Shock Waves Propagating from bell of trumpet

Discussion in 'Trumpet Discussion' started by gordonfurr1, Feb 13, 2015.

  1. gordonfurr1

    gordonfurr1 Forte User

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    Sounding like a flute would be a very disappointing outcome.
    Sounding still mostly like a trumpet but with less energy expenditure might be nice.
    So, I am guessing having an equal number of inner and outer direction bends (if I am expressing that correctly) might be a benefit?
     
  2. rowuk

    rowuk Moderator Staff Member

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    Gordon,

    the higher the efficiency of the trumpet, the HARDER it is to play. We need the warts to even be able to play in tune. Efficiency is rated by a factor called "Q", the more resonant the horn (above a certain point), the harder it is to "overblow" it to get other partials, the more locked in the mathematical intonation is. As it is, the resonant peaks (inversely called "slots" in the trumpet world) provide the most security in the lower octaves - not only because they are further apart, but also because of the slightly higher Q. Smaller bells would decrease efficiency in the lower octave and increase it up higher.

    If you want to test high Q, get some ½" copper tubing, cut a 4 foot section, insert mouthpiece and see how "easy" it is to play, to change notes (lipslurs), to articulate. Then shorten it a bit and add a bell. Intonation gets better - still hard to play.

    Natural trumpets with hand hammered tubes have a certain amount of imperfection and respond MUCH better than instruments built with industrial drawn brass tubing. The difference is not even subtle!


     
  3. gordonfurr1

    gordonfurr1 Forte User

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    I must chew on this a bit.

    BTW, The hand-hammered Olds bell tubes, are they dimpled also on the inside?
     
  4. richtom

    richtom Forte User

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    There is really nothing new under the sun here.
    The great builders of long ago may not have had the sophisticated electronic devices to "see" what they heard, they just knew what was good and not so good.
    C.G.Conn, Mahillion, Renold Schilke, Vincent Bach, Elden Benge, and other great craftsmen experimented until they hit on the right combinations.
    Rich T.
     
  5. gordonfurr1

    gordonfurr1 Forte User

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    Well, if nothing else, I still think the photo showing the 106 db high G is very useful as it should be the death knell for using a clip-on microphone on the bell. It is exactly where the second shock wave occurs.
     
  6. Sethoflagos

    Sethoflagos Utimate User

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    Could this be a factor to explain why I find it significantly easier to develop an articulation skill (and some others) on the Wild Thing rather than the 6335H?

    I know you weren't too keen on the idea when I posted my suspicions a few months ago (http://www.trumpetmaster.com/vb/f139/really-wyrd-thing-78357.html#post778863) but a bunch of similar experiences since seem to confirm that however much good groundwork I put in with the Yamaha, I need the inefficiency of the Wild Thing to actually unlock the door and reap the benefits. Hence the rewards tend not to come to me gradually but more in the form of quantum leaps.

    If this is indeed a general truth, then it does seem to have some consequences for which are the better instruments for beginners and comebackers.


    PS Gordon: be aware that 'sound wave' and 'shock wave' are not synonymous. There can (I understand) be shock wave components in an instruments acoustic output and these will be emphasised in Schlieren imaging. But they are not representative of the majority of the acoustic output.
     
  7. rowuk

    rowuk Moderator Staff Member

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    I am not sure that efficiency and resonance are the same thing. I can envision a high "Q" instrument, but lower output due to other factors. I do not believe in acoustical amplification with a horn. There are simply less losses due to greater conformity with essential horn parameters.

    The Wild Thing that I played did not "feel" like Martin Committee soft slots. This would imply that the AC component is "realistic". The Wild Thing DID eat air however, the DC component which is not really affected by the "Q". That means I currently have no explanation for your articulation experience. I would have to make some drawings and plug in some formulas to see if I could come up with something. That won't happen soon. I have too many other things important to me that are in the way...... Sorry

    Quantum leaps are pretty small in my experience.........


     
  8. gordonfurr1

    gordonfurr1 Forte User

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    PS Gordon: be aware that 'sound wave' and 'shock wave' are not synonymous. There can (I understand) be shock wave components in an instruments acoustic output and these will be emphasised in Schlieren imaging. But they are not representative of the majority of the acoustic output.[/QUOTE]

    Yes, I understand that..and also that the shock waves are where they are, and not propagating.
    But I expect the location of a shock wave would be a terrible place for a microphone.
    Maybe another consideration that might explain Chris Botti playing at a low dynamic level and relying on the house system for amplification (and effects...reverb...).
     
  9. Sethoflagos

    Sethoflagos Utimate User

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    Pretty sure I agree with this. But there are several different ways of defining 'efficiency' and I'm not always clear which one is in play.

    Figure of speech. There was a time years ago when Arban Pg.34 Ex.32 at a quick lick was my standard warm up routine. Up until a couple of weeks ago, I couldn't get anywhere near it because I couldn't cleanly centre the interval jumps. But after switching to the WT I was getting through 8 bar sections fairly accurately within a couple of hours. Now I can negotiate the full exercise at good speed on any of my stable. And bizarrely, most securely on the Yamaha.

    In my modest book that's fairly significant. And fairly wyrd.
     
  10. jiarby

    jiarby Fortissimo User

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    106dB... What's that, mezzo piano??
     

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