV E:elemskip yes yes see Line Breaking F:file name yes see index.tex G:group yes yes archive G:flute H:history yes yes archive H:This tune said to ... I:information yes yes playabc K:key last yes K:G, K:Dm, K:AMix ! L:unit note length yes yes L:1/4, L:1/8 M:meter yes yes yes M:3/4, M:4/4 N:notes yes N:see also O'Neills - 234 O:origin yes yes index O:I, O:Irish, O:English P:parts yes yes P:ABAC, P:A, P:B Q:tempo yes yes Q:200, Q:C2=200 R:rhythm yes yes index R:R, R:reel S:source yes S:collected in Brittany T:title second yes T:Paddy O'Rafferty W:words yes W:Hey, the dusty miller X:reference number first X:1, X:2 Z:transcription note yes Z:from photocopy Some additional notes on certain of the fields:- T - tune title. Some tunes have more than one title and so this field can be used more than once per tune - the first time will generate the title whilst subsequent usage will generate the alternatives in small print. The T: field can also be used within a tune to name parts of a tune - in this case it should come before any key or meter changes. K - key; the key signature should be specified with a capital letter which may be followed by a # or b for sharp or flat respectively. In addition, different scales or modes can be specified and, for example, K:F lydian, K:C, K:C major, K:C ionian, K:G mixolydian, K:D dorian, K:A minor, K:Am, K:A aeolian, K:E phrygian and K:B locrian would all produce a staff with no sharps or flats. The spaces can be left out, capitalisation is ignored for the modes and in fact only the first three letters of each mode are parsed so that, for example, K:F# mixolydian is the same as K:F#Mix or even K:F#MIX. There are two additional keys specifically for notating highland bagpipe tunes; K:HP doesn't put a key signature on the music, as is common with many tune books of this music, while K:Hp marks the stave with F sharp, C sharp and G natural. Both force all the beams and staffs to go downwards. Finally, global accidentals can also be set in this field so that, for example, K:D =c would write the key signature as two sharps (key of D) but then mark every c as natural (which is conceptually the same as D mixolydian). Note that the there can be several global accidentals, separated by spaces and each specified with an accidental, __, _, =, ^ or ^^, (see below) followed by a letter in lower case. Global accidentals are overridden by accidentals attached to notes within the body of the abc tune and are reset by each change of signature. ! L - unit note length; i.e. L:1/4 - quarter note, L:1/8 - ! eighth note, L:1/16 - sixteenth, L:1/32 - thirty-second. If ! there is no L: field in the header, a unit note length is set ! by default, based on the meter field M: (see below). M - meter; apart from the normal meters, e.g. M:6/8 or M:4/4, ! the symbols M:C and M:C| give common time (4/4) and cut time (2/2) ! respectively. The symbol M:none omits the meter entirely (free ! meter). P - parts; can be used in the header to state the order in which the tune parts are played, i.e. P:ABABCDCD, and then inside the tune to mark each part, i.e. P:A or P:B. ! Within the header, a part can be repeated by following it ! with a number e.g. P:A3 is equivalent to P:AAA and a ! sequence can be repeated by using parentheses e.g. P:(AB)3 is ! equivalent to P:ABABAB. Nested parentheses are permitted ! and dots may be placed anywhere within the header P: field, ! e.g. P:((AB)3.(CD)3)2, to increase legibility and are ignored. ! Q - tempo; defines the beat unit (and beats per minute) for setting tempo, ! e.g. Q:1/2 means that a half note counts as one beat. The number of beats per ! minute can be specified, e.g. Q:1/2=120 means 120 half-note beats per ! minute. If no beat unit is given, one is set by default (see ! below). G - group; to group together tunes for indexing purposes. H - history; can be used for multi-line stories/anecdotes, all of which will be ignored until the next field occurs. abc tune notation ================= The following letters are used to represent notes:- d' -c'- ---- b -a- --- ---- ---- g ------------------------------------f------------------- e --------------------------------d----------------------- c ----------------------------B--------------------------- A ------------------------G------------------------------- F --------------------E----------------------------------- D ---- ---- ---- -C- B, ---- -A,- G, and by extension, the notes C, D, E, F, a' and b' are available. Notes can be modified in length (see below). ! Lower octaves are reached by using 2 commas, 3 commas and so on. ! Higher octaves are written using 2 apostrophes, 3 apostrophes and ! so on. Rests ===== Rests are generated with a z and can be modified in length in exactly the same way as notes can. Note lengths ============ ! NB Throughout this document note lengths are referred as sixteenth, eighth, ! etc. The commonly used equivalents are sixteenth note = semi-quaver, eighth ! = quaver, quarter = crotchet and half = minim. ! The unit note length for the transcription is set in the L: field, e.g. ! L:1/8 sets an eighth note as the unit note length. A single letter in the ! range A-G, a-g represents a note of this length. For example, if the unit ! note length is an eighth note, DEF represents 3 eighth notes. ! Notes of differing lengths can be obtained by simply putting a multiplier ! after the letter. Thus if the unit note length is 1/16, A or A1 is a ! sixteenth note, A2 an eighth note, A3 a dotted eighth note, A4 a quarter ! note, A6 a dotted quarter note, A7 a double dotted quarter note, A8 a half ! note, A12 a dotted half note, A14 a double dotted half note, A15 a triple ! dotted half note and so on. If the unit note length is 1/8, A is an eighth ! note, A2 a quarter note, A3 a dotted quarter note, A4 a half note, and so ! on. ! To get shorter notes, either divide them - e.g. if A is an eighth note, A/2 ! is a sixteenth note, and A/4 is a thirty-second note - or change the unit ! note length with the L: field. Alternatively, if the music has a broken ! rhythm, e.g. dotted eighth note/sixteenth note pairs, use broken rhythm ! markers (see below). Note that A/ is shorthand for A/2 and similarly A// ! = A/4, etc. ! If no unit note length is given explicitly in the L: field, a unit note ! length is set by default, based on the meter. This default is calculated by ! computing the meter as a decimal: if it is less than 0.75 the default unit ! note length is a sixteenth note; if it is 0.75 or greater, it is an eighth ! note. For example, 2/4 = 0.5, so, the default unit note length is a ! sixteenth note, while for 4/4 = 1.0, or 6/8 = 0.75, or 3/4= 0.75, it is an ! eighth note. For M:C (4/4), M:C| (2/2) and M:none (free meter), the default ! unit note length is 1/8. Broken rhythms ============== A common occurrence in traditional music is the use of a dotted or broken rhythm. For example, hornpipes, strathspeys and certain morris jigs all have dotted eighth notes followed by sixteenth notes as well as vice-versa in the case of strathspeys. To support this abc notation uses a > to mean `the previous note is dotted, the next note halved' and < to mean `the previous note is halved, the next dotted'. Thus the following lines all mean the same thing (the third version is recommended): L:1/16 a3b cd3 a2b2c2d2 L:1/8 a3/2b/2 c/2d3/2 abcd L:1/8 a>b c> means that the first note is double dotted and the second quartered and >>> means that the first note is triple dotted and the length of the second divided by eight. Similarly for << and <<<. Duplets, triplets, quadruplets, etc. ==================================== These can be simply coded with the notation (2ab for a duplet, (3abc for a triplet or (4abcd for a quadruplet, etc., up to (9. The musical meanings are: (2 2 notes in the time of 3 (3 3 notes in the time of 2 (4 4 notes in the time of 3 (5 5 notes in the time of n (6 6 notes in the time of 2 (7 7 notes in the time of n (8 8 notes in the time of 3 (9 9 notes in the time of n If the time signature is compound (3/8, 6/8, 9/8, 3/4, etc.) then n is three, otherwise n is two. More general tuplets can be specified using the syntax (p:q:r which means `put p notes into the time of q for the next r notes'. If q is not given, it defaults as above. If r is not given, it defaults to p. For example, (3:2:2 is equivalent to (3::2 and (3:2:3 is equivalent to (3:2 , (3 or even (3:: . This can be useful to include notes of different lengths within a tuplet, for example (3:2:2G4c2 or (3:2:4G2A2Bc and also describes more precisely how the simple syntax works in cases like (3D2E2F2 or even (3D3EF2. The number written over the tuplet is p. Beams ===== To group notes together under one beam they should be grouped together without spaces. Thus in 2/4, A2BC will produce an eighth note followed by two sixteenth notes under one beam whilst A2 B C will produce the same notes separated. The beam slopes and the choice of upper or lower staffs are generated automatically. Repeat/bar symbols ================== Bar line symbols are generated as follows: | bar line |] thin-thick double bar line || thin-thin double bar line [| thick-thin double bar line :| left repeat |: right repeat :: left-right repeat First and second repeats ======================== First and second repeats can be generated with the symbols [1 and [2, e.g. faf gfe|[1 dfe dBA:|[2 d2e dcB|]. When adjacent to bar lines, these can be shortened to |1 and :|2, but with regard to spaces | [1 is legal, | 1 is not. Accidentals =========== The symbols ^ = and _ are used (before a note) to generate respectively a sharp, natural or flat. Double sharps and flats are available with ^^ and __ respectively. ! Changing key, meter, and unit note length mid-tune ================================================== ! To change key, meter, or unit note length, simply put in a new line with a K: M: or L: field, e.g. ed|cecA B2ed|cAcA