The oboe typically plays Fs in three octaves. The lower two have a variety of available fingerings, which can be a challenge for new oboists to navigate, particularly because the available fingerings change depending upon the make of the instrument.
A typical “budget” student model instrument, for example, uses the following fingerings. (For all fingerings given in this article, the one shown corresponds to the lower octave; the higher octave is achieved by adding the first [thumb] octave key.)
The “right” F is the basic choice, to be used in almost all cases where it is possible to do so, as the tone produced by this fingering tends to be the best match to the tone of the surrounding notes.
The “forked” F tends toward a sound that might be described as “muted” or sometimes even “fuzzy,” and should therefore generally be avoided where possible (unless the muted or fuzzy sound is desirable for the musical situation—I do like to use the forked F, for example, in the beginning and ending sections of the second movement of the Saint-Saëns sonata).
Young oboists in beginning band programs learn very quickly to use the forked fingering, and some, unfortunately, learn to use it exclusively, due to the predominance of “flat” key signatures like B-flat and E-flat major that provide a good compromise for most of the beginning band’s limited technical skill. The issue here is that the “right” fingering can only be used if the preceding and following notes do not use the right ring finger on its tonehole; otherwise an extra note would be audible while the finger was still in motion from F key to tonehole or vice versa. The “right” fingering is the superior choice in scalar passages in the keys of C or F major, but use of the forked fingering is a necessity when the key signature includes an E-flat.
One additional fingering option exists here, which is rarely discussed but which can be useful in rare cases.
This could be used, for example, when moving from low C to F, avoiding a C-to-E-flat-key slide in the right hand.
For a more expensive “full-conservatory” instrument, the available F fingerings are somewhat different.
The basic fingering remains the same, and an alternate “left” F key is provided. The left F key opens the same pad as the right F key, so, if the instrument is adjusted correctly, the note should be identical whichever key is used. (On a poorly-adjusted oboe, this pad might, for example, be opened to a different height by each of the keys.)
The forked fingering is simplified slightly on the full-conservatory oboe, due to the automatic “F resonance” mechanism. This mechanism opens a tonehole that is similar in size and placement to that of the E-flat key, but adjusted slightly to optimize the forked F. This should provide a forked F superior to that of the student model instrument, but will still be distinguishable from the basic fingering. In the case that this mechanism exists, the E-flat key should not be used, since in combination with the F resonance mechanism the F will be too sharp.
Now let’s examine a sample passage and determine the best fingering for each F.
The Fs in the first measure are probably best played with the “right” fingering. The first one could as easily be played with the left F, if present, but the second is best played with the right. This keeps the movement to the G in the next measure to three fingers on one hand, more reliably synchronized than a two-handed movement. Playing the first in the same way provides the advantage of consistency.
For the same reason of synchronization, the first F in the second measure should also be played with the right hand, but the second F in that measure cannot because it moves to a D-flat. Forked F is the only option for a student-model instrument, but a full-conservatory oboe presents two options: forked or left hand. A good argument can be made for the forked F here, because, again, the motion is kept to one hand, but the left F is likely to provide the advantages of better tone and/or pitch. These advantages should probably get special consideration in this passage because the preponderance of Fs will make a variation in timbre or tuning more noticeable. I suggest that the small technical disadvantage of the left F in this case will usually be outweighed by the tone and pitch issue, though an oboe with a particularly good forked F may give the oboist the luxury of preference.
The sequence D-flat, E-flat, F in the final measure virtually requires the use of the left E-flat and the forked F to avoid sliding; on a student-model instrument, the forked F with left E-flat may be appropriate. One alternative may be worth mentioning for the sake of completeness: if the passage is played slowly, the player could conceivably begin the E-flat with the left hand, then, while sustaining the note, add the right E-flat, then release the left E-flat, and finally play the F using the left hand. For most situations this complication is not likely to be worth the effort; it does also require that the oboe be adjusted well so that the E-flat pad is opened to precisely the same width by either the left or the right hand E-flat key.
Here is the passage with fingerings marked for a full-conservatory oboe. In practice it likely wouldn’t be necessary to mark all of the Rs. The forked fingering marking, which resembles a string downbow, is the one I’ve seen most commonly used. Marking the forked fingering with an “F” can lead to confusion—an F marked with an F?
And here are the markings for a student-model oboe.