Number of loops for best sound?

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Re: How To Fix Bearing Edge

Postby djembefeeling » Sun Jun 25, 2017 2:08 am

If it is a perceptional bias, we suffer from the same ;) Regarding the friction lock of the verticals, I think that is stronger than the theoretical effect of minute movement from vibration to even out all verticals around the drum. It would be easy to put the proof in the pudding by marking the verticals...

But if it isn't that, what is it? I was thinking till now that the effect rather comes from the constant beating of the skin and perhaps the soundvibration in the skin, that it has some effect on the homogeneity of the skin. I know you don't buy that, we had that before. But I still think that hitting the skin may perhaps result in a more homogenous distribution of tension within the skin, and not due to a homogenous distribution of the tension of the verticals. Isn't it true that a skin needs less beating for a good tune when you full the skin until it's soft?

Still it is a question why the skin is not tuned well when you are generous with diamonds...
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Re: How To Fix Bearing Edge

Postby boromir76 » Sun Jun 25, 2017 7:37 am

michi wrote:In theory, with a drum without flips (except the one or two to lock the rope), while playing the drum, the vibration can allow the verticals to minutely slip over the bottom and top loops. That should eventually even out the tension all around. Once the verticals are flipped, they are definitely locked in place and there won't be any more movement across adjacent verticals.
Michi.

This reminded me on the colapsing bridge phenomena, where the poorly constructed bridge colapses because of some gales which forces it into resonance. Eventually the resonance becomes so strong that it weakens bridge structure with devastating effect. Maybe there could be some kind of analogy with milder effects also with skin, drum and verticals. Note striking similarity between bridge and djembe in video bellow (verticals :-))
https://www.youtube.com/watch?v=nFzu6CNtqec
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Re: How To Fix Bearing Edge

Postby michi » Sun Jun 25, 2017 8:56 am

I don't have a scientific explanation. But I'm pretty sure that, after a fitting a new skin, it helps to play the drum for a while and to tune it up slowly, playing some more in between tunings. I suspect that the vibration does help for everything to "settle in". The rope will stretch a little bit more, the skin will stretch a bit more, the rings settle a bit more, etc…

Eventually, things are all in their right place and have found some sort of balance, and then tuning is more effective to bring out the voice of the drum. Sounds all very "new age-ish", I know, but it seems to work.

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Re: How To Fix Bearing Edge

Postby drtom » Sun Jun 25, 2017 4:05 pm

michi and I seem to be on the same page regarding the "settle in" issue.

I have not taken careful measurements and will probably never conduct rigorous reproducible experiments. My opinion is based on my (probably incomplete) understanding of the tuning system. I know each of its parts very well and how they relate to each other. My imagination and common sense enable me to extrapolate (sometimes with confidence, other times not so much).

That's what I tossed out here. Please do correct me when I'm wrong.

Even if I were to take measurements, the results would probably be minute. The rope may or may not slip its friction lock. Instead, perhaps, more of the stress is shifted to that point of the system. Perhaps it's a combination of slip and shift. Can't say for sure.
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Re: How To Fix Bearing Edge

Postby boromir76 » Mon Jun 26, 2017 10:28 pm

One thing is very clear here: nothing is clear. :giggle:

I would not contribute this to one or two, but all possible factors which could have potential effect on sound. Playing the skin while being tuned up, can not be dissmised as negligible in my opinnion. There are not just few, but thousands and thousands of punches in case of slow tuning and playing aproach. If skin can be presoftened with few simple thrashes at something concrete, I don't see any reason why something like this would not have any effect at all on skin latter, while being played and tuned.
Can be skin acoustically completely the same if someone plays on it for one month, slowly delivers hundreds of Newtons of force into it with punching and tunes it up slowly, or if he just cranks it up to the same pitch in one or two days after it dries without any playing? I doubt it. Here is why. I have once put very thick cow skin on dundun. The skin had at least 5mm of thickness. The drum sounded literally like plastic bucket at first, but with the time and playing, the skin has visibly soften up in the centre and the sound also became nice and mellow. It is safe to say that the shifting and sliding of the skin and verticals had possibly very litlle to do with it as it is low tuned drum. I know the mechanics and force projections of playing the duns and djembe are different etc. but nonetheless, the playing has had its important effect on sound.
Maybe playing has two not just one functions in changing sound. Maybe it evens the tension across the head (from various possible reasons discussed) and it also changes the properties of the skin. The result could be the sum of all this factors..
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Re: How To Fix Bearing Edge

Postby djembefeeling » Mon Jun 26, 2017 11:12 pm

And I thought the discussion hit a dead end. Fortunately, it didn't. :D

Still my main concern is how to apply the most even pull to the skin if this really is what makes the djembe I got from this guy so extraordinary. We all agree, it seems, that a djembe evens out with time. But I doubt it completely evens out. You can hear that from plucking the rope of the verticals one by one. They do not sound completely the same, even after things settled in. Perhaps the kind of stand which pushes down the rings with entirely even force would help? Maybe a new level of quality could be reached.

boromir76 wrote:Can skin acoustically be completely the same if someone plays on it for one month, slowly delivers hundreds of Newtons of force into it with punching and tunes it up slowly, or if he just cranks it up to the same pitch in one or two days after it dries without any playing? I doubt it.

