Listen to the intervallic relationship between each note in the scale as you play it. A scale is more than just a group of notes played in a specific sequence, but rather the embodiment of a particular tonal mood, or “mode” as recognized in musical terminology. Although this skill takes the longest to build, the ability to distinguish the sound of any given scale as it applies to the bass will give you, as a musician, a much greater understanding of how that scale relates to the tonality of the music as well as what the other musicians around you are playing. Listen to what you playing and you will gradually become more familiar with the sounds of different scales and how to employ them as opposed to just regurgitating a pattern. The result is an improvement in overall sound on your part, which is the ultimate goal for any bassist.
Write down, understand and memorize the interval construction of each scale. An interval is the distance between two notes and implies a movement in notation and frets on the bass. Every bass scale is constructed by combining various intervals to form a unique pattern; these intervallic arrangements are the essence of each scale’s sound and are responsible for providing the tonal distinction between them. Understanding the interval construction of each scale is synonymous with understanding the scale, so study and memorize the basic scales and their structure by writing them out and playing them on your instrument.
Recite and play the notes of the scale as you recognize them by their root note names. The musical alphabet consists of 12 notes, each having its own key along with subsequent scales that build off each note within that key. Simply put, any scale or pattern can be built on any one of those 12 notes; 12 options exist for each scale or pattern. For instance, 12 major scales exist and each one is built off one of the 12 notes: C major, C sharp major, D major, etc. Some of these scales have two different names, such as C sharp major, which can also be called D flat minor, the only difference being the first uses sharps and the latter, flats.
Learn and memorize the individual notes within each scale, their sequence and how they relate to the root note. For instance, C major consists of the notes C, D, E, F, G, A and B. gaining knowledge of note names presents many benefits, including faster fret board navigation, the ability to read music, and improved improvisation. Although this may seem like an immense amount of work, the task grows easier with each scale that is memorized; after that you will recognize patterns in the notes as well as comparisons that can be made between similar scales, as some scales have only one or two different notes.
Play the scales in various areas and positions of your instrument. The practical component of understanding a bass scale comes with physical knowledge of how to play and locate the pattern on the fret board or keyboard, which is the portion that most musicians tend to focus on. However, despite the importance of being able to play the scale, a scale is not simply a pattern to memorize. Conceive scales as sound patterns accessed on your specific instrument by finger patterns; remember, the scale will sound the same on other instruments. Record yourself playing each scale and listen to the recording to get the sound in your head.