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Increasing Soundwave strength w/o affecting its characteristics?

  1. Aug 17, 2013 #1
    First please forgive my general lack of intelligence of this matter. I am a saxophone player looking to help new sax players and need some expertise for a training aid I'd like to create.

    On a saxophone, a player blows air through a mouthpiece creating a sound wave. The very tip of the mouthpiece that we blow through has a section called a Baffle which changes the properties of the soundwave to create varying sounds/styles (i.e. jazzy, funky, classical) - as such, there are many mouthpieces available that all sound different based upon their overall shape and the design of the baffle. That said, while the baffle controls the 'style', how much air we can blow through that tip also greatly affects the overall sound quality so finding a way to increase that airflow artificially without affecting its other properties (the style) is the goal.

    Essentially I want to build in a mini-propeller fan to the base of the mouthpiece (farthest from the tip) that takes the soundwave/style generated from the tip/baffle section and accelerates that airflow but without CHANGING that wave pattern/style, just strengthening it. As a result, a beginner who cannot blow a lot of air through the horn can still generate a great strong sound.

    While it would be relatively easy to put a mini fan/blower in the mouthpiece or neck to artificially increase the airflow, the key is doing it in a way that the air accelerator makes the existing soundwave 'bigger' but not 'different' - so if the player uses a mouthpiece with a special baffle to make a jazzier soundwave in general, that jazzier style still comes through unaffected, just stronger/louder as if they blew it with bigger lungs from the start.

    If the airflow accelerator (mini-fan etc) was somehow placed BEFORE the baffle, then it would work easily however the design of the saxophone mouthpiece is opposite where this airflow accelerator would have to be AFTER the baffle and therefore creates this dilemma. Any thoughts from experts would be welcome. Thanks for your time and effort and best regards, Ben
     
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  3. Aug 17, 2013 #2

    Vanadium 50

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    What you need is a fan that doesn't change the airflow on the inflow side but does on the exhaust side. I doubt this is possible.
     
  4. Aug 17, 2013 #3

    SteamKing

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    What about an amplifier?
     
  5. Aug 17, 2013 #4

    AlephZero

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    I think you are trying to solve the wrong problem here. The amount of air flowing "through" the instrument doesn't create any sound, it is just wasted energy. What matters is getting the reed to vibrate as much as possible, and then not losing the pressure changes in those vibrations.

    I think the main "engineering technology" issues are getting a reed which is properly matched in shape and stiffness ("strength") to the particular mouthpiece, and reducing sound energy losses through from poor mechanical design, e.g. air leaks and poor surface finish (inside the instrument, not outside!).

    Experimenting with different makes of reeds would be "relatively" cheap, but the design issues for the rest of the instrument mostly come down to the price of the instrument - you get what you pay for. (But attention to details like proper cleaning is important, of course).

    There could be some efficiency improvements from new synthetic reed materials, but doing your own research on that might be difficult.

    There other important factor is playing technique. If your embouchure is damping the reed vibrations, you have to blow harder to overcome that problem!
     
  6. Aug 17, 2013 #5

    sophiecentaur

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    I agree with AZ, here. The sound of an instrument depends upon the characteristics of the vibrating element (reed, lips, string etc. You would need to make the reed vibrate more and that would mean having a different gap for it to vibrate in. It would cane your lips, for a start!! Changing anything major about the way the reed vibrates would change the sound of the instrument pretty drastically.
    Most musical instrument design involves 'matching' the vibrations in the vibrating mechanism to the air and this is done by shaping the end of the pipe with a tapered bell or by using a sounding board. The 'best' instruments do this well and there isn't a lot of room for improvement, I think.
    I think you are stuck with needing an amplifier. No shame in that. Electric guitars are perfectly respectable instruments and you can hardly hear them at all without the amp.
     
  7. Aug 17, 2013 #6

    SteamKing

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    Turbo-Sax.
     
  8. Aug 18, 2013 #7

    Bobbywhy

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    If you put a fan anywhere in the air stream it's rotating blades would "modulate" the passing sound waves. It would sound like a kind of "tremolo" effect, and I doubt you'd like that result. In underwater acoustics, this same effect occurs when a sonar ping is reflected off the rotating screw of a submarine, for example. The effect is called "turbine modulation". It causes reflected frequencies to be shifted both up and down.

    Also, with a fan, how would you control it: make it run faster for a loud note, and slower for a lesser note?

    To "make the sound bigger" an electronic amplifier seems most reasonable.
     
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