Everyone does. But the effect that Michi started to describe is rather that there is a difference when you first beat the skin for a good deal and then put more diamonds in than vice versa. When you first crank it up with diamonds and then beat the shit out of your djembe, the result shoud theoretically be the same, but for some reason it seems it isn't. After cranking up, playing does not seem to improve the sound as much as before. But this could still be perceptional bias.

boromir76 wrote:Here is why. I have once put very thick cow skin on dundun. The skin had at least 5mm of thickness. The drum sounded literally like plastic bucket at first, but with the time and playing, the skin has visibly soften up in the centre and the sound also became nice and mellow. It is safe to say that the shifting and sliding of the skin and verticals had possibly very litlle to do with it as it is low tuned drum.

That is a good example of skin softening and tuning from beating. Cow is different from goat, but I think the effect is still the same.

boromir76 wrote:One thing is very clear here: nothing is clear. :giggle:

That is true. The discussion is making me really curious. I think I will experiment a bit to put my beliefs about djembes to the test. If anyone will join, that would give more substantial results.
Last edited by djembefeeling on Mon Jun 26, 2017 11:37 pm, edited 1 time in total.
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Re: How To Fix Bearing Edge

Postby boromir76 » Mon Jun 26, 2017 11:31 pm

But the effect that Michi started to describe is rather that there is a difference when you first beat the skin for a good deal of and then put more diamonds in than vice versa. When you first crank it up with diamonds and then beat the shit out of your djembe, the result shoud theoretically be the same, but for some reason it seems it isn't. After cranking up, playing does not seem to improve the sound as much as before.

But if you beat the skin while playing and than tune it, how can this be the same as only cranking it up and than playing? The skin gets moisture, it maybe also softens a litlle during slow process of tuning and it can not behave the same.
There is theoreticall difference also concerning stress under which the skin gets. :uglynerd: The skin in first scenario is constantly (depending on drummer) moisturized from hands and than dried up, than tensioned again, and than played again, dried up, tensioned, etc. Theorethicaly, the skin is under more stress (stretching, contracting, tensioning,..), than with only cranking up to the danger zone and than playing. In other words, would it be possible that with slow aproach the skin settles better also because of that?
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Re: How To Fix Bearing Edge

Postby djembefeeling » Mon Jun 26, 2017 11:55 pm

I am not sure about moisturizing from your hands. After all, that would mean that only the parts of the skin that you actually touch would have the extra stress you described. I guess the moisture in the air is more important.
But the thought that the slow and alternate process of stretching and contracting has different results than one enormous stretch and then a long period of contraction in the material is plausible. Like slow cooking and fast cooking makes a big difference in the consistency and taste of food. Only in that example it is a chemical process, in the skin it is a physical process, I'd say.

BTW, for the sound of dunduns, it should also help to soften and tune the skin when you submit it to direct sunlight, I was told.
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Re: How To Fix Bearing Edge

Postby boromir76 » Tue Jun 27, 2017 12:15 am

djembefeeling wrote:I am not sure about moisturizing from your hands. After all, that would mean that only the parts of the skin that you actually touch would have the extra stress you described. I guess the moisture in the air is more important.

Ofcourse it is not whole surface which gets moisture from hands, but maybe it helps to "mold it in" and stretch just a litlle bit different or better with beating the skin while the drum gets slowly tuned... There is moisture in the air but can be very relative and possible in some conditions negligable compared with sweatig hands, where mosture is aplied with direct contact. From my eksperiences, the amount of sweat from hands, when playing in hot continental summer day can top air moisture easyli, resulting in skin break just where the hands lay on drum edge surface. Been there done that. ;)
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Re: How To Fix Bearing Edge

Postby djembefeeling » Tue Jun 27, 2017 8:19 am

If what you say is true it would be important to play the drum from different sides before you stretch it any further so as to apply the moisture as even as possible. What about moisture in dunduns? If it is so important for softening the much thinner goat skin, shouldn't we need to moisturize the much thicker cow skin, too? It doesn't seem to be necessary, though. But I admit that cow skins on dunduns need much more time to soften and tune in...
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Re: How To Fix Bearing Edge

