Tech/maintenance Tone holes

[gladsaxisme]

Just a thought, I know that the different notes on a sax are formed by having tone holes at various distances along the length of the sax,but while I have been stripping old saxes down I have noticed that the size of the various tone holes of the same note can be completely different from one sax to another is there a logical reason for this or is it just that this particular manufacturer thinks you get a beter note with the hole at this particular size or is it some mathamatical thing...john

 

[kevgermany]

The starting point for this is that the tone holes need to be a certain size, relative to the tube diameter at that point, to get the sound wave to behave as if it's come to the end of the tube and not rush past. So an extreme example - Bottom Bb is a lot bigger than top Bb.

Then on top of that the effectiveness is changed by whether the holes below the current one are open or not. If the holes below
the current one are normally open (e.g. F has E & D open below it) then you can get away with a smaller tone hole than would otherwise be the case. And vice versa, a tone hole tha normally has a closed one below it or two below it needs to be bigger.

Other factors as well.

So it's a complex exercise. and the only real answer is to start reading up the theory....

 

[Pete Thomas]

and the only real answer is to start reading up the theory....

Or make a saxophone by trial and error.

 

[Koen88]

So it's a complex exercise. and the only real answer is to start reading up the theory....

Or make a saxophone by trial and error.

or both?

 

[thomsax]

Interesting question. I have asked myself the same question. We know that the the size of the tube and the tonehole placement on the body is important for the tone/sound. But how do they know the right dimensions of the toneholes?

I asked Peter Jessen ( http://saxophone-copenhagen.blogspot.com/2008/01/tenor-saxophone-tubing-key-work.html) how he did the tubes and toneholes. He told me he copy a tenorsax that he knew was a good player. His G-mezzosprano is a complete new construction so he had to work it out from scratch. It's is a lot of work to do a prototype. Benedikt Eppelsheim helped him with this.

When LA Sax constructed thier straight tenor they took an old smallbell Martin with soldered toneholes so the could "move" the toneholes on the bell so the tonehole came in right position. I guess the neck and tube/body was a Taiwan construction but the bow and bell toneholes/keys were constructed in USA. I don't know if the sax was manufactoried in USA or Taiwan. I guess Taiwan because the toneholes were drawn on the bell.

Thomas

 

[DavidUK]

Is there any horn perfectly in tune all the way up and down?
Using a tuner I generally find each note differently out of tune, i.e. some in tune, others not all the same amount out of tune.
If each tone hole or pad/cup could be adjusted, in manufacture or after sale to remove this variable so they all play identically in tune, would this be advantageous?
I think I may have a way of doing this.

 

[mizmar]

to get the sound wave to behave as if it's come to the end of the tube and not rush past.

One day I might compile a list of people's physics intuitions which make me smile.

 

[saxyjt]

Is there any horn perfectly in tune all the way up and down?
Using a tuner I generally find each note differently out of tune, i.e. some in tune, others not all the same amount out of tune.
If each tone hole or pad/cup could be adjusted, in manufacture or after sale to remove this variable so they all play identically in tune, would this be advantageous?
I think I may have a way of doing this.

Have you ever read this?

 

[turf3]

If there were no "cross-fingered" notes, then the correct pattern would be for the tone holes to monotonically increase in diameter from the top to the bottom of the horn.

However, we have only 8 fingers available and 12 tones to make, so there are cross-fingered notes. C, Bb in the 1 and 1 fingering, A, F#, E, D are all notes where there are closed pads closely below the first open one. When you have closed pads immediately below the first open one, the first effect is to flatten the note of concern; there are also effects on overtone tuning which are not always easily predictable. The maker then has a choice to enlarge the tone hole that's being flattened, or move it up the tube, or a combination.

Furthermore, in the second octave we rely on the two octave vents to get the overblown notes; because there are only two of these instead of 12, their location is necessarily a compromise. That means that some second octave notes are flat or sharp because of the location of the octave vent, when the same effect isn't present in the first octave. Again, makers can bend that tendency a little bit one way or the other by adjusting tone hole size or position or both.

Finally, the conical shape of the horn is a compromise in itself. First of all, it's not a perfect cone just because you've got all these closed-off tone holes, makeing it a "lumpy" shape. Then you've got deviations from conicity for manufacturing purposes, especially in the bow and the neck tenon. And finally, the cone's cut off at the mouthpiece end, so that there can be some decent volume in the mouthpiece. So all of this creates additional tuning anomalies. A real good example is that on most saxophones the octave between all-open C# in the staff and all-opn C# above the staff is "wide", in other words more than an exact octave; the ratio of frequency is greater than the theoretical 2.000. Prior to the Selmer Mark 6 (it could have been the Balanced Action), most manufacturers designed the tone hole positions and sizes so the lower all-open C# was more or less on pitch, and the upper one was sharp. This is much like the way the same note is on flute. It's not uncommon to put some fingers down in the right hand to flatten that note in slow passages. Selmer with the Mark 6 decided to reduce the sharpness of the upper C#, but in doing so they ended up with the lower C# being flat for many players. Unfortunately it's pretty hard to make a note sharper when all the fingers are already up. Again, this is a matter of tone hole sizing and position.

