How Wood Density Affects Tonal Quality
How Wood Density Affects the Tonal Quality of a Love Flute
The sound created by a wooden flute, like the Native American style flute, is not dependent on the vibration of the wood itself. With a guitar or violin the sound coming from the instrument is dependent on how the wood out of which the instrument is constructed vibrates. The vibration from the string stimulates the wooden body of a guitar. The guitar body begins vibrating in harmony or concert with the string. The vibrating wood then amplifies this vibration and projects it out into the surrounding space.
A wooden Love flute creates and projects sound differently. The wooden flute does vibrate somewhat. You can feel this vibration with your fingers when you play. But this vibration is not where the sound of the Native American flute that your ear hears comes from. The sound of the flute comes from a vibrating air column inside the flute. This vibrating air column pushes pulsating air out of the holes of the Love flute. The holes out of which sound comes are the primarily the hole at the end of the barrel of the flute and the hole called the true sound hole. When a finger is lifted from a tone hole this hole is then available for pulsating air to exit the flute. It is these sound pulses/vibrations that reach and stimulate your eardrum and create the sensation of sound.
The body of the Love flute acts as a resonance chamber.
A speaker box is a resonance chamber. As with the Native American flute the sound does not come from the speaker box itself resonating. The sound comes from the pulsating speaker cone. Speaker boxes (at least in the old days) were made out of dense, hard plywood. A dense, hard wood was used so that the box itself would not absorb sound vibrations. If the box were to absorb sound vibrations the tone coming from the speaker would be somewhat muted.
A Native American style flute, like a speaker box, is a resonance chamber. Therefore if the Love flute is made out of a softer wood the body of the flute will absorb some of the sound vibrations. Some of the vibrations are lost or absorbed into the wood of the flute itself. As a consequence of these vibrations lost to absorption the sound coming out from the holes in the flute will be muted somewhat. The wooden body of a Love flute absorbs different types of vibrations selectively. Softer wood tends to absorb higher overtones. Lower overtones are less affected. This accounts for the so-called mellow tone of a cedar or other soft wood flute.
If we are concerned with obtaining as much fidelity of tonal quality as possible then we want a resonance chamber with absorbs the least amount of overtones – both high and low. A dense, hard wood is best for this. That is why the best clarinets, wooden flutes, bag pipes etc are made form African blackwood or another type of dense hardwood.
Soothing sound quality
The tonal quality of the Native American style flute has come to be associated with a soothing sound quality. All Love flutes are soothing in comparison to an instrument like the clarinet or saxophone. I prefer a Native American style flute that has what could be called a warmer and brighter tonal quality. For me this means that a flute that generates and preserves the higher overtones can. I want tonal brightness (brightness is often equated with sweetness) but not so much that the sound becomes hard and dry. So for higher keyed Love flutes (B, A, G, F#) I prefer a medium density hardwood like African mahogany, cherry, soft maple. Walnut is a bit too soft for me. I tend to avoid purple heart, bubinga, bloodwood, African blackwood and santos mahogany for these keys. For lower key Native American style flutes where the sound tends to be softer I prefer a harder wood that preserves the brighter aspects of the sound.
These are just personal preferences and different Love flutes will react differently independently of the wood type they are made of. This is on of the many mysteries of Native American flute making. I hope I haven't confused you. I just thought I’d give you something to more ponder on as you gaze lovingly at your flute and fondle it in your hands before putting it to your mouth and breathing living sound into existence.