Sunday, February 27, 2011

Conductors' Knowledge

i solemnly swear that regular posts will begin again after march 8th (the day after my only other audition).

for now, i am concentrating on learning the Wagner Tannhauser Overture, the Sacrificial Dance from Rite of Spring, and all the material that was covered in the test last week (wow it has been a whole week since that day).

today's post includes the following material:
trombone slides
harp charts
twelve-tone rows

trombones are strange instruments. this graphic is pretty clear on what they can do.
the question that likes to come up on conductors' exams, apparently, is usually regarding their most atypical of traits, the slide. so in the above picture you can see that in any one position a trombone can only hit the notes of a harmonic series, the same as any other wind/brass instrument that couldn't change the fundamental by using keys or valves. trombones don't have valves, so the slide changes the fundamental by adjusting the length. the higher the position (in number), the lower the fundamental note of the series it can play in that position.
the lowest a trombone can play is the low E (it's an E2) in 7th position. by adjusting lips, one can obtain the higher notes in that harmonic series, in other words B2, E3, G#3. (just for the sake of clarity/thoroughness, the trombone has a range of E2 to about F5, and reads music in alto, tenor, and bass clefs. it does not usually transpose.)
slides are obtained by keeping the lips in the same embouchure but continually adjusting the slide/changing the position. the fact that the largest slide a trombone can perform is a tritone is a matter of practicality - since the first interval in the harmonic series (other than the octave) is the fifth, you only need a range of diminished fourth in the fundamental to be able to cover basically all the notes within your range. (it also happens to be just about how long people's arms are...)
i don't actually know what i would have written for the answer to the question last week if i had known all this. what i remember him asking was, are these slides possible? (and to this i just marked Y to the ones in which the range of the slide was tritone or less) and then if we could state what position the trombone had to be in to do the slides. since slides cover several positions (all of them if the interval is a tritone), i guess i would have put the starting position-ending position.

the harp:
this is basically a recap of the information i posted last week. the harp has a total of 47 strings, ranging from Cb1 to F#7. the lowest two notes, a C and D, and the F, are technically not attached to the pedals which alter the accidentals chromatically for every octave of a given note. they can, however, be pre-tuned. otherwise their usual tuning is just C1 to F7.
notes on harpists: they only use four fingers of the hand (exclude the pinky). generally one hand can have the range of a tenth. and since the right arm wraps around the instrument, it generally plays nothing lower than a G2.
the seven pedals are: D C B | E F G A.
pushing the pedals down makes them sharp; raising them makes them flat.
after you know this, the pedal diagram becomes instinctive...

twelve-tone rows:
12 tones in a sequence. these use of the tones is rather rigid: no altering the fundamental order of the row, no repeating previously stated notes (unless you are merely repeating one note over directly afterwards) unless you have gone through the rest of the row first. but there are a number of provisions which make this marginally less binding.
first, you're allowed to use repeated notes (as long as the note you are repeating has no other notes in between)
second, you don't have to use all the notes exactly in the same rigid order. for example, you might have multiple lines going, and you have to use all the notes in one bar including all the parts, before you can start repeating notes in the next bar. in other words, one voice doesn't have to hit all twelve tones.
third, and most likely to come up on an exam because of its formulaic nature, is the process of inversion and retrograde.
retrograde is the easier of the two; it's merely your twelve tone row backwards. start with the last note, end on the first note.
inversion is more or less what it sounds like. you start on the same note as the original note, but you go in all the opposite directions. so if your row has the first three notes: Eb, (downwards minor third) C, (upwards perfect fourth) F, then your inversion will have the first three notes: Eb, (upwards minor third) Gb, (downards perfect fourth) Db. your result should still be a twelve tone row. unfortunately when i did this last week i ended up with a repeat somewhere. it's easy to mess it up if you are under time pressure and don't have time to write numbers and that sort of thing. but the concept is simple.
retrograde inversion is an inverted row, backwards. i guess there could also be an inverted retrograde, but i'm not sure anyone uses it :P

coming up soon - some transposition notes, counterpoint 101, and various other notation details regarding particular instruments.

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