# Physics in Drumming

1. Dec 22, 2003

### Sko

In drumming there are 2 conflicting points of view-New School (1980's to present; referred to as NS from now on) and fading Old School (dominated 1960's-1970's; referred to as OS). OS's techniques are generally more founded in physics.

I'm gonna go through some of the physics in drumming 1 issue at a time and was hoping for some of the more knowledgeable to eloborate/correct....

The OS place their fulcrum (thumb and forefinger) about an inch from the CG, and NS place their's usually about 2 inches from the end. Since rotational inertia (tendency of an object to resist change in its rotational state of motion) for an object rotating about its CG (OS style) is $$I=\frac{1}{12}mL^2$$ and $$I=\frac{1}{3}mL^2$$ for a object rotating about its end, OS'ers will be able to start and stop their stick faster than NS'ers (more control).

2. Dec 23, 2003

### Sko

Ok, now I have a question for you...

There are 2 main types of drum heads, kevlar and mylar. Kevlar is very stiff (used in bulletproof vests) and mylar is more flexible (used in weather ballons). Which can produce more variation in magnitude of sound (haven't done this in physics yet maybe not the right term)? If it's possible to explain which can produce clearer notes?

3. Dec 24, 2003

### krab

Re your second post, more compliant material allows higher frequencies, so I'm guessing the mylar heads will give a brighter sound.

Re your first post, you are leaving out some of the physics. The drumstick itself has vibration modes too. The NS technique places the fulcrum nearer the node, allowing the drumstick to vibrate more freely. My guess is that although this is nice when drumming close to the stick's natural frequency, it impedes other beat rates.

4. Dec 24, 2003

### Integral

Staff Emeritus
Density of the drum head is only one of the parameters which would effect the frequency of vibration. A drumhead can vibrate in many different modes. The mode of vibration determines the frequency and amplitud of the vibrations. Other factors are tension, how the head is fastened, area of the head and even where and how hard you strike the head.

Given equality in all other factors I believe that the denser material will vibrate at lower frequencies.

I would interpret "Clearer notes" to mean fewer harmonics. This is a hard one to call. More harmonics are generatated when greater forces are involved.

I am not sure how "Stiffness" enters into the equations, that would be different from density, perhaps someone else can add something.

5. Dec 24, 2003

### Sko

I'm assuming stiffness would increase the force exerted on the head and the stick, but cut down on vibrations.

6. Dec 24, 2003

### Sko

Also ever heard of moment of inertia and how it would relate to drumming?

7. Dec 24, 2003

### Integral

Staff Emeritus
Moment of intertia has to do with thing rotating, your drum stick has a moment of inertia that effects how it spins. Not sure that has anything to do with drumming, only the visual effects!

8. Dec 24, 2003

### Sko

http://users3.ev1.net/~rbeckham/m1.jpg [Broken]

Heres an article that talks about it im not sure I understand it tho...

Last edited by a moderator: May 1, 2017