Flouting the Flautist!

[Szykneij]

... not quite, but I wanted to come up with an eye-catching alliterative title.   

My colleagues and I were actually having a civil debate on an issue, so I thought I'd pose the question here to let other GMG'ers' weigh in.

For most musical instruments (which vibrate to create sound or in response to the notes produced), the material used in construction is a major factor in their overall tone quality.  Clearly, a violin crafted from  fine aged tonewood will sound better than a violin made from inferior materials.

But, in the case of the flute, which produces sound through a vibrating air column, it's my contention that the material used in making the instrument has no affect on the quality or timbre of the tones produced. Given all other factors (design, workmanship, pads, springs, etc.) being identical, a flute made of silver, gold, or platinum should sound no different from one made of glass, plastic, or any other material with a smooth finish.

One colleague disagrees and feels her silver flute has a sweeter tone than her alloy instrument, but I attribute this to factors other than the construction material. What do you think?

[EigenUser]

... not quite, but I wanted to come up with an eye-catching alliterative title.   

My colleagues and I were actually having a civil debate on an issue, so I thought I'd pose the question here to let other GMG'ers' weigh in.

For most musical instruments (which vibrate to create sound or in response to the notes produced), the material used in construction is a major factor in their overall tone quality.  Clearly, a violin crafted from  fine aged tonewood will sound better than a violin made from inferior materials.

But, in the case of the flute, which produces sound through a vibrating air column, it's my contention that the material used in making the instrument has no affect on the quality or timbre of the tones produced. Given all other factors (design, workmanship, pads, springs, etc.) being identical, a flute made of silver, gold, or platinum should sound no different from one made of glass, plastic, or any other material with a smooth finish.

One colleague disagrees and feels her silver flute has a sweeter tone than her alloy instrument, but I attribute this to factors other than the construction material. What do you think?

This is very interesting, especially since I studied mechanical engineering in college and this relates to second-semester fluid mechanics (the topic being "internal flow" in a pipe as opposed to "external flow" over an aircraft wing). I love this stuff.

Now, I have no idea of the answer, mind you, but perhaps the "smoothness" has something to do with it. It is well-known that various materials have various roughness coefficients. This is used in computing the Darcy friction factor. Although I am not sure (the goal of fluid flow in my class was to move fluid from one place to another, not to make a pretty sound), this friction factor almost definitely is a factor in determining things relating to vibrations. Unless you are an Incredible Flautist ( ) we're dealing with subsonic flow, so using the Moody chart will be okay -- I forgot if this works for compressible/supersonic flow or not, but it won't matter here.
http://en.wikipedia.org/wiki/Moody_chart
http://en.wikipedia.org/wiki/Darcy_friction_factor

Like I said, I have no idea how much the friction factors would vary from one common flute material to another. If they vary significantly, though, then it is likely true that the sound quality is affected.

[Szykneij]

I'm not sure how important friction is because, while the air column within the instrument is vibrating, it is not technically flowing through the instrument like water through a hose. The air the player passes over the embouchure hole is what sets the column in motion, so, if anything, the headjoint material might be more of a factor than what the flute body is made of.

[EigenUser]

I'm not sure how important friction is because, while the air column within the instrument is vibrating, it is not technically flowing through the instrument like water through a hose. The air the player passes over the embouchure hole is what sets the column in motion, so, if anything, the headjoint material might be more of a factor than what the flute body is made of.

That's true, this is a flute we're dealing with. It's more like blowing over the top of a bottle than blowing through a straw (e.g. oboe, clarinet).

[Karl Henning]

I should verify with my flautist friend . . . for some reason I am recalling a story of a flautist playing behind a curtain, and when he emerged to the stunned audience, he had been playing on an instrument made of concrete.

[Gurn Blanston]

Perhaps there is some reason other than construction materials which causes a wooden flauto traverso to sound mellower, i.e. - less shrill than a flute made of metal? Maybe it is the placebo effect in action. skilled players of a traverso are also able to 'bend' notes which they can't do on a metal flute, although that isn't anything to do with the tonal quality, per se. I'm not championing a cause here, I'm as curious as anyone. 

[SonicMan46]

Perhaps there is some reason other than construction materials which causes a wooden flauto traverso to sound mellower, i.e. - less shrill than a flute made of metal? Maybe it is the placebo effect in action. skilled players of a traverso are also able to 'bend' notes which they can't do on a metal flute, although that isn't anything to do with the tonal quality, per se. I'm not championing a cause here, I'm as curious as anyone. 

