Bearing Edges vs Heads

Soupy

Silver Member
So the common "vintage" design of the modern drum set used somewhat rounded bearing edges with simple unmuffled mylar heads. Rounded edges dampen the sound of the head somewhat on heads which would naturally be highly resonant and tonal. And certainly, additional muffling could be added (with the felt strip being a traditional method).

Contemporary drum sets often use sharp chamfered bearing edges (the "double 45" being typical), which is a design that offers the most amount of resonance and tonality. But the modern drummer also has a wide selection of drum heads with varying amounts of builtin muffling to reduce resonance and overtones.

So it seems like you end up in the same place. Though I guess the modern method has a certain convienient flexibility, as it's a lot easier to change heads or add moongel than it is to recut your bearing edges.

I'm contemplating buying parts and assembling/finishing my own set of drums, so this is running though my head. And it's all really meaningless in the end, because drums will sound like drums no matter what. But I was curious if anyone wanted to comment on my rambling...
 
Since more and more people have become drummers as availability has increased, it's very difficult to make an accurate generalization about the habits of today's drummer. As the majority of the members on this board will tell you, resonance is the ever-elusive beast that they're trying to permanently capture.

If you want a very resonant drum shell, then you might want to buy a bunch of Ambassadors and get the most exact 45º bearing edge on those shells you can muster. Anything else is obvious from that point. Thin shells also help.
 
I can see both sides. Those rounded bearing edges give a kind of punch that I really haven't heard anyone achieve via muffling or head choice. But they aren't as versatile to my ear. I prefer the more open, resonant tone of sharper bearing edges for most purposes, so I would choose them. When I wanted the sound the rounded bearing edge, I would approximate it with muffling.
 
What the rounded edge does that a more muffled head can't do is bring in more sound of the shell, by increasing the amount of contact between the head and the shell. The trick is to find the balance between achieving a good tone and allowing the head to ring. And that's where shaping the edge is as much art as it is science.
 
What the rounded edge does that a more muffled head can't do is bring in more sound of the shell, by increasing the amount of contact between the head and the shell. The trick is to find the balance between achieving a good tone and allowing the head to ring. And that's where shaping the edge is as much art as it is science.
Absolutely the truth! Muffling the head (either by external means or head construction) only controls the head. The observation of it being a combination of art & science is so true, mainly because many of the results are difficult to measure or verify.
Also, it's not a two choice thing, rounded or sharp. There are hybrid edge profiles that offer both a sharper edge for sustain, plus extra head contact through the washout. Then there's the possibility of having different bearing edges on the batter & reso, thus assigning a defined role to each head. On top of that, there's "out there" theories that seek to isolate the element functions of the drum components to further define their overall sound contribution, refine control & reduce unwanted overtones. No simple answers, such is art, context, & subjectivity.
 
round bearing edges transfer better the low vibrations, so you have more tone actually and low end but you loose sustain.
I think a killer combo would be round edges fot the batter side and 45º for the reso
 
Also, it's not a two choice thing, rounded or sharp. There are hybrid edge profiles that offer both a sharper edge for sustain, plus extra head contact through the washout.

Woah! I've never heard of this before. Can you post a picture, or at least a link, to a drum that has a simultaneously sharp AND rounded bearing edge? This I'd like to see...
 
Woah! I've never heard of this before. Can you post a picture, or at least a link, to a drum that has a simultaneously sharp AND rounded bearing edge? This I'd like to see...
Dammit, I don't have anything I can post that offers a visual representation, but I can try to explain. First, a bit of background. I've been working through ideas with Dean of Guru Drumworks. He already, & very successfully uses this principal on many of his drum constructions. The precise point at which the head meets the bearing edge dictates the behaviour of the head when struck, & is so much more than the simple angle designation attached to different bearing edges. In fact, IMO, the angle has very little to do with the edge itself, it's more of a crude measure of sharpness & an indication of the contact footprint under oscillation. Far more critical is the radius of the contact point itself. All bearing edges have a radii of some description, it's just a question of size. For example, if I want Dean to use a 45 degree edge, I'll specify it as a 45 degree with R1, R1.5, R3, etc. The difference that radius makes is huge. Sorry for the slight tangent, but that aside, if you take a standard 45 degree edge of whatever radius, the outer part of the profile is usually 45 degrees too. Commonly referred to as a double 45. Dean often uses a generous radius on the outside edge profile such that the head material between the bearing edge contact point & the aluminium rim of the head is in almost complete contact across it's surface area. On a standard double 45 profile, that head material is usually in suspension. The result is a sharp/defined contact point profile that dictates the behaviour of the head in oscillation, and a big surface area of head material in close contact with the shell material.

Dean is not the only builder who does this, but it's certainly not common mass production practice. The end result is a modern "wet" attack & long sustain, but with a vintage thump & greater shell involvement. If you look at the last picture on this thread http://www.drummerworld.com/forums/showthread.php?t=72780 you'll see a closeup of the bearing edge on the reso side of my latest snare from Dean. OK, it's not easy to see, but look to the outside of the obvious head contact point, the area in shadow thereafter is a big radius. Aslo, if you look up the specs, you'll see my reference to radius on washout & the different contact point radii specified for batter & reso heads. To be honest, a snare is not a great example to use, as the differences are small, especially at higher tensions. The difference on thin shelled toms is very pronounced indeed. I've done the comparisons.

