1. Trompette 8'. This stop is essential for playing with loud registrations in the Romantic music. It blends nicely with the overall sound of the organ. However, you can easily use it in chorale preludes or fantasias where the chorale tune is placed in the tenor or the soprano voices. The accompanying voices in another hand sound well on the 8' Principal (sometimes with the addition of 4' Octave).
Some Trompettes fit very well for playing short fugues also (North German or French Classic style). Also Trompettes are included in French Classical Grand Jeux registration.
2. Trompette 16'. In addition to being a stop for Fortissimo places in the Romantic and modern music, this stop can be used for the bass part in some chorale settings where it is played by the left hand only.
3. Clairon 4'. This stop seems best to be used in French music with Grand Jeux registration or in French Symphonic music where Tutti registration is required.
4. Vox humana 8'. It could be used in chorale settings for the chorale part or in some chorale preludes with imitative polyphony for all 4 voices (perhaps with the addition of Octave 4').
5. Voix humaine 8'. Not to be confused with its previous German counterpart. It is best used where Dialogues sur le Voix humaine registration is needed.
5. Oboe 8'. It works really well for both Baroque and Romantic music for solo melodies. On most modern organs you may need to add 8' flute to the sound.
6. Fagott 16'. This stop works well for the bass part in the continuo playing as well for playing duetts. In this case, the right hand part can be played with Vox humana or Cornet.
7. Krummhorn 8'. It works nicely for Renaissance dances and solo melodies in chorale preludes.
Try to find suitable pieces for reed stops and experiment with them on your organ. The above tips will help to make your paying much more colorful. However, as with all things, always use your ear and sense of good taste in order to show off the most beautiful reed stops on your instrument.
Finally, the use of reeds also depend greatly on the historical period and national style of organ composition you are playing so you also have to study the history of the organ, its construction and design and use the above points only as a starting point for your discoveries.
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