Rubato

[Mandryka]

When musicians are performing, how do they decide how much rubato to use?

[jochanaan]

That's a combination of historical knowledge and "performer's instinct."  Most musicians use less flexibility in Mozart (apart from cadenzas in concertos) than they do in Wagner, because we know that Wagner insisted (at great length in his writings!) on great flexibility when he led his own music, while Mozart was rather about tasteful flexibility. (His line is "My left hand keeps strict time while my right doesn't.") In orchestral music, much of that sort of thing is worked out in rehearsals, but the precise degree of slowdown, speedup, breath pauses, and so on often gets decided on during performance, in the white-hot moment.

Actually, rubato means literally "robbed;" the connotation is that the music is "robbed" of its strictness.  I have come to dislike that term because it seems to imply that we take something away from music rather than doing something natural and inherent to it.  The term I prefer is flexibility.

[Luke]

I thought the connotation was rather that the tempo was 'robbed' in one place in order to be given to another - because rubato is not about accelerandi or ritenuti but about the discreet application of both to make the phrase breathe more fluidly but still fit against the underlying pulse (which is why Mozart's left hand v right hand dichotomy works out).

But yes, Jo's answer is the one I would give too - a mix of instinct and stylistic awareness, of pre-planning and spontaneity. There are fascinating nuggets about rubato as it was approached by e.g Mozart, Beethoven and Chopin scattered throughout Charles Rosen's books. (I'm thinking mostly The Classical Style, The Romantic Generation and Rosen's book on Beethoven's Sonatas here.)

[jochanaan]

I thought the connotation was rather that the tempo was 'robbed' in one place in order to be given to another - because rubato is not about accelerandi or ritenuti but about the discreet application of both to make the phrase breathe more fluidly but still fit against the underlying pulse (which is why Mozart's left hand v right hand dichotomy works out)....

Many musicians make that claim; yet Paderewski in this context said, "Our ethics are not so good as that.  What is robbed cannot be given back."

[amw]

Mozart was rather about tasteful flexibility. (His line is "My left hand keeps strict time while my right doesn't.")

Mozart actually wrote this out in some of his piano sonatas (written for amateurs and students) where it's very similar to what we'd now call syncopation: the right-hand notes are delayed until after the beat. This was apparently what was meant by rubato in the 18th century, not a slowing down and speeding up of tempo as modern pianists do. Tempi were flexible of course, but Beethoven (who came out of the Mozartian tradition) said that the tempo changes should always be undetectable to any but the most practiced ear. The 18th century rubato persisted until the early 20th century, mostly in the generation of pianists who were trained in the 1850s-1870s by old-fashioned teachers. (It is possible there are still some of these old-fashioned teachers around, though very few.)

The slowing down and speeding up thing didn't become mainstream until roughly the time of Brahms, though it possibly started with Schumann who will sometimes mark a passage rubato when the intended effect is actually of a slight hesitation, and whose scores contain vast numbers of tempo changes (usually ritardandi) that are intended to be brief and momentary.

[Mandryka]

I think there are four forces which contribute to rubato decisions.

1. performer's imagination
2. Score
3. performance  traditions, conservatory values
4. audience expectations

How these forces combine is the thing which interests me.

The ideas are generalisable to things like voicing, tempo, ornamentation, dynamic variation. We're dealing with something quite fundamental I think.

[Mandryka]

Schumann who will sometimes mark a passage rubato when the intended effect is actually of a slight hesitation,

How do you know that that's the sort of rubato he's after?

(I noticed this effect in Schliessman's op 17 -- more than in others.)

[Mandryka]

(His [Mozart's] line is "My left hand keeps strict time while my right doesn't.")

Is that something he said? (if so, where?) It's an idea I associate with Chopin -- I've heard people say that Chopin is close to Mozart but I've never known what they meant.

[prémont]

About Mozart and Chopin: We still do not know to what degree they used rubato.

All in all rubato is a very subjective matter. Why some performers use much rubato and others less rubato in the same music, one has to ask themselves.

I think Jochanaan nailed it in this sentence:

"That's a combination of historical knowledge and "performer's instinct." 

The expectations of the audience has hardly got any importance for serious performers of classical music.

[Mandryka]

All in all rubato is a very subjective matter. Why some performers use much rubato and others less rubato in the same music, one has to ask themselves.

Have you read Lena Jacobson's paper on Buxtehude?  (I'm unable to get it as I'm not a member of a university library any more.)

[prémont]

Have you read Lena Jacobson's paper on Buxtehude?  (I'm unable to get it as I'm not a member of a university library any more.)

No, nor am I able to get hold of it.

I have considered the possibility of contacting herself.

[jochanaan]

I think there are four forces which contribute to rubato decisions.

1. performer's imagination
2. Score
3. performance  traditions, conservatory values
4. audience expectations

How these forces combine is the thing which interests me....

There is a hierarchy here, one that I would label this way:
1. Score
2. Written sources from the composers or their contemporaries
3. Oral traditions, often passed down from teacher to student, perhaps for generations
4. Individual performers' personae and instincts

As premont says, audience expectations play a very small role, but sometimes when playing I get the sense that I need to "liven things up" if they're not paying attention, so I'll add a little more stretching or a longer fermata; I may even do that if I and the audience are communing intensely, just because I can "get away with it."  Yet sometimes, conversely, if things are going really well, I'll settle into a steady groove, not wanting to break my concentration or theirs.