Advantages of Bisonoric Instruments

Bisonoric keyboard layouts have several advantages over unisonoric layouts that may be summmarised as follows.

1. Smoother chord changes.
2. Greater control of the instrument in terms of grip and stability.
3. Fingering and keystroke alternatives on a more compact keyboard.
4. Better use of the bellows from an early stage in learning.
5. Raised awareness of musical structure and faster learning of the theory of music.

Smoother chord changes, better grip and stability

One of the advantages of bisonoric keyboard layouts over unisonoric layouts is that a bellows reversal on a bisonoric box can very often facilitate fluid chord changes, one of the most important aspects of playing any kind of music. Very often it minimises hand and finger movements, which in turn means there's no loss of stability of the instrument.

This is because very often one or even two fingers will already be positioned over the correct button just with a bellows reversal when changing chords. As one or two fingers are already positioned the fingers can stay in contact with the buttons, maintaing a light pressure, enough to maintain good control of the instrument.

On a unisonoric instrument very often in chord changes all fingers are lifted from buttons to be put down on different buttons. When all the fingers leave all the buttons the pressure holding the strap against the back of the hand is removed, which may allow the instrument to slip or wobble slightly, reducing control because there are no fingers left lightly touching a button-top to "keep position."

Fingering and keystroke alternatives on a more compact keyboard.

The beauty and great advantage of the bisonoric Atzarin layout is that it provides similar finger alternatives to those afforded by the additional rows on a chromatic button accordion. Very often repeated patterns, that is, patterns that have different notes but the same melodic intervals over the pattern can have exactly the same shape and fingering but in different directions of the bellows.

A simple example is a Major triad chord arpeggio. Whilst on a 3 row chromatic button accordion arrangement the arpeggio will have the same shape in the 8 musical keys whose tonic note is found on the first two rows, arpeggios starting from the 3rd row will have a different shape. On an Atzarin layout any Major triad chord arpeggio can have the same shape in all 12 musical keys!

This is a result of edge effects common to all small isomorphic layouts, whether unisonoric or bisonoric. That is, the regular, repeating pattern is broken at the edge of the keyboard because of alimited number of buttons. On a unisonoric system, the musician must wrap around to the other side of the keyboard to find notes, whereas a bisonoric system can bring the next note needed closer to the last note played just with a bellows reversal.

Better bellows technique and raised musical awareness from the outset

On a bisonoric instrument bellows reversals are much more closely linked to the music than on a unisonoric instrument, and are planned around, motifs and phrases or around chord changes, so bellows technique is similar to correct breathing technique when singing. In contrast, on a unisonoric instrument it is usually more of a regular pumping - 2 bars in and 2 bars out, for example, regardless of whether there is any change of chord or not. This is part of the reason why music on a unisonoric instrument often lacks the punch and bounce that the same music has on a bisonoric instrument.

This also explains why beginners on a unisonoric instrument often have such sloppy bellows work. It doesn't matter so much when you reverse the bellows, just keep monotonously pumping. On a bisonoric instrument the need to focus on the correct direction of the bellows arising from its closer relationship to the music, develops better bellows technique from an early stage.

On a bisonoric instrument bellows reversals are planned around, motifs and phrases or around chord changes. On a regular bisonoric system bellows reversals can be planned entirely around chord changes. By paying attention to bellows reversals the learner becomes aware of chord changes from the outset, in turn helping to understand the structure of the music being studied. As the student becomes aware of chord changes and chord progressions and the function of each chord in the music, the learning process is accelerated.