Well, I'd have to agree w/ Gurn - love my wooden flute recordings but have never done any A-B blind comparisons - about 5 years ago, I left the post on crystal flutes in the 'Old Musical Instruments' thread - now I've not played that CD in a long time, but I recall the sound having a 'bell' sound; even emailed our fellow member Jochanaan an audio snippet (MP3) off the recording - hopefully he'll 'chime in' as a flautist!    Dave

Crystal Flutes - below is a post quoted from the 'old' forum from the end of 2005 - another fascinating older instrument - have not listened to that CD since then - but the playing is distinct & different; here's a link to Old French Flutes - just scroll down the page to some discussion & pics of the crystal ones - 


 

[Florestan]

A flute produces sound when a stream of air directed across a hole in the instrument creates a vibration of air at the hole.[32][33] The air stream across this hole creates a Bernoulli [effect], or siphon. This excites the air contained in the usually cylindrical resonant cavity within the flute. The player changes the pitch of the sound produced by opening and closing holes in the body of the instrument, thus changing the effective length of the resonator and its corresponding resonant frequency. By varying the air pressure, a flute player can also change the pitch of a note by causing the air in the flute to resonate at a harmonic rather than the fundamental frequency without opening or closing any holes.

To be louder, a flute must use a larger resonator, a larger air stream, or increased air stream velocity. A flute's volume can generally be increased by making its resonator and tone holes larger. This is why a police whistle, a form of flute, is very wide for its pitch, and why a pipe organ can be far louder than a concert flute: a large organ pipe can contain several cubic feet of air, and its tone hole may be several inches wide, while a concert flute's air stream measures a fraction of an inch across.

The air stream must be directed at the correct angle and velocity, or else the air in the flute will not vibrate. In fippled or ducted flutes, a precisely formed and placed windway will compress and channel the air to the labium ramp edge across the open window. In the pipe organ, this air is supplied by a regulated blower. In non-fipple flutes, the air stream is shaped and directed by the player's lips, called the embouchure. This allows the player a wide range of expression in pitch, volume, and timbre, especially in comparison to fipple/ducted flutes. However, it also makes an end-blown flute or transverse flute considerably more difficult for a beginner to produce a full sound on than a ducted flute, such as the recorder. Transverse and end-blown flutes also take more air to play, which requires deeper breathing and makes circular breathing a considerably trickier proposition.

Generally, the quality called timbre or "tone colour" varies because the flute can produce harmonics in different proportions or intensities. The tone color can be modified by changing the internal shape of the bore, such as the conical taper, or the diameter-to-length ratio. A harmonic is a frequency that is a whole number multiple of a lower register, or "fundamental" note of the flute. Generally the air stream is thinner (vibrating in more modes), faster (providing more energy to excite the air's resonance), and aimed across the hole less deeply (permitting a more shallow deflection of the air stream) in the production of higher harmonics or upper partials.

Head joint geometry appears particularly critical to acoustic performance and tone,[34] but there is no clear consensus on a particular shape amongst manufacturers. Acoustic impedance of the embouchure hole appears the most critical parameter.[35] Critical variables affecting this acoustic impedance include: chimney length (hole between lip-plate and head tube), chimney diameter, and radii or curvature of the ends of the chimney and any designed restriction in the "throat" of the instrument, such as that in the Japanese Nohkan Flute.

A study in which professional players were blindfolded could find no significant differences between instruments made from a variety of different metals.[36] In two different sets of blind listening, no instrument was correctly identified in a first listening, and in a second, only the silver instrument was identified. The study concluded that there was "no evidence that the wall material has any appreciable effect on the sound color or dynamic range of the instrument".

A more detailed technical analysis can be found here.

Hope it helps.

[Szykneij]

A more detailed technical analysis can be found here.

A study in which professional players were blindfolded could find no significant differences between instruments made from a variety of different metals.[36] In two different sets of blind listening, no instrument was correctly identified in a first listening, and in a second, only the silver instrument was identified.

... and this could be attributed to the fact that a silver flute would feel lighter to the player, and not to the sound of the instrument.

Great info, thanks!

[Florestan]

Great info, thanks!

My pleasure!

[Karl Henning]

And, on those lines . . . when I went to Peter's for rehearsal one afternoon, he had as a houseguest a flute-maker from Alaska.  One of the instruments he had brought with him was a bass flute, made of some much lighter material (which Peter remarked would cut down on the potential for fatigue in stars & guitars . . . .)

[jochanaan]

Oh, the type of metal used does affect a flute's tone.  I've heard a gold flute live; rich, mellow sound, much more than I can get on my ancient student-line flute.  I've only heard a platinum flute on recordings (the 1970s Elaine Schaffer recording of Bach's Sonata in C Major; old Philadelphia Orchestra recordings when the legendary William Kincaid was principal flutist), but it's massive, tending to overpower the other instruments in Ms. Schaffer's Bach.  I suppose these denser metals enclose the vibrational air field more effectively and tend to vibrate less than silver or steels, thus causing the sound to project more.

But I tend to think that construction affects the sound more.  I've played a flute owned by a colleague who had an online flute shop (she's now retired from the shop although she still plays); this flute had a mouthpiece with a narrow, flexible tongue of metal on the tone hole's rim opposite the player's mouth, and its tone was just amazing!  If I only had $15,000 or so...

Wood instruments are undeniably mellower in sound, from both material and construction.  I can hear the difference even on YouTube.

[Karl Henning]

Thanks, jo!  No substitute for asking the chap who knows