Part 3: Construction Guidelines, All Drums

To pick the right head to achieve desired sound, you should consider the inherent character of your drum. All of what I consider the important aspects of construction is covered in greater detail as you read through the bible. Here are some simple rules to know:

1. The rougher the interior, the less resonant the drum. Just like putting carpet on a wall, rough interiors break-up and absorb reflections.

2. Thinner shells are more resonant. Because there is less mass, they are easier to excite, much the same as bending thin wood is easier than thick lumber.

3. Sharp bearing edges means more overtone and resonance.

4. If the drum is void of obstructions inside, that is, no reinforcing hoop adhered to the inside; the drum will be more open and vibrate more freely. Conversely, if the drum has reinforcing hoops inside, it will have a shorter decay/sustain and a more mid-ranged presence or attack than unobstructed shells. The reinforcing or counter-hoop stifles the ability for the drum to resonate, thus decreasing the low-end along with the very high-end response to a small degree. Therefore, the unobstructed shell is usually brighter or with more high frequencies, while the thin unobstructed shell increases low-end resonance as well.

5. A “better” sound is what you want the drum to sound like and despite the marketing propaganda; less expensive does not mean an inferior sound. Low cost drums are usually a “punchy” type sound due to wood grades used. If recording, this may be exactly what you want in a drum.

6. Mainstream Material, Wood Sound Explained: First, these are general guidelines, which are greatly enhanced by the thickness of the wood used. So if you apply the rules given above, and some common sense, the following will hold true or aid in choosing a drum. Maple compared to African Mahogany: Mahogany will have an approximate 20% increase in low frequency resonance over the Maple drum, mid and high frequencies will be the same from a reproduction point of view.

Maple compared to Birch: Birch will have about a 10% loss in reproduction of low end compared to Maple and about a 20% increase in the high end, with the mid range remaining about the same. So the Birch kit will definitely be a “harder” and “brighter” sounding kit. Beech is in between Maple and Birch.

All other Maple colored woods used in laminated shells are basically there for either structural integrity or looks and do not have the desired qualities (meaning density and grain structure) of the above. Mahogany has earned an undeserved bad reputation due to the use of inferior grades such as Luann on low cost drums for appearance reasons.

Bearing Edges

For many reasons, this is a very misunderstood area of the drum. The bearing edge is the part of the drum that the head should be in contact with at all times and is the essential element to gaining resonance, or the lack thereof. The problem is, they are hidden from view most of the time.

If you are using a “vintage” set of drums, or any set of drums for that matter, first take into account the era or how they were manufactured and realize that the set was designed to produce a sound that reflects the designer or that, which may have been popular with the times.

Anyone can very quickly determine whether his or her set will be able to be tuned to a point where it can be very resonant, excluding the abilities of the tuner and head used. If upon further investigation you determine that your set has been constructed so that a built-in problem or construction technique exists, rethink your desire to put new heads on your drums in hopes it will sound like something in your head because it simply may not be able to be achieved by changing heads, in other cases certainly changing heads may work.

By simply removing the drumhead on any given drum, the answer will be visually right there, staring you in the face. Many older sets were manufactured with a bearing edge that has anywhere between a 35 to 60 degree chamfer cut on the interior side of the shell. On the outer side of the shell, in many cases the bearing edge is rounded over on the outside and crown area as opposed to that of the newer manufacturing techniques.

Now add a bent or deformed hoop to this and I don’t care what head you pick, it will always have a “thud” element to the sound. The closer you move to flatter bearing edge or a bearing edge of 35 degrees on the outside or inside, or rounded as the case may be, the drum will exhibit more of the “thud/cardboard” sound. With newer drums, which usually are a 45 with a very small radius of less than 1/16 of an inch (some kicks very as do snares), resonance is easy to achieve and the head selections I have given will hold true. It is the designers tool to get the drum to produce it’s signature sound.

The key is not the shape of the cut as much as it is what interacts with the head under tension. It’s that fine line of an area right after the head breaks towards the inside of the shell and what remains in contact or can contact the head underneath and interfere with the tone around the circumference.

If you take your finger and lay it lightly on the surface it has an impact on muffling the sound. If the bearing edge has a contact patch of say .03125″ or 1/32nd of an inch, the contact area on a 12″ drum head is 1.17 square inches, or the same thing as taking the tip of your first index finger to the first joint and laying it on the drumhead. Now if you double that to what seems to be an insignificant 1/16″ (twice my 1/32nd example) can imagine how little a change in the contact of the bearing edge surface has on the impact of the sound. In our example, it would be like laying two fingers on the drum.

