Leadpipe Questions

Discussion in 'Horns' started by Cornet1, Jun 3, 2005.

  1. Cornet1

    Cornet1 Pianissimo User

    232
    2
    May 22, 2005
    Essex, England
    I wonder if someone can help with a few of my queries about leadpipes,.....

    1) From reading the posts here is seems that with the 'reversed leadpipe' modfication the idea is to keep the 'interruption' of the end of the tuning slide as far away from the leadpipe as possible,....However, this 'interruption' is only the increase in diameter of the wall thickness of the tube....and, the reversed layout only defers this increase of Dia. for another couple of inches or so.

    In view of the above rather crude analysis, is it not miore likely that the real value of 'reversed leadpipe' is to increase the length of taper for another 2-3 inches?

    2) Is it true to assume that the 'common' leadpipe on mass production trumpets is a straight sided taper,....a simple 'cone' which goes from diameter of mpc end to main bore size of trumpet?

    3) In the after market leadpipes such as 'Blackburn', what are the results of different 'shapes' and which of these shapes gives what playing characteristics? Are the shapes all just straight sided tapers but different only in length? Are there any websites which show this?

    4) considering the ferrule, or receiver as its known in USA,......all of the trumpets which I have examined have a distinct start to the leadpipe which can be detected by a probe inserted into the ferrule,......However, the 9 cornets which I have examined tonight all have a continuous shaping from ferrule to leadpipe with no discernible edge to the pipe,......Could this be the reason that the 'Gap' is not important on cornets but is vital for trumpet players?

    5) On instruments with 'sleeved' leadpipes, how is the pipe retained securely and without vibration in the sleeve?

    Sorry for long and difficult post,...any help with these questions would be very much appreciated.......regards, Bob
     
  2. Tootsall

    Tootsall Fortissimo User

    4,529
    8
    Oct 25, 2003
    Yee HAW!
    Not at all: it's a great set of questions, Bob. I'll take a whack at some of them but mind you, I'm speaking from the point of view of a non-professional who has merely spent a lot of time picking the brains of those who've already chosen to share some of their info. Doubtless there will be some errors and I know right off that I certainly don't know the answers to all of your questions.

    1) Yes, the value is to add length to that which can be tapered and Yes, it moves a discontinuity which can not be otherwise eliminated slightly further down the "pipe" (and thus away from a greater number of critical nodes). You've already realized that whenever you have a slide fit you inevitably have a cylindrical section. Schilke DO manage to include taper (both increasing and decreasing) through the tubing including the tuning bow. Still, if you read what Eclipse does, their design eliminates the tuning slide and it's discontinuities entirely from between the venturi (the end of the leadpipe within the receiver (otherwise known as the smallest diameter location within the horn itself, mouthpiece not included)) and the 3rd valve. (The tuning slide being relocated to the bell bow where the effect is less with the notes have already been "formed"). Eclipse tuning bows (bell bow) have quite a noticeably taper to them with entirely different diameters at the two ends.

    2) No idea. I would suspect you are right but........

    3) Again, I'd refer to the Schilke site where they speak (or maybe they've taken that section down? or maybe it's on the Schilkeloyalist website) of both increasing and decreasing the diameter (if ever so slightly) to "adjust" the position of the nodes for each note. They must be doing something right, their large horns are notoriously accurate for the most part.

    4) In fact, "gap" is non-existent on those cornets (and flugelhorns!). I've a Getzen 800 cornet and.... no gap. Jupiter 846L (modeled on a Yamaha 631 flugel), no gap. I suspect that's why the mouthpiece backbore and taper length for cornets and flugels can be so critical to get the right "match" with the horn itself.

    5) No idea... possibly the tubes are tightly swaged together or maybe it's a shrink fit? Anybody with a TT or Harrelson?
     
  3. dcstep

    dcstep Mezzo Piano User

    684
    3
    Nov 27, 2003
    Denver
    5) I don't make Concept TT leadpipes and I've unable to find any specifics about the Twin Tube leadpipe construction. Tanabe uses a variation of leadpipe "sheathing" and he told me that he thought the main benefit was added mass. If that's the case, then they could tack it all along the leadpipe.

    I suspect, but that the Twin Tube has two or three benefits: one is the added mass, two is added stiffness allowing such things as eliminating the brace between the 2d valve and the leadpipe and three it isolates the main leadpipe/bell. On the Concept TT I think that the external tube is attached firmly at the receiver end and the main slide end of the pipe. Since the leadpipe is already a pretty sturdy piece in and of itself, doubling the tubing adds considerably to mass, stiffness and isolation from the bell. (Just my guess based on many hours looking at my own TT)

    Dave
     
  4. Tootsall

    Tootsall Fortissimo User

    4,529
    8
    Oct 25, 2003
    Yee HAW!
    Dave, is the TT concept having an air gap between the two tubes? Or do you think they are soldered together as "one piece"? (and if so... why not just make it out of a thicker tube of brass? or is it more difficult to get the exact ID shape if the brass is too thick?)
     
  5. dcstep

    dcstep Mezzo Piano User

    684
    3
    Nov 27, 2003
    Denver
    I think they're separate, but I'm not certain. The outside tube is constant diameter and the inside tube is tapered, I can see that. Selmer describes it as an inner and outer tube, but they don't get any more specific than that. When you plink it with your finger there's no added ring, but if the outer metal is as thick as the leadpipe itself, then you wouldn't expect extra ringing. I'm reluctant to cut it with a hacksaw. :oops:

    Dave
     
  6. Tootsall

    Tootsall Fortissimo User

    4,529
    8
    Oct 25, 2003
    Yee HAW!
    Maybe there's a unique resonance that sets up in the air gap between the two tubes? (provided there IS an air gap of course). Very strange... would like to see one of those beasts.
     
  7. HenriS

    HenriS New Friend

    5
    0
    Jul 11, 2005
    Maybe a silly question, but does the Concept TT accept standard mouthpieces, or do they need to have a different length or diameter?
     
  8. dcstep

    dcstep Mezzo Piano User

    684
    3
    Nov 27, 2003
    Denver
    The same. The inside of the receiver is like any other modern trumpet. The difference is all on the outside of the leadpipe.

    Dave
     
  9. bigaggietrumpet

    bigaggietrumpet Mezzo Forte User

    801
    1
    Jan 23, 2004
    Nazareth, PA
    And man those TT's are wide open...

    Perchance he's referring to a system like Smith-Watkins or Edwards, where the leadpipe is actually a sleeve that fits into a tube on the horn. On the mouthpiece receiver end, there is an eye for a screw, I believe, and that's how those are fastened down. Can't really tell the difference between a solid pipe and the sleeved version (or at least I couldn't when i played an Edwards and a Getzen side by side).
     
  10. Cornet1

    Cornet1 Pianissimo User

    232
    2
    May 22, 2005
    Essex, England
    Thank you to all respoders...this is a very interesting subject to me and is filling in some gaps in my knowledge!

    A couple of months back there was a post, either here or on 'TH' site concerning an impromtu tool to measure the inside dimensions of leadpipes...it may have been a DIY attachment for a set of internal micrometers but I'm not sure. I have tried to search but not been successful....can anyone point me to the right place please?
     

Share This Page