E2ed|cecA B2ed|c2A2 A2:| K:G AB|cdec BcdB|ABAF GFE2|cdec BcdB|c2A2 A2:| To do this without generating a new line of music, put a \ at the end of the first line, i.e. E2E EFE|E2E EFG|\ M:9/8 A2G F2E D2|] ! A meter change within the body of the tune will not change the ! unit note length (unlike one in the header where no L: field is ! present). Ties and slurs ============== You can tie two notes together either across or within a bar with a - symbol, e.g. abc-|cba or abc-cba. More general slurs can be put in with () symbols. Thus (DEFG) puts a slur over the four notes. Spaces within a slur are OK, e.g. (D E F G), but the open bracket should come immediately before a note (and its accents/accidentals, etc.) and the close bracket should come immediately after a note (and its octave marker or length). Thus (=b c'2) is OK but ( =b c'2 ) is not. Gracings ======== ! Grace notes can be written by enclosing them in curly braces, {}. For ! example, a taorluath on the Highland pipes would be written {GdGe}. The ! tune `Athol Brose' (in the file Strspys.abc) has an example of complex ! Highland pipe gracing in all its glory. Although nominally grace notes ! have no melodic time value, expressions such as {a2} and {a>b} can be ! useful and are legal although some packages may ignore them. ! The unit duration to use for gracenotes is not specified by the abc ! file, but by the package, and might be a specific amount of time ! (for playback purposes) or a note length (e.g. 1/32 for Highland pipe ! music, which would allow {ge4d} to code a piobaireachd 'cadence'). ! The presence of gracenotes is transparent to the broken rhythm ! construct. Thus the forms A<{g}A and A{g}, (e.g. roll, staccato marker or up/downbow), , , , , i.e. ~^c'3 or even "Gm7"v.=G,2 Tie symbols, -, should come immediately after a note group but may be followed by a space, i.e. =G,2- . Open and close chord symbols, [], should enclose entire note sequences (except for guitar chords), i.e. "C"[CEGc] or "Gm7"[.=G,^c'] and open and close slur symbols, (), should do likewise, i.e. "Gm7"(v.=G,2~^c'2) ! Metrical beats for setting tempo ! ================================ ! The standard form of the Q field is, for example, Q:1/2=120 which means ! 120 half-note beats per minute, however, if a beat unit is given without ! a speed (e.g. Q:3/8), then the speed is usually intended to be set in ! a playback program and this field will then be ignored by typesetting ! programs. ! The beat unit can also be given as a multiple of the unit note length using the ! letter L, e.g. if L:1/8, then Q:L3=120 is equivalent to Q:3/8=120. However, ! it is usually better to specify an absolute note length. (Note that giving ! a tempo in relative to the unit note length may result in unexpected ! behaviour if the unit note length is changed, either explicitly or by ! default mechanisms.) Older versions of the abc standard used the letter C ! instead of L, and this is still a permitted form although not recommended. ! If no beat unit is set in the Q: field or if the Q: field is missing, a ! default beat unit is assumed. The default beat unit is the demoninator of ! the meter, except for compound meters (6/8, 9/8 and higher multiples of ! 3/8), for which the default beat unit is 3/8. For example, if M:2/4, the ! default beat unit is 1/4. For M:C| (=M:2/2) it is 1/2; for M:12/8 it is ! 3/8. ! When giving a tempo, it is preferable to specify a beat unit rather than to ! rely on default mechanisms. Comments ======== A % symbol will cause the remainder of any input line to be ignored. The file English.abc contains plenty of examples. New notation ============ The letters H-Z can be used to define your own new notation within a tune. Currently the way they are implemented (if at all) is extremely package dependent and so users are advised not to rely too heavily on them to include new features. Instead, if there is a feature or symbol that you need and which is not available it is better to press for it to be included as a part of the language. Line breaking and justification =============================== Generally one line of abc notation will produce one line of music, although if the music is too long it will overflow onto the next line. This can look very effective, but it can also completely ruin ties across bar lines, for example. You can counteract this by changing either the note spacing with the E: field (although currently this is package dependent) or break the line of abc notation. If, however, you wish to use two lines of input to generate one line of music (see, for example, the `Untitled Reel' in Reels.abc) then simply put a \ at the end of the first line. This is also useful for changing meter or key in the middle of a line of music. With most packages lines of music are right-justified. However, where this is not the case (e.g. when using MusicTeX), a * at the end of each line of abc notation will force a right-justified line-break.