Assuming that you have in mind the artistic use of the pedal, I regret to say that there is no more a rule for this than for the mixing of colours upon the palette of a painter who strives for some particular shade or tint. He knows that blue and yellow make green, that red and blue make purple; but those are ground colours which he can rarely use. For the finer shades he has to experiment, to consult his eye and his judgment. The relation between the pedal and the player's ear is exactly"ALPHABETICAL_INDEX_OF" similar to that of the palette and the painter's eye. Generally speaking (from sad experience) it is far more important to know when not to use the pedal than when to use it. We must refrain from its use whenever there is the slightest danger of unintentional mingling of tones. This is best avoided by taking the pedal after striking the tone upon which it is to act, and to release it promptly and simultaneously with the striking of the next tone. It may be at once taken again, and this alternation must be kept up where there is either a change of harmony or a succession of "passing notes." This is the only positive rule I can give, but even this is often violated. Let your ear be the guardian of your right foot. Accustom your ear to harmonic and melodic clarity, and—listen closely. To teach the use of the pedal independent of the action of your own ear is impossible.
Let Your Ear Guide Your Pedalling
In Weber's "Storm" should the pedal be held down throughout the entire piece, as directed? It produces quite a discord.
Without knowing this piece, even by name, I may say that the pianos of Weber's time had a tone of such short duration and volume that the discords resulting from a continuous use of the pedal were not so noticeable, as they are now upon the modern piano with its magnificent volume and duration of tone. Hence, the pedal must now be used with the utmost caution. Generally speaking, I say—again—that the ear is the "sole" guide of the foot upon the pedal.
Use Pedal With Caution in Playing Bach
Is Bach's music ever played with the pedal?
There is no piano-music that forbids in playing the use of the pedal. Even where the texture of a piece does not require the pedal—which happens very rarely—the player might employ it as an aid where the reach of his hand proves insufficient to hold all the parts of a harmony together. With Bach the pedal is often very important; for, by judicious use—as, for instance, in the cases of organ-point—it accumulates harmonic tones, holds the fundamental tone and thus produces effects not dissimilar to the organ. Qualitatively speaking, the pedal is as necessary in Bach's music as in any other; quantitatively, I recommend the utmost caution in its use, so as not to blur the fine texture of his polyphony.
The Student with a Fondness for the Pedal
I always want to use the pedal as soon as I take a new piece, but my teacher insists that I should get a good singing tone first. Is she right?
You "want" to use the pedal? In the face of your teacher's advice to the contrary? Then why did you apply for a teacher? People who consider their own pleasure while engaged in any kind of study need no teacher. They need discipline. Learn obedience! If by following your teacher's advice you should fail to progress, even then you have no right to do anything else than go to another teacher. But he will in all probability not be very different from the first one in his precepts. Hence, I say again: You should learn obedience!