An efficient shifting technique is vital for a fluid playing style and will increase your ability to play expressively.
Definitions
Technical shifts are shifts that we make for technical reasons - moving to another position on the instrument because the passage we are playing takes us there. In technical shifts we avoid drawing attention to the shift and minimize shifting noise. As a general rule technical shifts use old finger - old bow shifts.
Expressive shifts are shifts that do draw attention to themselves and where we highlight the slide of the finger. These shifts are often new finger - new bow shifts.
Positions
A position is a place on the fingerboard where all fingers fall without changing the hand frame. When we shift, we generally shift to the whole-hand frame (where all fingers that are required on arrival are ready without any further shifting).
Our current terminology for positions is imperfect. Any note could be considered to be in more than one position depending on the context. For example, 1st finger E on the D-string could be in 1st position but could also be an extension up from half position or an extension back from 2nd position. While we need to know the common terms of 1st, 2nd and 3rd position, it is useful to practise exercises (such as Gerles finger independence exercises) that move up and down the strings in semitones. For instance we can start an exercise on Ab and then work on it again starting on A, then Bb and so on. Gerles fingerboard grid is more logical than our current terminology of positions and using it can help develop our knowledge of fingerboard geography. See Resources Bibliography for The Art of Practising the Violin by Gerle
Guide Fingers
Guide fingers are the fingers that we travel on to go from one position to the next. We can practice sounding out the intermediate notes played by guide fingers even though they are not part of the written music.
Basic shifting actions
1st to 4th position
When we shift in the lower positions (between 1st, 2nd, 3rd and 4th positions) the movement is like a piston action (similar to a trombone slide), as it is a simple forward and back movement of the arm along the violin neck. The upper arm comes towards the body when shifting up and the forearm moves directly back towards the scroll when shifting down. This is the basic shifting action in lower positions and it needs to be secure before we add subsidiary actions, such as independent movements of the thumb.
The only reason that we do not use this 'piston action' for all shifting is that the body of the violin gets in the way in higher positions. See Basic Actions with Broomstick
4th position to higher positions
Since the body of the violin (and especially the viola unless you are using a cut-away model) gets in the way when shifting up to higher positions, we need to swing the whole arm to the right and up towards the body. Lead with the elbow to swing the arm taking the hand and fingers up to the new position. The thumb however stays at the throat of the violin and swings under the neck.
It is important when shifting down again that the arm swings back to the left. The ability to pivot on the thumb at the throat helps here.
Just as in arm steering across the strings, the arm needs to be free enough so that it is available to move to a new position whenever required. If the action is not fluid it could be that there are issues with the violin/viola hold and that a fear of the instrument slipping inhibits the arm swinging when needed. See Introduction to High-Position Shifting and Holding the Violin.
Violin hold
Having a balanced violin hold during a shift is necessary to allow a fluid shifting action. Developing a balanced hold can take a long time and players often revisit this issue throughout their training. A balanced violin hold gives you the confidence to release and not grip too hard. Additional support for the violin can help (like trainer wheels on a bicycle). Place the violin scroll against a cloth on the wall or on top of a ledge like a bookshelf to encourage freedom to shift without anxiety about dropping the violin.
Know where you are going
To develop security in each individual position we first need to clearly know to where we are going! It is hard to jump over the stream if we do not know what is on the other side, whether we will be landing on mud or gravel.
There is a range of technical repertoire to develop a secure hand frame in each position and a secure knowledge of each position. At an early level we can play simple melodies such as Mary had a little lamb in various parts of the fingerboard, for instance starting on the A on the E-string then repeat starting on A on the A-string and so on.
Etudes by Schradieck, Kinsey, Whistler, Wohlfahrt and Galamians Scales in one position are particularly useful as they help develop a secure sense of each position. Double stops can also help as they build stability in the hand position across the strings. See Scales & Arpeggios Scales in One Position.
Commit to the note
After the shift the finger must commit to its note. If our fingers flap around on arrival looking for the note it will interfere not only with intonation but train a faulty finger action within the shift.