Who needs muffling when you can achieve everything you want through correct bearing edge specifications!
 
Some photos...................
 

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Call me skeptical, but it seems impossible to have the bearing edge cut as both a sharp cut AND a rounded cut at the same time...they are two different things. I'm just wondering if there's something I'm missing. The pictures that the good mayor posted show sharp, rounded, and in one case, a flat edge.

Are you referring to the round-over by chance? I'm not quite following...
 
I am from the school that separates sharp from rounded bearing edges.
I own both round edge and sharp edge drums.
They are apples and oranges as far as I am concerned.
My round edge kit plays and tunes nothing like any of my modern sharp edge kits.
It doesn't matter what type of head that I use, The round edge kit is much different than the sharp edge kits.
 
The one that shows round 45, has about half as much edge touching the head as the full round and less than the 45 by itself. Don't try to make it difficult because it's not.
If you look at the photo taken in the same group, showing the drum with many plies, at the one that says 45 degree bearing and look at the dotted lines you can see how much touches the head.
It only takes a few of the plies to make a difference. Consider how thin drum shells are are it makes sense.
 
I have to agree with keep it simple

"the angle has very little to do with the edge itself, it's more of a crude measure of sharpness & an indication of the contact footprint under oscillation. Far more critical is the radius of the contact point itself."

The 'R' designations are where the center of the edge contacts the drum head in relation to the heads edge/hoop.

Not the angle of the cuts, but where those angles put the center of the bearing edge in relation to the center of the shell's plys determines where contact on the head is made, this along with the radius of the contact area (amount of wood contacting shell) have the greatest effect on sound.
 
The one that shows round 45, has about half as much edge touching the head as the full round and less than the 45 by itself. Don't try to make it difficult because it's not.

If you look at the photo taken in the same group, showing the drum with many plies, at the one that says 45 degree bearing and look at the dotted lines you can see how much touches the head.

Yeah, so one edge is sharper (is cut to a finer sharp edge, where the shell meets the head) than the other. Or, on the contrary, one edge is "rounder" (the head has more contact with the shell due to a flatter edge profile) than the other.

Don't try to make it difficult because it's not.

No, really, it's NOT difficult. I was originally questioning THIS comment made earlier about "hybrid edge profiles":

There are hybrid edge profiles that offer both a sharper edge for sustain, plus extra head contact through the washout.

How does an edge have a sharp edge (read: a very fine point of contact) AND "extra head contact" (which I read to mean a broader surface of contact) at the same time?!?!? I just want some clarification on this, because the idea intrigues me deeply...
 
Not the angle of the cuts, but where those angles put the center of the bearing edge in relation to the center of the shell's plys determines where contact on the head is made, this along with the radius of the contact area (amount of wood contacting shell) have the greatest effect on sound.

Well, perhaps if a sharp edge were cut with a 2º angle, the head would vibrate and come in contact with more surface of the shell, transferring the vibration/energy to the shell, and when the vibrations die down enough, the sharp edge would allow for the head to sustain freely. THAT'S an idea I've had for a long time, wondering if it would work. I'm wondering if K.I.S.'s "hybrid edge" idea has anything to do with it...
 
Are you referring to the round-over by chance? I'm not quite following...
Quite possibly Caddy. Maybe I'm suffering from terminology misunderstanding. Looking up "round over" now.

Don't try to make it difficult because it's not.
There's no way I'm trying to make this difficult. Why would I? I'm simply struggling to get my point across without the benefit of sketches/diagrams. The edge pictures you posted are very useful, but don't feature the form I'm talking about. Extracting snippets from your picture post; The counter cut has a form as the diagram showing a 90 degree interface (in red) on a fully resolved radius (in brown). The relief cut is a straight flat 45 degree, & the intersection is a very sharp R1 or less.

Well, perhaps if a sharp edge were cut with a 2º angle, the head would vibrate and come in contact with more surface of the shell, transferring the vibration/energy to the shell, and when the vibrations die down enough, the sharp edge would allow for the head to sustain freely. THAT'S an idea I've had for a long time, wondering if it would work. I'm wondering if K.I.S.'s "hybrid edge" idea has anything to do with it...
A lot to do with the principal, yes. The 2 degree angle is effectively created by the top of the full radius counter cut.

In hindsight, maybe my use of the term "hybrid" raised expectations of something groundbreaking. I was merely trying to say that there's more choice out there than sharp at one end of the spectrum, & rounded at the other. A combination of rounded & sharp forms are increasingly being used by those builders experimenting with head control. I've built up a lot of trial & error info on this subject as part of my "out there" kit project with Dean of Guru Drumworks, but I'll be damned if I'm going into detail on it here. I don't want to make things seem complicated.
 
See what you've done Soupy!

At the end of the day, if you are talking to custom builders like Guru, ask their advice for the sound you want to achieve. The custom builders are very good at translating the sound in your head to a specification for your drums.

Davo
 
See what you've done Soupy!
Davo
Nah, all's good Davo.

Back to the OP question, I'd always take the opportunity to use bearing edges as the primary means to shape head behaviour. Of course, if you've already got your drums, you've little choice (other than a re cut) but to use head selection to achieve your optimum sound. There's such a huge selection of head forms these days, you really can do almost anything. The only thing I have against using head based muffling, is that in all cases, it takes something away from the sound palate. Compared to a wide open head, they never add anything. It's a filtering exercise rather than a shaping exercise.
 
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