VIENNESE OBOE
The sound of the Viennese oboe can be heard only, when Viennese orchestras are playing - everywhere else the oboists use other instruments, especially of the type of the French oboe.
These instruments are a little longer and do not only look differently (see the graphic below), their sound is noticeably different also. We tried to localise this different in scientific terms.
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Comparison of three types of oboes. On the left an oboel of the 19th century, in the middle a French oboe and on the right the classical Viennese oboe. |
If one listens to Viennese and French oboes, one gets the impression, that the biggest difference is in the vibrato, which is used very seldom by the Viennese instrument and practically always by the others. But as the vibrato can be played on the Viennese instrument as well as on the others, it is specific to the style of playing and not to the instrument.
If one asks oboists about the difference between the instrument types, one of the first answers will usually be, that on the Viennese oboe the change between the first and the second register takes place at b2, which is three semitones lower than on the French Instrument. This means e. g., that the solo at the beginning of the Florestan aria in Beethoven's Fidelio needs a register change on the Viennese instrument, while it is played in one register on the French instrument. This difference, however, cannot be seen in the partials (in the lower part of the next figure the sounds go from front to back, the register change is in the lower picture after the first sound). This is not surprising, because one cannot hear it (at least with good instrumentalists): this solo is not meant to show a register change but to show "the heaven opening ".
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French oboe |
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Viennese oboe |
From this (and other) examples we conclude, that the register change does not contribute to the different sounds of Viennese and French oboe.
Next we tried to localise the difference with the concept of formants; again we were not successful.
We could show, however, that the decrease of the partials following the biggest partial is significantly different for the two instrument types: the decrease is slower for the Viennese instruments. This can be seen in the following figure, which shows the spectrum of the partials of the sound e1 (mezzoforte) for four Viennese (w1, w2, w4, and w5) and two French (f1 and f2) oboes.
the spectrum and the regression curve for the sound e' Mezzoforte for four Viennese (w1, w2, w4, and w5) and two French (f1 and f2) oboes
The decrease can be represented by the gradiant (k) of the regression, which is also shown in the pictures: As the slope for the French oboes is much steeper the absolute value for k (in the upper right corner) is about twice as high as for the Viennese instruments
The next figure shows the mean absolute values of k for five sounds in three degrees of loudness for Viennese and French oboes.
the mean absolute values of k for the Viennese (w) and the French (f) oboes together with the respective maximum and minimum values taken from a total of 90 sounds
From this Figure the following can be seen:
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The absolute values of k are nearly always higher for the French oboe - the slope of the curve is steeper. |
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For the French instrument the absolute value of k is always decreasing from Piano to Forte which means that the slope of the curve becomes less steep. |
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For the Viennese Oboe this slope is about the same from Piano to Forte - at least up to g''. This means that the sound colour does not change much, the sound becomes only louder. |
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Therefore the difference in timbre between the two instrument types gets smaller from Piano to Forte. |