Postby boromir76 » Tue Jun 27, 2017 11:12 am

My speculation is that excessive hand moist together with playing changes the skin differently with both tuning aproaches, although they both seem the same in principle, just processes take litlle different order.
The fact that whole playing surface does not get even treat with playing is true, but that does not mean it could not make any difference towards better sounding drum with longer tuning treatment. At this point the question that comes into my mind opens up new provocative dillema: Is even treatment of the skin in this sense best for achieving good sound? What if this uneven wear of the skin makes something to the sound? I know, I have gone far out into the open with this. :-D
The dunduns are played almost exclusively in the center of the skin, with sticks and the force of the punch is therefore projected into much smaller area, making greater effect when softening the skin. The principle of tuning the dunduns is not the same as with djembe. I don't know if this two different concepts of tuning are even relevant and used with duns.
I would not go as far, to say only playing makes huge difference, but the combination of playing the skin, moistirizing the skin, possible vertical slipping etc. make different sound.... probably. Or maybe it is only perceptional bias as you mentioned before.
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Re: How To Fix Bearing Edge

Postby korman » Tue Jun 27, 2017 12:25 pm

My 2 cents:)

I often use a rubber hammer when tuning the drum. Beating the rim with the hammer (especially on the opposing side from diamonds) helps the skin settle and maybe a bit simulates the effect of playing.

Skin treatment changes the sound, obviously. For example, when hearing my dunduns Daniel suggested I rub the skins with oil and in the course of two workshop days it did lessen the overtones (hard sound).
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Re: How To Fix Bearing Edge

Postby djembefeeling » Tue Jun 27, 2017 9:40 pm

korman wrote:I often use a rubber hammer when tuning the drum. Beating the rim with the hammer (especially on the opposing side from diamonds) helps the skin settle and maybe a bit simulates the effect of playing.

What do you mean by beating the rim? Is it the ring that you beat or the skin near the rim? If you just beat the ring, you just tune. That wouldn't simulate the effect of playing. If you beat the skin with a rubber hammer that would be something new to me...

korman wrote:For example, when hearing my dunduns Daniel suggested I rub the skins with oil and in the course of two workshop days it did lessen the overtones

Yes, that's a good example of cow skin treatment. The oil is permanently moisturizing the skin and softening is massively cutting short the process.
I never used oil on my duns, though. I once did buy a set of duns back from a customer after a couple of years. The skins were treated with oil and didn't sound good, but somehow mushy. I did lots of ironing with blotter paperto get as much oil of the skins as I could. Then they did sound much better. I think those skins had been drowned in oil.

boromir76 wrote: Is even treatment of the skin in this sense best for achieving good sound? What if this uneven wear of the skin makes something to the sound?

Interesting question. The skin usually isn't entirely even. The spine is thicker than the out regions. So perhaps what it needs is an unenven pull? But that would be impossible to find out without intense measurements done in a modern laboratory of physicists.

I think I still go for the even pull, since that is what I was told is one of the secrets that made this drum so extraordinary. About that moisturizing with hand sweat I am still not sure if that does anything. When the humidity in the air is high, djembes do sound sort of dull. I think I am not much of a hand sweater since I could never experience the skin being sort of humid after I played it for some time.
In Africa I did sweat like hell during the lessons. The sweat was dripping from my head on the drum as if I had opened the tap. That didn't result in a skin break. But since the fine read dust sat on the skin, I pounded this dust into its fabric. After many weeks of practice, it looked fabulously redish but didn't sound good any more.

Perhaps what is more important in playing the skin with your hand for better tuning is - much like korman said about the dunduns - the fat of your hands rather than the sweat. The fat stays in the skin and is punshed into the fabric. Playing from all sides results in better tuning is my best guess.
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Re: How To Fix Bearing Edge

Postby boromir76 » Wed Jun 28, 2017 6:21 am

Even pull is probably best for getting good sound results, but what happends with the skin with wear and how playing affects the hide and sound is probably another story.
Djembe is so specific drum, that even if one had resources to test different tuning aproaches and playing conditions, it would be very hard if not impossible, as there is no identical hand crafted drums and skins to be tested under different conditions. It would probably take industrial crafted shells. But how to get identical skins? I don't see any way how to get two completely identical hides. One way would be to use plastic ones as substitudes, but that aproach would not consider the effects of playing on the skin or possible changes with different tuning aproaches.
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Re: How To Fix Bearing Edge

Postby drtom » Thu Jun 29, 2017 3:14 pm

djembefeeling wrote:But I doubt it completely evens out. You can hear that from plucking the rope of the verticals one by one. They do not sound completely the same, even after things settled in.


Great observation. :clap: I often check how tightly a skin is pulled by the pitch of the rope. But . . .

The verticals will invariably be of irregular length (this affects the pitch) due to various reasons. The loops are irregular, the rings are not level, she shell is not level . . .

In fact, the only way to tune the verts to the same pitch would be to vary the tension.
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