Lectron wrote:I've had dreaded low C ( or corresponding low Bflat for the Eefers) on tubas with both long and short leadpipes.
Might be a coincidence, but common factors has been rather high sensitivity and efficient horns.
Also just an observation...More german/rotary than piston more conical horns
That theory sounds good on paper BUT the miraphone firebird has a longer than normal pipe AND large bore and no low C problems. The Yamaha 621 has a short leadpipe and smaller bore and no low C problems.
Okay,
This was an amazing situation. I have an old 45 S MW f tuba built in 1974. It had terrible low range, very stuffy Low C and Gb (5 valves down), etc. I remembered that Lee Stofer had changed some braces on an old horn and changed the way it played so I tried it on my F tuba- oh my goodness! The problems I had with the low register passage on the VW concerto in the first movement are much easier to play. Everything is much clearer and easier to play- good grief! This is what I did. I measured the distance between the 4th valve tubing and the outside tubing before it connects to the bottom bow, and I found that there is a "sweet spot" for a perfect placement for a brace. The temporary brace is made out of a 1/2" dia. wooden dowel rod and is pressed into place. I experimented with various placements along the outside tubing of the tuba and the tubing for the fourth valve and found the best location based on performance feedback( sound quality, ease of response)- it plays like a different tuba! If you have a newer f tuba you may not have to go thru this process, but it worked for me on my old 45 MW. Thanks Tubenet folks for enabling me to discover this.
Many wind instruments have some kind of flaring bell shape. These are generally not exponential in configuration, and are in fact used to modify the standing wave patterns of the instrument, and thereby the musical notes which can be produced.
"The flared section of the bore in many instruments are almost conical. First let's look at what this does to the spacing of the frequencies. In the page about pipes and harmonics, we saw that closed conical pipes have resonances whose frequencies are both higher and more closely spaced than those of a closed cylindrical pipe. So one can think of introducing a conical or flared section of the pipe as raising the frequencies of the standing waves, and raising the frequencies of the low pitched resonances most of all. The bell also contributes to this effect: in the rapidly flaring bell, the long waves (with the low pitches) are least able to follow the curve of the bell and so are effectively reflected earlier than are the shorter waves. (This is because their wavelengths are very much longer than the radius of curvature of the bell.) One might say therefore that the long waves 'see' an effectively shorter pipe." [1]
This has the effect of providing both the "brassy" sound of horn instruments versus woodwinds or even metal instruments which lack a flare, and also of increasing the perceived loudness of the instrument, as harmonics in the range to which the ear is most sensitive are now delivered more efficiently. However, this enhanced radiation in the higher frequencies means by definition less energy imparted to the standing waves, and thus less stable and well-defined notes in the higher registers, making the instrument more difficult to play.
joh_tuba wrote:
That theory sounds good on paper BUT the miraphone firebird has a longer than normal pipe AND large bore and no low C problems. The Yamaha 621 has a short leadpipe and smaller bore and no low C problems.
The common denominator is the small body.
I've had small bodied ones too
I have not yet gone over with a marker pen to see where the privileged meets the resonant tones.
It's pretty tough math and a lot of guesswork with the bell effect and often increased taper at the throat.
All of the aforementioned aspects of the instrument makes a difference in how it plays, but I'm now finding that two often-overlooked areas can make an instrument exquisite, or wreck it's capabilities.
For years, I had done restorative work on Conn "monster" Eb tubas, doing everything that I knew of to make them better players when repairing them, but was consistently disappointed in the low Bb range response. Then, about two years ago, I was working on a restoration of a 1910's Conn monster Eb for GC who is on this forum, and noticed that, after a valve rebuild and repairs, his played remarkably better in that range than any other Conn I'd encountered. At that time, I was just starting to get into the bracing theories, but I noticed that there was one brace that had been omitted at the factory on this instrument that every other Conn had. I had another Conn Eb here, removed that brace on that horn, and immediately had a much-better-playing instrument, a huge improvement.
However, it is not just about having less bracing, either. Some 12 years ago, I did my first BB-to-CC tuba cut job, and although it played well-enough to get by, there were three or four notes that had to be played with, not terrible, but required more effort to play well. I received the instrument back into my shop about a year ago, and after two rounds of re-bracings, the instrument is as consistent throughout as just about any production model and more resonant overall, by adding 12 braces throughout the instrument. I have experimented with theories of bracing, and there is a consistent pattern. If lengths of tubing are allowed to vibrate that are of such a length to interfere with a given pitch, the result is an acoustic interruption which will make the given pitch feel sharp, flat, or damage the resonance. As in the case of eutubabone and his Meinl-Weston F-tuba from the early 1970's, introducing a brace to dampen an unwanted vibration results in the instrument being able to clearly produce the desired pitch without interference.
With the former Getzen G-50 parts, I have spent months fine-tuning the bracing pattern for my CC tuba, which has led to a consistency of response and pitch (and pitch clarity) that is pretty rare.
As for the bass tuba, I have a 1932 Conn monster Eb body and a new-old-stock Boehm & Meinl .689" valveset, and I plan to try to build a really exquisite large F-tuba later this year. I think that with enough work, an F-tuba that size can be made that will "do it all".
Oh, and the second aspect is that horns do not respond as well, particularly in the low range, if they are not soldered together well, and if they leak. As any woodwind player how much they like playing an instrument with leaks - it is the same for us, too, although sometimes they go undetected.
I've recorded my-selves (solo) a couple of times, and it sounds good (as in how good my playing is)
It's when others chime it feels crap, but sound is not very much affected.
You just have to trust what you're doing.........if that can be trusted of course.
Tried the Norwegian Star, and it had the phenomena too....just not Øystein Baadsviks model
