Stradella bass system

src: accordionmusic.info

The Stradella Bass System (sometimes called standard bass) is a buttonboard layout equipped on the bass side of many accordions, which uses columns of buttons arranged in a circle of fifths; this places the principal major chords of a key (I, IV and V) in three adjacent columns. In a typical layout, as pictured, each column contains, in order:

• The major third above the root ("counter-bass")
• The root note
• The major chord
• The minor chord
• The dominant seventh chord
• The diminished seventh chord

Video Stradella bass system

Layout

The following chart shows a common 120-button Stradella layout.

Each bass note, and each pitch in a chord, is usually sounded simultaneously in multiple octaves. Larger accordions offer some control over the voicing with register switches.

In modern accordions, each chord button sounds three individual pitches. Early accordions sounded four pitches for the seventh and diminished chords. Modern Stradella systems omit the 5th from these two chords, allowing for more versatility. For example, an augmented seventh chord can be created by using the dominant seventh chord button and adding an augmented 5th from the right-hand manual or from one of the bass or counterbass buttons.

In most Russian layouts the diminished seventh chord row is moved by one button, so that the C diminished seventh chord is where the F diminished seventh chord would be in a standard Stradella layout; this is done in order to achieve a better reachability with the forefinger.

As the buttons are on the front face and cannot be seen by the player, an aid to navigation is provided by a small depression, hole or bump on the central C button in the root row, often supplemented by similar or different tactile marks on other selected root-bass buttons, such as the A? and E four buttons away in either direction.

Maps Stradella bass system

Notation

When naming chord buttons, major chords are often suffixed with "M", for example "CM", to distinguish them from bass notes.

In staff notation, notes below the center of the bass-clef staff are bass notes, and notes above the center of the staff usually indicate chord buttons, labeled as necessary with "M", "m", "7", or "d" or "dim". (Repeated chords are usually only labeled on the first instance.)

Within this convention, the written octave for bass notes is arbitrary, as the Stradella system does not have buttons for higher and lower octaves.

An example:

Bass notes to be played on the major third (counterbass) row are indicated by repurposed "tenuto" lines below the notes (as in the E bass note in the example above), or underlined note names or numbers.

Single-note bass lines are often labeled "B.S." (bass solo or bassi soli), especially when they extend above the middle of the staff.

src: forex.today

Fingering

As with the piano, fingers are numbered 2 to 5, starting with the index finger, mirroring right-hand fingering. As a rule, the thumb, numbered 1, is not used.

Patterns can be played identically in any desired key, changing only the starting position; this is because unlike a piano keyboard, the Stradella layout does not distinguish between "white notes" and "black notes". Layouts with 16 or more columns are sufficient to play in any of the 12 keys of the circle of fifths.

Bass and chords

4-3 is a recommended fingering for a bass note and its corresponding major chord (e.g. C-CM-C-CM). For alternate bass with the root and fifth, 4-3-2-3 can be used for major chords (e.g. C-CM-G-CM), 4-2-3-2 for minor and other types of chords (e.g. C-C7-G-C7).

Scales

Scales, runs, and other bass lines are played on the bass note buttons, the row or rows closest to the bellows (root row, optional thirds row, optional minor thirds row).

Major scales

The major scale can be fingered without stretching the hand, playing in any key as r4 r2 t4 r5 / r3 t5 t3 r4 (r = root row, t = thirds row) or, with minimal movement of the index finger, r3 r2 t3 r4 / r2 t4 t2 r3.

Minor scales

A recommended fingering for harmonic minor:

Melodic minor (different ascending and descending):

src: guerrerastyle.com

Register switches

Larger and more expensive accordions may have as many as seven register switches on the bass side, controlling which reed ranks play and thus the octaves and voicing of the bass notes and chords, similar in concept to the treble register switches on the keyboard side. Smaller or simpler accordions may have no bass switches, or a single switch that toggles between two settings.

With the soprano or alto register selected, bass buttons exactly duplicate individual notes from the chords, without the usual added lower (tenor and bass) octaves.

An accordion with one or two register switches on the bass side might provide tenor and master registers, while accordions with additional switches might have larger subsets.

src: www.miglioribrokersopzionibinarie.it

Common configurations

src: pbs.twimg.com

See also

• Array system, same circle of fifths system for an mbira
• Alternate bass
• Free-bass system

src: pmatu.files.wordpress.com

Notes

src: www.miglioribrokersopzionibinarie.it

References

Source of the article : Wikipedia