The bassline is an essential element in contemporary music, but what exactly is it, and what role does it perform? In the first of a new series, Simon Trask sets out to discover what makes the bassline tick...

The old adage that there's nothing new under the sun certainly applies to the bassline - or, more accurately, the bass line. Back in the seventeenth century, keyboard accompanists played from a system of notation known as 'figured bass', in which only the bass part was written out on the page. The bass notes had numbers written beneath them in the score which indicated the intervals - and therefore the harmony - to be played.

This period in European music, known as the Baroque period, marked a fundamental transition in musical style. Out went the old polyphonic style in which all musical parts contributed more or less equally to the fabric of the music, in came the new homophonic music, in which the highest (soprano) and lowest (bass) parts assumed prominence and the 'inner' parts became the chordal harmony accompaniment.

This transition marked the beginning of Western music as we know it today, with its melodies, harmonies and basslines - and the bass line was its foundation-stone.

Okay, that's enough of the history lecture! Can we define what a bassline actually is? In simple terms, it's a series of low-pitched notes - preferably having some kind of continuity! What is the function of a bassline, then - if indeed it only has one function? Perhaps the best catch-all answer is that the bassline is there to underpin the music - ie. to support it from below, to act as the solid foundation on which the rest of the music is built.

The simplest way in which it can do this is to play, and therefore reinforce, the root note of each chord. Which brings us to Example 1 and, yes, music notation. We'll be using what is known as the 'bass clef' in our examples, as this is the clef which (reasonably enough) is used to indicate pitches in the bass range.

For those of you new to music notation, I'll provide an explanation which should be enough to get you started in reading the examples. However, if you decide that you want to take things a bit further (and that might be a good idea), it is perhaps time to take the plunge and buy a book on music theory (gulp!). A book I'd recommend - because it's both fun to read and easy to digest - is keyboard player Dave Stewart's Introducing the Dots: Reading and Writing Music for Rock Musicians, published by Blandford Press.

Anyway, let's get on with our basic rundown, using the notated examples as a reference. The group of parallel lines on which the notes are inscribed is known as a 'stave', and the curvy symbol at the beginning of the stave is known as the 'bass clef. The two numbers to the right of the clef are known as the 'time signature'. Most Western popular music is in 4/4 time, which means there are four crotchets, or quarter-notes, to the bar.

The vertical lines on the stave are known as 'bar lines'; these break the music up visually in accordance with the time signature (eg. every four crotchet beats for 4/). In this way you can refer to locations in written music (as in "let's start playing from bar 17").

Each line and space of the stave indicates a musical pitch. Reading from bottom to top, the lines indicate pitches in the rising sequence G, B, D, F, A (the A being the first A note below middle C). The spaces inbetween indicate the pitches inbetween, ie. A, C, E, G. In Example 1, the notes are 4xC, 4xF, 4xG, and 4xF again - with all notes having the same duration. This is the basic four beats to the bar in 4/4 time. The letters above the notes indicate the chord, or harmony, which the bass note underpins - respectively C major, F major, G major, and F major again.

You can see from Example 1 that the bass plays the root note of each chord (eg. C in C major, which is made up of the notes C, E and G). In other words, it reinforces the 'foundation' of the chord. For a bouncy r'n'b feel, play the notes staccato (ie. 'clipped') at an upbeat tempo, together with a simple alternating kick and snare rhythm on quarter-notes.

Incidentally, when bass guitarists read the bass clef the notes they actually play are an octave lower than notated. Keyboard players, on the other hand, read the bass clef as notated, unless the notated music specifically indicates otherwise. In these examples I'd suggest you follow the bass guitarist's practice, as we're in bass pitch territory.

In Example 2, the bass part is still confined to playing the root note, but this time with octave jumps and a faster rhythm. These notes are known as quavers, or eighth-notes ie. there are eight to the bar - count 'em. Now we're into disco territory. The insistent root-note repetition and pulsing rhythm is characteristic of this style.

By the way, the lines below the stave are known as 'leger lines'. As you can see, they act as an extension of the stave; counting down from G (the bottom line of the stave), the notes are F, E, D and C (which in this case is the note being played).

Example 3 takes this a stage further by replacing each high eighth note with two sixteenths. This gives the bassline an even more insistent feel than the previous example.

Which brings me to my next point, which is that rhythm is an important aspect of a bassline. Even if you play one bass note per bar, that needs to be a conscious decision based on the tempo of the music and what the other parts are doing rhythmically - especially the drums. Related to rhythm is the concept of motion. All music has a sense of motion to it, and you need to be sensitive to how the rhythm of your bassline propels the music forward.

Let's consider what other notes we can work into a bassline, because playing the root note all the time can get kind of boring! In Example 4, the bass 'outlines' the harmony in each bar by playing the notes of each chord eg. C E G for C major. This still reinforces the harmony, but works a bit more melodic interest into the bassline.

To close this month, an example of what's known as an ostinato bass (see Example 5). Here, the bassline keeps playing the same sequence of notes while the harmony changes over it.