Forum Top Banner Ad

Collapse

Ebay Classic organs

Collapse

Announcement

Collapse
No announcement yet.

Reed Tongue Stability

Collapse
This topic is closed.
X
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Reed Tongue Stability



    Is it normal and customary for the tongue of a reed pipe to require recurving now and then over the years due to the pipe's speech and tonal characteristicssuddenly becoming unstable?




    We have had this happen at churchon the bottom octave of two different 16-foot (full length) reed stops and once on the bottom C of an 8-foot Vox Humana. The boots of the 16-foot stops are relatively small in the bottom octave--could this have anything to do with stability? (The boots of my 16 octave--half-length, by Schopps--here at home are relatively large and are very stable.)




    The rest of these ranks are very stable indeed. So, I speculate that somewhere along the way, these tongues may have been regulated for one reason or another, but perhaps not with the utmost skill. Thus, while they may have been fine for several months, it was only a matter of time before the tongue required further adjustment(?).




    We are talking about pipes that are about 35 years old and on 3-1/2 to 4 inches of wind. The temperature in the church is reasonably stable, albeit not controlled 24/7. However, the instability does not appear to be related to temperature or humidity, but appears to be quite random.




    This looks like a good question for Mr. Odell . . .




    [:^)]




  • #2
    Re: Reed Tongue Stability

    Ultimately I would have to defer to an experienced reed voicer, but let me take a stab a it:

    When doing restoration work, assuming things are in order to begin with, we often we seek to do as little recurving as possible.  It is something I leave entirely to the judgement of the voicer.  If a rank is well made,  properly prepared and voiced to begin with, there is little for us to do but repair the damage and clean it up.

    That said, it is ackowledge that over time various factors (such metal fatigue) can make some recurving necessary. Other factors that govern how a reed tongue behave over time include the hardness and thickness schedule of the brass, as well as the direction of the grain of the brass relative to the shape of the tongue. Once in a while I find reeds onsite that need a little tip curve taken out to quicken them up, but usually not the other way around.

    Be aware that over-frequent tuning can sometimes have deleterious effects, especially if the wire has too much tension on it.  As such, frequent movement of the wire can create s slight burnishing action that could, in turn, add curve where you least want it (the upper body of the reed tongue).  

    Overall tuning stability depends on good voicing practice, cleanliness and the proper relationship between resonator, socket and windchest channel. Often in an otherwise stable rank you can have one or two pipes that always need attention.  In such a situation there may be a nodal relationship between the resonator and socket, or the tongue may be ever so slightly out of place.  A good voicer/finisher knows what to look for and how to amerliorate such problems.

    Socket size is certainly an issue. In my experience, with the lower octaves, larger sockets seem to  improve stability.

    Comment


    • #3
      Re: Reed Tongue Stability



      Thank you, Edward; that is most enlightening indeed !!




      [:)] [Y]

      Comment


      • #4
        Re: Reed Tongue Stability



        Here is some follow-up information for Mr. Edward Odell:




        The pipe in question that is unstable at present is bottom "E" of a relatively small-scale 16-foot bassoon. The bottom octave is full-length, but mitered to be half-length (so to speak). I discovered that both the speech and voicing are abnormally sensitive to the most minimal adjustments to the "scroll" at the top of the resonator. Adjusting the scroll tends to change the speech attack and voicing more than the tuning.




        This strikes me as the reverse of what one should expect; unless I am the one that is backwards rather than the pipe. But I always thought that the so-called tuning wire was actually more of a voicing wire and the top of the resonator was just as much for tuning, if not more for tuning, than voicing. I somehow have fallen under the impression that most of us tend to touch up the tuning of reeds with the wire more for convenience than for literal correctness.




        I mention all of this in the hope that it may shed further light on the behavior of this pipe (rather than just deepening the mystery).




        Thanks again!




        [:S]

        Comment


        • #5
          Re: Reed Tongue Stability



          In a flue pipe, where the only moving component is the column of air, the length of the pipe is the major controlling element as far as tuning is concerned.




          In a reed pipe, the vibrating brass tongue generates the fundamental tone which is rich in harmonics. Moving the sliding wire changes the length of the vibrating part of the tongue, hence the frequency shifts. You can still get sound out of a reed pipe without the resonator, although it will sound pretty bad.




          The resonator part of the pipe is cut and shaped to accentuate one or more harmonics of the vibrating reed. This "forms"the specific tone that identifies the pipe as an oboe, bassoon, etc. You can tune the resonator to the fundamental or any harmonic of the tone, which will thus change the voicing. Normally the reed frequency and the resonator frequency (length)are evenly matched, but this is not so in all pipes.




          So in your above discussion, I think you have been under the wrong assumption of how the various components of a reed pipe works.




          Bob M.

          Comment


          • #6
            Re: Reed Tongue Stability



            Thank you, Bob, for clearing that up for me! So they really are "tuning wires" but can be used as "voicing wires" in conjunctionwith adjustments at the top of the resonator.




