1) Fingering. When you open your new organ score and want to start practicing a new composition, don't play it right away from the beginning until the end. I mean, you could play it through once just to get familiar with it but then the real practice begins.
Write in your fingering in every difficult spot of the piece. How to find out if the passage is difficult and needs fingering? You could play it once and see if you made a mistake. If you did, stop playing, go back, figure out and write in the most efficient fingering for it.
2) Pedaling. I suggest you write in pedaling on every note in the pedal line. This is very important because unlike manual playing, pedal playing usually is a completely new skill that organists must learn.
3) Notes. When you have fingering and pedaling in place, you can now start practicing it. Observe that every single note is correct. Sometimes you can hit the wrong note accidentally but in most cases, it is better to go back and play this spot with correct notes at least 3 times in a row.
4) Rhythms. In every measure, make sure that your rhythmical values are also correct. This is usually not so difficult in places with straightforward rhythms. But when you see any complications, such as syncopations, dotted notes, duplets, triplets, irregular rhythms, meter changes and so on, you have to be very careful about playing with correct rhythms. It is best that you subdivide the beats of each measure and count out loud while playing.
5) Articulation. Do not play every note legato. For people who come to the organ from piano playing, this is especially difficult to understand at first. You see, you have to look at the historical period that this piece was created in. If you are playing a piece by a composer from Renaissance, Baroque or Classical period, play with gently detached articulation (articulate legato) unless it is indicated otherwise by the composer.
If the piece is from the Romantic or modern period, usually composers indicate articulation very precisely. So pay close attention to each slur, dot or dash under or above the notes and try to execute them in the exact way.
6) Phrasing. If you want your organ performance to become natural, try to incorporate phrasing in your playing. This helps to achieve a feeling that you breathe together with music. In fact, you should breathe slowly, deeply and consciously while playing. Look for cadences in your music which reveal perfect places for phrasing.
7) Tempo. While performing, choose a concert tempo very carefully. Evaluate the mechanics and the size of the organ. In addition, assess the room in which you play and the reverberation of the space. While practicing, usually take a much slower tempo which will allow you to avoid mistakes in your playing.
8) Practice. When you practice your piece, be very systematic about how you learn new music. It is best to practice in short fragments of about 4 measures each and later combine them together. Also for polyphonic music try to master each voice separately, then combinations of 2 voices, 3 voices and only then - the entire 4 part texture.
Strengthen the quality of your organ playing by concentrating on the above details and making the details concentrated. This approach will help you to achieve the level of exceptionally outstanding performance.
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