Questions, questions, and more questions

Over the past week, my new knowledge of these instruments has finally caught up to me.  Last night, I suddenly had a lot of questions about how everything I've learned fits together, as well as how the different instruments function.  I can never remember the word that describes that concept (the function of an instrument and the process of playing it.)  But I would really like for these questions to be answered by the end of the year, so I need to start seeking answers soon.  Here they are:

1. A general assumption I've developed based on experience with clarinet and other instruments: the more "instrument" a note uses (the farther the air travels through it), the richer and more stable it sounds.  Evidence from experience is as follows:

• Third-space Bb vs. B on the clarinet.  The Bb doesn't use a lot of the instrument and is really airy and hard to tune, whereas the B is a rich note that ideal for tuning because it uses a lot of the instrument.
• Third-space C and C# on saxophone are unstable are really out of tune if you're careful. [Diagram coming soon]



Click to zoom

• Db on flute (in or above the staff) is relatively airy and extremely out of tune [Diagram coming soon]

So, based on this logic, why is...

• F# stable on the saxophone?  In fact, it's considered one of the most stable tuning notes on the instrument, considering it's only halfway down the instrument. [Diagram coming soon]
• G#/C# unstable on clarinet if it uses roughly half the instrument?

Click to zoom

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2. What makes notes suddenly really hard to play on brass instruments?  (One note will be easy, then the next note will be really hard.)  Examples are as follows:

• F to G to A (in the staff) on French horn
• E to F (first line and space, respectively) on trumpet
• I understand why F to G is a reach.  A "partial" seems to last C - F# on trumpet. You have to completely change your embouchure on G. Is this true?

I already know that...

• Going over the break is hard on clarinet because you're going from using hardly any instrument to all of it.
• Eb to E on flute is hard because you start putting your pointer finger down and have to change your air and embouchure.
• So why do you have to change your embouchure again for the high Bb, B, and C above the staff?

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3.  What are the partials on French horn?

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4. Is there a relationship between the fingerings on either side of the French horn (F and Bb)?
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5. The tuba has a pedal tone pitched in Bb but plays in C. Why?
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6.  What are the pedal tones for the different instruments?
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7. Why is it easy to play really quietly on the clarinet and hard on the saxophone?
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8. Why is learning these instruments so easy for me? (A leftover question from last week that I forgot to ask during my French horn lesson.)
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9. Today I discovered that, if you put together half a Bb clarinet and half an A clarinet, the resulting pitch splits the pitch difference in half. So, if I played a written B (concert A for Bb clarinet and concert G# for A clarinet), the resulting pitch would be concert G# 30 cents sharp, or "concert G# and a half!" However, this still applies to notes that don't use very much of the instrument, like open G. Why does it apply when the bottom half of the clarinet was in A? Wouldn't notes get progressively out of tune as they use more instrument?