1. Repeated notes. One of the most important elements in the performance of the Romantic organ music is the issue of the repeated notes. Whenever you see the repeated notes in this composition, you have to shorten them by the unit value.
For example, if the most common rhythmic value (the unit value) in the last movement is an eight note, try to shorten the repeated notes exactly by an eighth note. If the eighth notes are repeated, it is best to shorten them by half and playing a sixteenth note with a sixteenth note rest.
2. Registration. Mendelssohn wrote in the preface of his 6 sonatas that for him fortissimo means a full organ, pianissimo - soft 8' stop alone, forte - great organ without some of the loudest stops, piano - several soft 8' stops combined and so forth. In the pedal you should always use 16' and 8' stops together unless indicated otherwise.
3. Tempo in the toccata (the last variation of movement I). Although many organists love to play this toccata very fast, I recommend avoiding extremes in tempo. This is because in such a tempo you will lose the important details in articulation, phrasing and so on.
When you practice this toccata, take a slow and comfortable tempo which would allow you to avoid mistakes. If you make a mistake, go back a few measures and play that episode several times in a row correctly.
4. Practice in fragments, in separate parts and in combinations. For best results, I recommend you practice in shorter fragments of about 4 measures each. Then you will be able to correct your mistakes very quickly. As you start making progress in your playing, you can make the fragments longer.
It is also a good idea not to play both hands and feet together right from the beginning. Instead, practice right hand alone, left hand alone, and pedals alone. Then take both hands together, right hand and pedals, and left hand and pedals. Only then master all parts together.
5. Practice on the piano. Since the basis of the Romantic legato organ technique is based on the piano technique, you will improve your keyboard technique by practicing this composition on the piano extensively.
If you want, you can play the pedals on the floor while sitting on the higher chair. However, be very careful not to play this piece on the piano using the piano touch with intense dynamics and lifting your fingers high up in the air.
Instead, play everything mezzo piano with an even sound and try to keep your fingers in contact with the keys at all times. Playing this way will ensure you will get the most benefit out of the piano practice.
Use these tips as you practice the Sonata No. 6 in D Minor, Op. 65 by Mendelssohn on the organ today. If you are precise and consistent in your practice, in time you will learn to play it well.
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