Although the requirements for church organist position may vary from church to church and from denomination to denomination, they may require you to play some or all of these things:
1. Sight-read a hymn from the hymnal. Usually the standard way of playing is enough here: soprano and alto in the right hand, tenor in the left hand and bass in the pedals. If you want, you can choose some more advanced dispositions for more variety as well.
2. Sight-read a passage of organ music. It could be written in 2 or 3 staves with or without manual changes.
3. Transpose a hymn from sight. This transposition usually is no more than major third apart.
4. Sometimes they can ask you to harmonize a hymn in four parts. Observe proper voice leading, avoid parallel fifths and octaves, and choose the chords according to the principles of functional harmony.
5. Sight-read an accompaniment part of the choral anthem on the piano or the organ. It will usually be notated on two staves.
6. Sight-read a psalm accompaniment. They provide you with the psalm book.
7. Play one or more solo organ pieces suitable for prelude, offertory, communion, postlude, weddings, and funerals. All of them can be prepared in advance.
8. In major organist positions, they may require you to improvise variations, a chorale prelude, a piece in ternary ABA form etc.
During interview part sometimes they also ask you about your personal faith, your education, and professional experience so be prepared to answer these questions.
Things to remember:
1. You will have to play a hymn as you would in the service with proper registration and with all the different verses. In some cases, you may be required to sing a hymn while playing as well.
2. They also may require you to submit a professional CV or a resume, one or two letters of recommendation, and your diploma.
3. It is better if you don't ask about the salary right away. Let them make a proposition for you.
These are the general things that you might be required to perform. If you want to know the specific requirements for your situation, just ask your prospective church officials. Remember that the more fluent you are in each category, the more successful you will be.
Treat this audition as a competition because there might be other applicants for the same position. You will have to outrank them in each category in order to be successful.
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