These kinds of differences can make big changes in the tone of the head. So again, its not so much the angle or being double cut (although this can determine where the bearing edge falls on the head), its what contacts the surface at tension and the treatment of the crown of the edge. A 35-degree cut allows greater contact thus a drier sound vs. a 45, which can be a more resonant sound. Many snares purposefully use a 35-degree cut. Sharper or steep is not always better; it depends upon what you want.

Then you have the limitations of what the wood and how it will tool to consider, which ply it falls on, etc. I leave any tooling of a bearing edge up to a professional because it’s easy to get flat spots or inconsistent angles without proper tools or fixtures.

So my advice is that before you spend, spend, spend on new heads, take 10 minutes and really observe what you have in the bearing edge department. It will not be enough to see 2-45’s degree angles on the drum. They must be even, very even. The drum must be round, very round. They must be consistent in that the profile is the same all around. For example, a round over of 1/16 in one area and a round over of 1/8th in another is a sure sign of trouble.

If one of the chamfer cuts looks wavy, the round over will not be consistent nor will it be truly round. The drum must also sit flat on a hard surface. Lay black paper on a flat hard surface and shine a light from the inside to check. If everything is consistent, this is the mark of a good candidate to get tone from the shell. If not, before you spend money on heads, consider spending the $30 to $60 per drum to have the edges re-cut. It’s money well worth it..

Shell Depth versus Diameter

Note this Correction: The recent version of the Drum Tuning Bible that appeared here prior to January 23rd, 2000, under this section, inadvertently stated the value for square inch of shell area as a value equal to cubic inches. I apologize for the error and this section is now correct. (Prof.Sound)

The shell depth while having an impact on the warmth or resonance of the drum has a greater impact on volume and articulation. The diameter has a far greater impact on creating lower pitch. Greater depth increases volume or power by having an impact on resonance of the fundamental note of the shell. A shallower shell creates a shorter burst of tone and makes a drum more articulate by virtue of the fact that the quantity of surface area of the parent material (i.e. the shell) is lessened and therefore cannot resonate as much as large surface area.

Less distance between heads means the opposite head (i.e. Resonant head) reacts quicker, or gets excited faster when striking the batter head, it responds better to softer playing. For instance, a 22″ diameter kick drum of 16″ in depth has a shell area of approximately 1,106 square inches. A 22″ diameter kick drum of 18″ in depth has a shell area of approximately 1,244 square inches, or a 12.5% increase in area to resonate. Take that same thought to a 10″ tom with a 9″ depth. This results in a shell area of approximately 282 square inches versus one with an 11″ depth, which results in a shell area of 346 sq. in. That 2″ increase in depth is now a 22% gain. The deeper the shell, the more likely they are to produce a deeper or warmer sound because of resonance ability, but this should not be confused with a low tuning.

As for diameter, you have to think about your approach to tuning and overall sound desired. This further explained in the sections “Musical Notes for Tuning, Suggested” and “Interval and Drum Sizing”.

Hoops/Rims

1. Die Cast Hoops: Thicker and stronger then triple flanged stamped hoops with an ability to allow more even tuning of the head and as a result, the head is usually more responsive throughout the tuning range with less varied overtones. As such, may create a slightly drier sound on thin shell, small sized drums due the weight of the rim causing the drum to vibrate less freely. They can also be made out of differing materials such as nickel or aluminum and all aid in changing the sound of the drum.

2. Triple Flanged or “stamped” hoops come in a variety of metals, which affect the tone of the drum. The thinner they are the more difficult they’ll be to tune with. Many drummers prefer these on toms because of the ability to tune “fatter” or “warmer” than with cast. Aluminum makes for a higher pitched tone than does steel and as a result is used on snares quite a bit for a great “crack”. Brass makes the drum more musical and aids in the presence or high-pitched overtones.

3. Wood Hoops have the virtue of being either rigid or flexible, depending upon the manufacturer’s thickness of the hoop. As a result, they can take on the tuning characteristics of a cast hoop if rigid or flanged hoops if thin in construction. However, the rimshot sound is considerably different and acts like an extension of the shell so the drum is usually both more resonant and brighter.

4. Less lugs means fatter tuning and more complex overtones. The longer the interval between lugs the less likely you are to get the head tuned evenly between lugs.

5. A hoop of “rigid” nature results in a head, which can be tuned more evenly between lugs and will accentuate the imperfection in your drum if out of round or bad bearing edges. Sometimes, this causes a drier or more muffled sound as a result of inferior bearing edges.