Aural map
We need a reliable aural map to guide our fingers to their destination. If we cannot hear where we are going to then we will not be able to successfully direct our arms and fingers there. It is important that aural training includes the ability to hear and sing the intervals between notes rather than just individual notes in isolation. See Shifting - Developing the Aural Map
Physical map
We need to have a good map of how to get to each new position and what is required once we are there. That is, we need to develop a secure stable hand frame in each position and fluid shifting movements to navigate between these positions. Both skills ought to be developed from an early stage of playing.
To develop a free shifting action there are a whole range of exercises from pedagogues like Paul Rolland and Sheila Nelson that give a broad understanding of the whole fingerboard from the early stages of playing. See Pre-Shifting for Sirens and Matching Harmonics exercises to develop freedom of movement, including shifting up to the highest positions.
Rely on the feel
The feel of the violin helps us shift. For example, there is a feeling of security in shifting to 4th position when the palm of the hand confidently knocks against the body of the violin.
At a more advanced level we sometimes need to rely mainly on the physical feel.
When the tempo is fast and we do not have time to individually hear each note. We may hear the whole group or patterns of notes and rely on our fingers to successfully fill in the individual components.
When the texture of the music is so dense or the music so complex that it makes it hard to hear our note. In these cases we can rely on guides such as harmonics (especially the one half way along the string) or the feel of a note on a lower string (for instance when playing the 5th, 6th, 7th and 8ve above the 1st finger on the string below).
The bow
A freely moving bow can help the left hand stay calm during a shift. Therefore use enough bow when shifting so that the sense of release in the right hand helps the freedom in your left hand and arm. If your bow arm feels constrained because you are running out of bow it inhibits your ease in shifting. In general the speed of bow should match the speed of the shift.
Guide fingers
Guide fingers, which play intermediate notes, are used in all shifts including double-stops, except when we use new-finger expressive shifts. These guide fingers can be played in the key or just follow the physical distance required. It is useful to practise both ways.
General principles
To shift up from a lower finger to a higher finger, travel on the old finger
To shift up from a higher finger to a lower one, begin to travel on the new finger. In performance you usually exchange fingers during the shift.
To shift down from a higher finger to a lower one, travel on the old finger
To shift down from a lower finger to a higher finger you begin to travel on the old finger. In performance you usually exchange fingers during the shift.
Some pedagogues, such as Flesch, believe that guide fingers are strictly for practice only and should not be used in performance. However when playing with portamento, or using the shift for expressive effect, we can sound them out for at lease part of the shift. See Guide Fingers and Shifting in Double Stops
For a detailed table of shifts see Gerles Art of Practising the Violin and Lucktenbergs Joy of Shifting.
Tempo
The speed of a shift is important in deciding not only what fingering to use but also how much pressure needs to be released. When playing technical shifts, the longer we have to get from one note to another, the slower we make the shift and the more we release both finger pressure and at times bow pressure to make the shift less audible.
In general we aim to play a shift as slowly as the music will bear, since the slower it is, the more secure it is. Generally a large shift will start fast and slow down near its arrival point.
Momentum
Often we need to just direct one part of the body to move and then use momentum appropriate to the distance and style of shift. For example, a shift from 1st to 3rd positions in a Classical piece at a soft dynamic will use differing actions and degree of momentum compared with a loud Romantic shift from 1st to 8th position.
A small preparatory movement of the elbow in the direction opposite to the shift (like a small back swing) can help release any tightness in the arm. This can also help give strong momentum for a fast long shift.
Release of finger pressure
If the finger or the thumb is pressing into the fingerboard or neck of the violin while shifting then we are shifting with the brakes on. This will cause a jerky, hard-to-control shift. Practising with harmonic touch or with the thumb underneath the neck in the lower positions can help teach the hand to release when shifting. See Release Pressure
While the finger action is generally light during a shift, the fingerfall on arrival needs to be clear and precise and commit to the note. Practise repeated tapping of the arrival finger to improve the security of intonation.
