The Trumpets Are Closed?

Discussion in 'Trumpet Discussion' started by Bachstul, Aug 27, 2009.

  1. nordlandstrompet

    nordlandstrompet Forte User

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    At least, in this picture there is a trumpet :-P

    [​IMG]
     
  2. dhbailey

    dhbailey Piano User

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    Forgetting Jennifer Aniston (whom I've never found attractive to begin with), is that a real trumpet that plays? Those very acute angles on the leadpipe and the bell makes me wonder. Has anybody on this forum played a trumpet configured like that?
     
  3. nordlandstrompet

    nordlandstrompet Forte User

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    It is a real trumpet, and it plays.
    I played most of the maker's models, but not this model.

    You can read about it (and other models) here:
    Taylor Trumpets
     
  4. dhbailey

    dhbailey Piano User

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    New Hampshire
    Thanks for that link -- very intriguing!

    Concerning your tag line: "Wife shouts: Trumpets are expensive!" tell her to be quiet and be happy you're not a violinist, where the most expensive trumpets are less expensive than even cheap good violins. I'm lucky in that my wife is a violinist, so when my son and I start discussing new trumpets, we're talking about amounts of money which are substantially less than the amount she is considering for a new bow!
     
  5. Sofus

    Sofus Forte User

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    You don´t happen to know what
    Pamela Andersson is doing these
    days, do you?

    :-)
     
  6. nordlandstrompet

    nordlandstrompet Forte User

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    Saw her a couple of days ago, shopping for a new Taylor

    [​IMG]
     
  7. Sofus

    Sofus Forte User

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    Is that really HER, nordlands?
    I think she´s LOST IT!!:-(


    Anyway, IS the trumpet bell open or closed?

    Here´s a document that I´ve written, just for clarification:

    [​IMG]


    What do you think about this, rowuk and NickD?
    My conclusion is this: since the air impedance
    ouside the trumpet is lower than the air impedance
    inside the trumpet, the reflection coefficient is
    negative. This corresponds to a "semi-shortcut" in
    the electrical case and a "semi-open" bell in the
    trumpet case, i.e. the BLUE dot in Case C.


    I might be wrong about the inner air impedance being
    higher than the outer air impedance. The shape of the
    bell maybe is made in such a way that it takes the inner
    air impedance from being higher than the outside air impedance
    to instead being lower than this. I however doubt this very much . . .
     
    Last edited: Aug 31, 2009
    Bachstul likes this.
  8. rowuk

    rowuk Moderator Staff Member

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    Sofus,
    you are my hero! An excellent analysis! it is also about 90% true!

    Modifications: A horn is reactive in its passband so we have a different coupling/tranformation at the bell. We also must consider keeping the player alive, so we have to "leak" enough DC component (no reflection) to allow the player to breathe at sensible intervals.

    Another point that has to be calculated into the formula is the reflections that cause the partial series and that the acoustic length of the horn changes with frequency to keep the octaves in tune.

    One thing probably impossible to model would be the small inefficiencies that can be used to correct intonation problems (mass like valve caps, bracing or heavy mouthpieces).

    You are very close and this is the BEST drawing that I have seen to date. THANK YOU!
     
  9. Markie

    Markie Forte User

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    A trumpet is a closed system. Check out The University of New South Wales site on open verses closed systems.
     
  10. ComeBackKid

    ComeBackKid Fortissimo User

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    Any links available for this? Sounds interesting.
     

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