Adjusting mouthpiece gap

Discussion in 'Trumpet Discussion' started by robeebee, Sep 14, 2013.

  1. robeebee

    robeebee Pianissimo User

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    Jul 24, 2013
    Sydney Australia
    How many of you guys have actually done this?

    I've ordered a kit to close up a large gap, which will hopefully help a little
     
  2. gmonady

    gmonady Utimate User

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    Dayton, Ohio
    I will be. The problem is... I switch mouthpieces between my Jettone and standard piece when I convert to lead, so adjusting for the gap AND being able to exchange different mouthpieces may be precluded. I bought the Harrelson Gap Solution Kit and do plan to use it once I get my Harrelson trumpet for my Jettone, as that is the only mouthpiece I plan on using for the Harrelson trumpet. I may actually use it on my Ambassodor, as I exclusively use the Olds 3 mouthpiece for that horn. The Harrelson kit will fit 5 trumpets.
     
  3. Vulgano Brother

    Vulgano Brother Moderator Staff Member

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    A gap in time saves nine.
     
  4. Dean_0

    Dean_0 Piano User

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    Jan 21, 2013
    NE
    I have a story :

    I have had a 22B for a couple months now,at first i thought it was just my lack of practice ,(some times i didn't get to play for several days) anyway i seemed to be having slotting issues with the horn ,trying to play high , ;-)Well high for me? ,,,,was very difficult ,taxing on my chops , The buzz just seemed to break away at strange times too , i just kept thinking to myself it shouldn't be this hard ? :think: in fact i was bothered by the nagging question if i had made a mistake? :noway:

    Well several weeks ago I happened to find this,,,, The Conn Loyalist ,,which got me thinking,maybe using a modern (Morse Taper) wasn't a good idea ?

    So the search began for a better fit ,,,,i found and got a CONN BI 522 that is gold ,thinking it should be old enough to have the different taper ,,,nope :dontknow: according to what i see it has a Taper very close to ,or the same as a Morse ,Back to searching :-(. So I preformed the tape Cheat and used it anyway on a Sunday Gig ,I was happier with the horn now ,but still didn't like to have to bother with tape .

    The Conn Crhonology of M/p's as i understand it?:

    2 Letter 3 number series ex. BI 522
    Precision Series ;numbers and letters run length wise on shank , no ledge below #
    Improved Precision Series :numbers and letters run around the shank ,with an ledge below

    I Wasn't sure what to look for now ,then i went back and re-read the page and discovered that the older Precision piece is what i needed ,I got it today ,and to my amazement it gives the proper gap ,About .990, Playing is much better than the first piece i used ,the horn just seems to go where i want it too without fighting me ,if that makes sense? Time will tell of course but i think i have it sorted now.

    So i guess i will check the gap on the rest of my horns ,so many of us use different M/p,s than came with our horns I'm sure it a good idea to check each Piece for fit .

    I do wonder though ? Is there a standard for what the gap should be? or is each horn going to be slightly different ? i dunno ? Now i'm sure it's worth messing with .
     
  5. stumac

    stumac Fortissimo User

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    Flinders Vic Australia
    I believe the general consensus of opinion is that the gap should be between 0.10" and 0.15", the GR website had a formula for calculating the optimum gap using the relative diameters of the exit of the mouthpiece and the entrance to the leadpipe and the wall thicknesses of each.

    My own research with a Wedge MP with a set of 5 shanks that give + and - 1/8" show this to be right. However there are exceptions, my Selmer Radial Bb seems to respond best to no gap, my Radial C does not seem to matter what the gap is.

    The need for optimising the gap only is necessary when there is a step change in diameter between the receiver and start of the leadpipe, my horns that have no step are the best responding and least mouthpiece sensitive, Benge 3x MLP and Balanced Selmer, the Selmer has a gap of 0.6" and very small step.

    To this end I have made an extended No 1 Morse taper reamer to remove the step and allow a smooth transition from the receiver to the leadpipe, I have done this to 3 horns so far, Getzen Super Delux Frankenhorn, Buffet-Crampon balanced and an I+K "C", in each case it has produced a more uniform response throughout the range and become insensitive to mouthpiece changes.

    The only downside I can see is that it has made the horn seem more free blowing, wether this is a result of removing the step or the increase in diameter at the entrance to the leadpipe or both I do not know.

    Regards, Stuart.
     
  6. Cornyandy

    Cornyandy Fortissimo User

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    East Yorkshire
    I still think the most important gap in trumpet playing is the one between the ears.
     
  7. gmonady

    gmonady Utimate User

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    Jan 28, 2011
    Dayton, Ohio
    I have a kit I can use to help you on this. Let me admit you to my Ward Service.
     
  8. Dean_0

    Dean_0 Piano User

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    Jan 21, 2013
    NE
    P.S. sorry the gap shouldn't be anywhere near .990 that is the insertion depth for the 22B ,gap should be more like what Stumac says ;-)
     
  9. robeebee

    robeebee Pianissimo User

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    Jul 24, 2013
    Sydney Australia
    Interesting

    So most of you adjust the gap

    Never was spoken of in my time

    Not that I listened to anyone
     
  10. SeanLondon

    SeanLondon New Friend

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    Aug 4, 2012

    Yes, trial and error and just getting on with it are usually the solution to most things...

    but...I've been dealing with this gap problem over the past few years. It's difficult. My experience with vintage Conns is that it's good to follow the advice on the Conn Loyalist site (basically add a little bit of tape to the shank of the mouthpiece, so it doesn't go in as far).
    I've also been experimenting with gapping and a v nice LA Olds Recording tpt.
    I agree that reduction in gap seems to make horns free-blowing and easy to play quietly and sweetly in the mid register. But I have found that on gigs and playing at volume a larger gap and more initial resistance is better for slotting and confidence in the upper register. And this set up is better for endurance, for some reason...
    I don't think I understand the physics at all... but I would certainly say that how (and where) the mouthpiece sits in the receiver really affects performance.
     

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