The degree of release of finger pressure depends on context and tempo. A faster shift gives less time to release and reapply finger pressure, and since the shift is fast there is less need to minimize the audible slide. For expressive shifts and a range of portamentos and glissandos the finger needs to be in the string enough to create the effect. For chromatic glissando the finger needs to be firmly in the string.
Descending shifts
Descending shifts are challenging because the violin hold feels less secure while shifting the left hand away from the body. As we shift down we also are shifting away from the extra contact between the hand and the violin that we have in higher positions.
To maintain freedom in descending shifts:
Check you have a balanced violin/viola hold (especially one where the scroll of the instrument does not droop).
Make sure that the hand returns to its optimal shape (forearm in line with hand, double contact if needed) when leave the body of the instrument and shift to lower positions.
Make sure that the thumb is working appropriately. See Role of thumb below.
In slow descending shifts we can contract the hand. For example in a descending shift from 1st finger back to 3rd finger, the 3rd finger can move closer to the 1st finger (causing the 1st finger to flatten its angle) in order to reduce the distance that it has to shift. See Thumb as Pivot; Stretches & Contractions
Role of left thumb while shifting
There is a difference in the role of the thumb depending on whether you are playing with a shoulder rest or without.
When playing with a shoulder rest the thumb generally shifts with the hand when shifting upwards from 1st position up to 4th position. That is, it releases pressure with the finger and glides along the side of the neck with the hand. If the thumb lags behind the hand when shifting up, it usually means that it has not released enough.
When shifting down, for example from 3rd position to 1st position, the thumb may anticipate the shift and move first but this also depends on the speed of the shift. The faster the shift the less time there is for any anticipatory movement.
When shifting from higher positions down to lower positions (for instance 5th position to 3rd position) the thumb stays at the neck to act as a pivot until the hand has moved into position before following down. See Thumb as Pivot; Stretches & Contractions
When playing without a shoulder rest the thumb is more active and if needed it can anticipate the fingers and hand and also act as a pivot for shifting both up and down. See Violin Left Hand, vol.1 for discussion on playing with and without a shoulder rest - Why Use a Shoulder Rest? and Shifting Without a Shoulder Rest
Shifting in very high positions
When we shift up very high (beyond 7th position) the hand extending from the wrist becomes the dominant shifting action and the arm position changes only a little. We may need to release the thumb anchor at the throat of the neck. In this case we can let the thumb rest on the side of the violin or on the right hand edge of the fingerboard. Players with smaller hands need to do this more often than those with larger hands. When descending the thumb leads the hand back to the violin neck.
Fingering
Think about the size of your hand. Smaller hands may need to shift more often; larger hands can extend more and shift less.
Here are some general principles for fingering, especially for technical shifts in passagework where the emphasis is on clarity rather than expressive nuance.
Shift on the beat.
Shift on a semitone.
Shift where there is a rest (or an implied rest such as on the dot of a dotted note).
Shift with the new slur.
Of course these are sometimes incompatible with each other and then you need to choose which works best.
At times we use stretch shifting to take us into the new position. In a stretch shift the finger leads and the hand and thumb follow. This is unlike a normal shift where finger and hand move together. Stretch shifts also differ from normal finger extensions (where a finger leaves the normal hand position but the hand remains in place). See Thumb as Pivot; Stretches & Contractions
See Gerles Art of Practising the Violin and Yampolsky's Principles of Violin Fingering for detailed analysis of fingering.
Shifting material
There is a vast array of shifting material including studies and scale systems by Sevcik, Flesch, Yost and Galamian. It is important to try to find even more varied material such as Lucktenbergs Joy of Shifting and Geringas 30 Studies. You can also use Starkers Organised Method of String Playing for cello, which has beautiful melodic shifting exercises that can be transposed to the violin.
SEE
Pre-Shifting
Basic Actions with Broomstick
Release Pressure
Developing the Aural Map
Guide Fingers
Holding the Violin
Introduction to High-Position Shifting
Thumb as Pivot; Stretches & Contractions
Why Use a Shoulder Rest?
Shifting Without a Shoulder Rest
Scales & Arpeggios Scales in One Position
Chords & Double-Stops Shifting in Double Stops
Resources - Bibliography and Repertoire
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