There has been a ongoing debate between players and physicists concerning whether or not materials effect the tone quality of a wind instrument. Most (not all) physicists say the material makes no difference as long as it is smooth and sufficiently rigid. The players say that they can hear a tone quality difference between various materials and wall thickness'. Being a designer and builder of Flutes and Saxophones, this debate is of great interest to me. I have made instruments of various materials and wall thickness' including glass, aluminum and stainless steel as well as brass and precious metals. I also use all the artistic, dimensional/scientific knowledge that is available to me and I have been very aware of the conflict between the artists and the scientist communities concerning the matter of tone and materials. Lengthy papers have been written and questionable tests have been made. I say they are questionable because the exact same blowhole was not used for each separate material being tested. No two blow holes or headjoints are identical and very small dimensional changes will alter the tone.

So in order to find out the truth I constructed the necessary tools and performed some bind tests. The instrument is a fully hardened Sterling silver, keyless flute with .020" wall thickness weighing approximately 260 grams (lightweight because of the lack of keywork). The object of the test was to determine if the weight of the flute would change the tone. If the weight would change the tone then materials of various densities or wall thickness' would also change the tone. Since it is thought to be impossible to create two identical flutes and headjoints, only one flute was used and weights were added and removed. The weights were created by soldering two semicircles of lead (approx 50 grams each) to a pair of flute pad clamps. This way the weights could be removed and replaced quickly and securely. The flute was suspended by strings from two microphone boom stands and the player was not allowed to support the flute in a vertical manner so that he/she could not sense any change of weight during the testing. Earmuffs were worn during the weight change to mask any noises that would indicate whether the weights were being added or removed (this was probably unnecessary). A keyless flute was chosen so the player would not have to support it in his hands (while holding down keys) and sense the change in weight. The player was only allowed to push the flute horizontally against his lips. A blindfold was used to prevent the player from seeing the weights.

A helper would toss a coin to determine if the first turn of each series of tests was started with the weights or without them. The influence of verbal cues were eliminated by taping the player on the foot when it was time to blow. The first blow was always named "A" and the second was named "B", then back to "A" etc. The helper would change the weights whenever the player indicated that he was done blowing and was ready for a change. The player would say "A" or "B" each time in order to keep track. After sufficient testing the player would describe the difference in tone between "A" and "B". The test would be repeated by flipping a coin to determine if the first "A" blow would be with or without the weights. The player would have no clue of the coin toss results or if weights were on/off when starting and throughout the test.

Any professional player who is sensitive to flute tone can make this test. A beginner or an insensitive player may not be qualified.

When I made the test I was totally unaware of any weight change. I listened carefully for any tonality change and noticed that even though the volume remained approximately the same between the "A/B" tests, there was a noticeable change in darkness/brightness of tone. Another way to describe it would be "carrying power" or "solidity" as compared to "airy, and scattered". Other people may describe the difference in different ways - perhaps a shift in the overtones, more or less focus, resistance or projection. I would go back and forth up to 10 times before saying that either "A" or "B" was a deeper/darker or brighter/thinner tone. Then we would start over with a coin toss. For the first three series (coin tosses) I matched the un-weighted turns as being brighter and the weighted turns as being darker in tone. In the forth series I was over confident and I made up my mind on the first blow - and I contradicted my first three tests. I took more care during series five and six and in those I again matched the weighted turns as sounding darker and the unweighted turns as sounding brighter.

These initial tests indicate that weight, wall thickness, density/mass does indeed have an effect on the tone of a musical wind instrument. If musicians are hearing something that they care about, then they will choose their instruments accordingly. Those scientists/physicists who say that material doesn't make enough of a difference are wrong if the players can prove otherwise - and it appears that they can. Perhaps the sceintific mathematical formulas are not taking into account the sensitivity of the artist's ear, or they are simply missing something. Either way - "the proof is in the pudding" and people (artists) know what they like.

The next step would be to measure the tonal spectrum differences of the tests and relate this to the sensitivity of the artist - then the scientists/physicists would have something to work with and add to their database. If artists can distinguish fine tonality then comparisons can be made with correspondingly fine measuring devices. Testing with less weight would show just how sensitive some players are. Just saying "material doesn't make a difference" is an over-simplified and inaccurate statement.

Another interesting test would be to fabricate a lip plate/chimney so that it clamps (and seals) onto various tubing materials - each with a hole for the chimney. That can be someone else's project.

I encourage other artists and scientists to duplicate this test. Strict controls can be enforced as long as they do not destroy the artist's ability to play and hear with accuracy. I will make my tools available (up to a point) to those who come to my location (central California). Sensitivity of the player should be considered. This test is aimed at those who are particular and sensitive about flute tone - not beginners or those who have not developed a distinguishing ear.

There has been some speculation concerning tube vibration and how that may influence the blind test. I made some vibration tests and found out some interesting things. I have a tube without toneholes and I have another tube full of toneholes called the "PAD TONE TESTER" that I developed for testing the tone of pads.

Click here for details about "THE PAD TONE TESTER"

These tubes are the same length and play low B but they behave very differently. The "tone tester" without toneholes has very little vibration when played - it is barely detectable. The "pad tone tester" with its many toneholes is another story. Vibration is obvious and pronounced. The tube buzzes in your hands even more than a conventional flute. It should also be noted that a conventional flute also vibrates much more than the "tone tester" without toneholes and the vibration of the flexing body is transmitted up to the headjoint.

The extra vibration is probably due to the toneholes weakening the tube and allowing it to flex and vibrate more than the tube without toneholes. The tone of the tube without toneholes sounds much better than the perforated "pad tone tester" - this is probably due to the dampening effect of the pads and the air-flow interruption of the toneholes. In this case the extra vibration coincides with poorer tone. Adding or removing weight had no noticeable affect on the amount of tube vibration.

My theory is that if the flute (or the pads/keys) vibrates too much, it will dampen out the vibration of the air column, rob energy and hurt the tone. Conversely, a stiffer thicker heavier tube does not flex or move as much - the air column is forced to do all the moving. But super thick & heavy tubing does not necessarily mean super tone. A practical, medium ideal is more likely.

Another important observation is that when trying to determine the amount of vibration at the headjoint, I noticed that in the case of the "tone tester" without toneholes - it was easier to feel the vibrating air with my lips because of the close proximity of the blow hole. This vibrating air was much more pronounced than any vibration of the head joint tube.