 

[thomsax]

The saxophone is a compromise when it comes to tuning and intonation. They say that every tone(hole) should have it's own octave key.

Martin Committee saxes have fine pitch and intonation due to the construction with softer soldered tone holes. Vintage saxes the Committees are among the best.

Today new tools and machines have improved the pitch and intonation. All toneholes are more or less drawn today.

Of course a damage or an overhaul can change a sax. Factory set-up is important.

 

[turf3]

The intonation of the horn has nothing to do with whether the toneholes are soldered or drawn. It's about the size, height, and location.

"Tools and machines" don't position the toneholes; designers do. Any of several different ways to fixture the parts and position the toneholes, whether soldered (I don't think anyone does this, except a few of the tiniest holes on the tiniest saxophones) or drawn, will result in tonehole locations whose accuracy falls well within tolerances. There's no special technology in designing such fixtures and tooling.

 

[DavidUK]

@saxyjt - no. Interesting.

@turf3 - so if each note relied on just one tone hole, not multiple, the crescent idea, or mine, may work. But I don't think it can where there's so much cross fingering. Is that what you're saying? Even with multiple fingerings in operation, is it possible to tune each tone hole to suit every combination of these? Or is that down to adjusting tone using your mouth to compensate?

By the way, my idea is to increase or decrease overall air volume inside each tone hole by reducing or increasing the height of the pad or the volume within the pad using a combination of spacers, different reflectors, or "no centre" pads, i.e. just a ring of sealing material. This is all possible with my new pad system.

 

[turf3]

@saxyjt - no. Interesting.

@turf3 - so if each note relied on just one tone hole, not multiple, the crescent idea, or mine, may work. But I don't think it can where there's so much cross fingering. Is that what you're saying? Even with multiple fingerings in operation, is it possible to tune each tone hole to suit every combination of these? Or is that down to adjusting tone using your mouth to compensate?

By the way, my idea is to increase or decrease overall air volume inside each tone hole by reducing or increasing the height of the pad or the volume within the pad using a combination of spacers, different reflectors, or "no centre" pads, i.e. just a ring of sealing material. This is all possible with my new pad system.

Well, first of all the tone holes on a saxophone aren't large enough to fully cut off the air column by just one hole. There was a woodwind instrument a few hundred years ago with very large tone holes where all the keys were normall closed and you just pressed a single key to open a single hole to form a note. However, I can't remember its name and I think it was an obscure sideline. For practical purposes the tone hole size is limited by the loss of stiffness in a tube punctured by many large holes.

It's relatively easy to flatten a single note by using a crescent. However, there are almost always additional unplanned effects.

In the end, woodwind design is a series of compromises. If you want to, you can design a mechanism sufficiently complex that you eliminate cross-fingerings, assign more octave vents more closely, and do a few other things - but then you end up with an enormously complex, heavy, less reliable instrument. Or you make compromises in the sizes and positions of tone holes to ensure that every note is adequately in tune, and then rely on the musician to favor them one way or the other as needed.

For that matter, every single musical instrument except an electronically driven sine wave generator contains numerous of these compromises. Ask around any group of instrument makers for any instrument and you'll quickly learn about the compromises that have to be made.

 

[turf3]

Reed contrabass - Wikipedia

en.wikipedia.org

I found the name and an article about the obsolete "reed contrabass".

 

[mizmar]

If you want to, you can design a mechanism sufficiently complex that you eliminate cross-fingerings, assign more octave vents more closely, and do a few other things - but then you end up with an enormously complex, heavy, less reliable instrument.

Call it a saxophone and try to market it to marching bands. Good luck with that.

 

[jbtsax]

From my reading of woodwind acoustics literature, I have found that toneholes are a complex part of why an instrument plays the way it does, and has been studied extensively. If one googles "tonehole lattice" it will bring up several of the recent studies.

 

[thomsax]

Every toneholes on a sax needs some kind of energy to be done. It can be done by hand (hammered out), by machines (pull up aka "drawn") or soldered on (soft or silver). If the designer prefer "rolled tone" holes more energy must be added. To solder on an "rolled tone hole"when the tone holes are made, can't give us a better sax? Most designers wants broader tone holes rims. "RTH" or soft soldered tone holes gives us broader tone holes rims.

I waiting for a seamless conical brass tube (body, bow and bell). Tone holes that are made with methods that are "friendly" to the brass ..... . It's possible to do that today. But can the saxophone industry carry the costs?

 

[TobyB]

every single musical instrument except an electronically driven sine wave generator contains numerous of these compromises

Except, of course, the trombone. It's perfectly awful. 😉

t
plays trombone