All of the above said, I will list the standard instrumentations for orchestras, using a generally universally accepted index.
The way the instrumentational indexing works is:
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First set of 4 numbers
Flutes-Oboes-Clarinets-Bassoons
Second set of 4 numbers
Horns-Trumpets-Trombones-Tubas
T+x
Tympani and auxiliary percussion
(i.e. number of players needed, not number of actual percussion instruments)
Hf, etc.
Harp and other misc. instruments
(i.e. Pf = piano, etc.
Strings
Assumes Violin 1, Violin 2, Viola, Cello, Bass
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Various symbols such as
* and
= before a woodwind instrument denotes an auxiliary instrument of that type is needed. For example:
- *2222 means 2 flute players with one doubling on piccolo.
- *3222 means 3 flute players with one either doubling on piccolo or playing piccolo exclusively.
- 22=32 means 3 clarinet players with one doubling on Bass Clarinet (* means Eb Clarinet) or playing Bass Clarinet exclusively.
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Standard Orchestra Sizes
Classical
2222 - 2200 - T - Strings
Romantic (Brahms)
2222 - 4230 - T - Strings
Romantic (Extended)
*3*322 - 4331 - T+2 - (Hf) - Strings
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There are of course countless variations of these, but these models are the points of departure. Late Romantic Composers such as Richard Strauss and Mahler use gigantic orchestras that do not adhere to any rules.
Strauss' popular
Don Juan is not too big, it calls for:
*3*32*3 - 4331 - T+3 - Hf - Strings
But his
Ein Heldenleben requires:
*4*4=4*4 - 8531 - T+4 - Hf - Strings
Mahler, the craziest of all the Romantics, requires the following for the
1st Symphony, which is typical of his orchestration:
*4*4=4*3 - 7431 - T+3 - Hf - Strings
His
8th Symphony, the "Symphony of a Thousand" goes like this:
*6*5=6*5 - 8871 - T+3 - Hf, Cel, Pf, Org, mandolin - Strings
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As far as a suggestion is concerned to our young composer, stick with
2222 - 2200 - T - Strings. If it was good enough for Beethoven, it probably will work fine for you.