How Bearing Edges Affect the Sound of Your Drums

Over the years, I have helped hundreds of drummers with their drum set purchases, but not one has ever asked me about bearing edges.

The bearing edge—the bevelled rim of a drum’s shell—is the only place where the head meets the body of the drum. When you strike the skin, the energy of your stick transfers from the head through the edge to the shell.

The angle and shape of the edge’s cut determines the amount of contact between the head and the shell, contributing greatly to the resonance and tone of the drum. They also determine the direction of the shell’s resonance, with rounder edges making a shell vibrate outward from the core and sharper edges drawing vibrations inward from the outer wall, according to a 2011 article in Drum! magazine.

I find it interesting that, though drummers will spend a great deal of time considering the best types of wood for their shells, many don’t even think about how the bearing edge will impact that decision. But this is not to say that all drummers neglect the edge. In some corners of the drum world, the angles and shapes of edges are hotly contested. Some drummers insist on re-cutting edges to their liking, while others insist they cannot hear a difference no matter the angle or shape.

Manufacturers like Yamaha and Pearl (on their high-end drums) will cut different edges onto drums of different sizes. Craviotto and some other builders offer hybrid bearing edges, with different cuts for the tops and bottoms of shells. England’s Guru drums have created an entirely new design, offering what they call “timpanic” edges, which look like no other edge on the market.

To my ears, and many others, there are distinct differences. Below, we’ll explain some of the most common bearing edges you’ll find and how they can affect your sound.

The Basic Types of Bearing Edges

45° angle, single— Cut into the inside edge of the shell, a single 45° angle will offer minimal shell contact, which allows the drum head to vibrate longer, thus increasing the drum’s sustain. The limited contact with the shell also provides a sharper, more “modern” sound with increased attack.

Because the bearing edge in contact with the head at a single point, more harmonics can develop, giving the drum a brighter tone. The disadvantage is the drum is more difficult to tune and sounds less warm.

45° Single Cut
45° Single Cut with Countercut

Additionally, there are variations on the 45° single cut, with some manufacturers making the cut all the way out through the outermost ply, while others offer a slight countercut in order to bring the apex farther inward.

Double 45°— This adds another 45° angle from the outer wall to make a sharp point well at the center of the rim, as far inward as you can go. By moving the point of contact away from the outer wall and the head’s collar (where it begins to bend), the double 45° increases the sustain

and allows for a wider tuning range. The disadvantage is that it can be more easily damaged, which can cause unwanted buzzing, deadness, and tuning difficulties.

45° Double Cut
45° Roundover

45° roundover— Drummers looking for that “classic vintage sound” should be looking for rounder bearing edges. The 45° roundover creates more contact between the head and the shell, providing more of an opportunity for the woody warmth of the drum to come to the fore. Many makers still use this style of bearing edge on their jazz and vintage offerings. The disadvantages include less attack, fewer overtones, and less definition.

30°—Like the 45° single, there are variations of style here. But the most common is to have a single 30° angle inner cut meet a rounded profile coming from the outer wall. This cut and shape offers a wide surface area for the head to make contact with the shell, thus offering greater shell resonance and a slightly more wooden tone. These edges, found frequently on older drums, are also more durable than the sharper 45° cuts.

30° Single Cut Roundover
30° Full Roundover

30° full roundover—This offers the most shell contact with the head. These drums are easy to tune, offer the most control of overtones, and give that “fat” drum tone. Many kick drums and floor toms use this type of bearing edge. The disadvantages can be a loss of definition, resulting in muddier tones.

How To Choose the Right Edge For You

When choosing a new drum or kit, I recommend you listen to some well-tuned brands to see what kind of edge you prefer. As most new drums are sold with single-ply heads this allows you to really hear the sonic differences.

Take notes and try not to let the brand’s name or badge influence you. Listen for the fundamental tone, the harmonics, the attack, and the sustain of each type of bearing edge. This will go a long way in helping you to make the best decision.

When purchasing drums (and especially used drums), it’s advisable to look at the condition the bearing edges, regardless of angle and shape. Damaged or uneven bearing edges can greatly degrade the tone of the drum and can make tuning difficult or even impossible.

If possible, take the batter heads off and sit the bearing edge of the drum on a glass table. Glass is totally flat and you can trust it to show any wear or gaps in the bearing edge. If you see daylight under the drum or if it rocks, that means the bearing edges need work. The drum price should be adjusted accordingly.


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