            I know that somewhere I heard the following: "Voice with the wire but tune with the resonator." In fairness to whomever said that, perhaps I took it out of the proper context? I was surprised and a bit confused when I heard it.




            I can say that with my trumpet here on my residence organ, you can go somewhat either way. Moreover, if you move either the wire or the top of the resonator too far, the voicing of the pipe changes. I am going to guess that this is because my trumpet stop has resonators that are just the right length to be in "perfect balance" with the tongue and the note that each pipe was designed to play.




            Now we have a quarter-length 16-foot Schalmei Regal at church where the resonators can actually slide just like a trombone (a real trombone, not an organ stop). Interestingly enough, sliding the resonators does very little to the voicing and not much to the tuning. I suspect that this has something to do with the resonator being so short relative to the fundamental, but let's not go down that road right now.




            So, getting back to the recalcitrant Bassoon pipe at church: The apparent hypersensitivity of the pipe to adjustments at the top of the resonator makes me think that thecurvature of the tongue is still off from its ideal condition.




            Thanks again!




            [<:o)]

            Comment


            • #7
              Re: Reed Tongue Stability

              MS, I think you're on the right track with working with the reeds. When people say "tune with the wire", I think they are assuming that the pipes are already voiced and "perfectly" regulated.

              When I work on my reeds (been doing a lot of that lately), I use both the wire and scroll for voicing and tuning. You kind of have to to find that "sweet spot".

              Did you take apart the boot of that trouble Bassoon pipe? If not, you should check and make sure the tounge isn't out of place or anything. Sometimes when the wire is moved a lot, the tounge tends to drift.

              I have a question of my own related to this. I've been trying to get my large scale Trumpet that was on 5"WP in its original installation to play on a little over 3". I know this is really really pushing it, but I've had great success with the upper 4 octaves. The 8' octave is giving me problems though. They take FOREVER (like 15 seconds!) to speak. Any ideas besides putting them on higher wind?

              Trevor


              *DISCLAIMER*: I don't really know what I'm doing so if you ruin your pipes it's not my fault!

              Comment


              • #8
                Re: Reed Tongue Stability



                An additional point - check the resonator for any leaks or cracked seams. The slightest leak will make the pipe unstable. You need to balance the wire and resonator for pitch and voice. What's the hardest to tune?IMHOprobably the Vox Humana. At least fo me!



                Comment


                • #9
                  Re: Reed Tongue Stability



                  Hi Trevor,




                  Thanks for your input! Yes, I have had the tongue out and recurved it several times. I consulted with our professional techician and he says that reed voicing is almost an alchemist's art and a profession unto itself. I have no doubts about that.




                  Al may have hit on something when he mentioned leaks. These resonators plug into a short stalk coming out of the boot. I may not have the resonator in the stalk tightly enough. Perhaps even the seams are not aligned as they would prefer to be. Also, the scroll at the top of the resonator is no longer a nice neat coil after all my messing with it in its hard-to-reach location. This may also constitute a "leak" of sorts.




                  Our concert artist for Sunday has not complained any further although I freely admitted to him that the pipe was still not perfect. I did advise him that I thought it was good enough in ensemble for any irregularities to go unnoticed.




                  We shall see . . . Thanks again guys! [D]




                  Addendum: Sorry, Trevor; I forgot your question about your 5" trumpet playing on 3". I think it is amazing that you have done as well as you have thus far. We have a 5" Menschenstimme 8' at church that we tried to play on 3-1/2". It spoke quickly enough, but the voicing just did not sound right. So, since it was on its own chest anyway, we got a small regulatorand added a Peterson tremulant, rearranged some plumbing and the stop now sounds excellent. We are now considering having our Schalmei Regal 16' revoiced because it was designedfor 4" and we are playing it at 3-1/2". It is acceptable as is; but not what it could be. I am sorry to say thatthere appears to be nofree lunch with reed voicing.




                  Since you are dealing with 12 notes herethat are giving you trouble rather than the entire rank, might you be able to raise the pressure or perhaps even have those 12pipes revoiced? Someone else on this Forum recently said something about opening the toeholes in this kind of situation. I never knew that this would work with reeds; Ithought it was moreof a flue pipe procedure.




                  Sorry I am not being much help; but I certainly wish you all the best!!




                  [Y]

                  Comment


                  • #10
                    Re: Reed Tongue Stability



                    Trevor and MS............



                    I feel your pain. I'm fighting the same problems on my organ. My trompette speaks very quickly but my other reeds are slow. I've tried everything I know to do but not much has changed. Like you say Trevor, it's not the top octaves that are causing the problem. My problems are from C3 down. I'm thinking about packing up these reeds and taking them to Eastern for revoicing.[:'(]

                    Comment


                    • #11
                      Re: Reed Tongue Stability

                      Well, shaving down the thickness of the tounge will certainly lower the pressure required, but it may be a bit dangerous as it is a one way street.

                      Comment

                      Working...
                      X