Kalimba tines: Modifying the overtones
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- เผยแพร่เมื่อ 20 ส.ค. 2024
- Some experiments and explanation about the overtones of a kalimba tine, and how they can be modified to get a clearer, more useful sound.
Check out the follow-up where I show some complete kalimbas with overtone tuning: • Overtone Kalimbas - 3 ...
I was going to make my own supplement video to explain tine overtones but this video perfectly sums up the information. Thank you for this!
This is a wonderful real life experiment on overtones, and you did it without hurting my brain, thank you :)
This is such a fascinating and succinct video. Thank you for making it!
Finally! This is exactly the information I was looking for, thank you!
Thank you so much! It's the most informative video on the subject, helps a lot.
Great. This video is a kind of science work. Perfect.
Really useful information, thank you!
brilliant stuff~ thanks for sharing your work!
Thanks! Don't miss part 2 where I showed 3 complete overtone tuned kalimbas
I guess this also can be achieved by tuning the tines like they do in accordion reeds, by filing the base or the tip of the tine, removing weight from these parts and lowering or rising the tone accordingly.
Tines change pitch by 12 equal semitones if they change length by the 24th root of two not from their tips but from their width PAST their tip. If a tine is 4 inches long and 1/8 inch wide its length should be considered as if it were 4 inches plus 1/8 inch long, a tine that is to be a semitone higher in pitch will need to be shorter than 4 1/8 inches which length must be divided by the 24th root of two and have 1/8th of an inch subtracted from it to arrive at the new length. Each tine will be positioned 1/8th of an inch shorter than its calculated length. The octave is at the square root of two but only if we calculate as if the tines are each 1/8th" longer than they actually are.
I suspect the harmonic structure of tines is " 2, 13 and 35 " (no fundamental at all) which we hear as 1, 6.5 and 17.5., like thirds of tones and quarter tones, inharmonic partials.
Bending the tine flattens the 13 and 35 until they become 12 and 34 and so we hear "2, 12, 34" which is the same as the upper octave of "1, 6, 17.". If "1" is C1 then "6" is G3 and 17 is C#5, an unusual chord, a fifth above the 1, a semitone above the 1 and a tritone between the 6 and 17. the "6" makes the highs sweet sounding but the lows bring in more of the the 17 which sounds spooky and otherworldly
Very interesting, Bill! In practise, I still do the fine tuning by ear, but I will experiment with the added width of the tine as you wrote.
Not sure if the harmonic structure of tines depends on any sort of integer relationship at all, as it does with (ideal) strings. Still, curious if the 2nd harmonic (normally at 17.something) can be brought down enough to add usefully to the overall sound.
It does seem not exactly integer, but I'd like it considered as a possibility since organ pipes woodwinds reeds and wound strings are pretty far from integral also, and more so as their harmonics go up.
The tine might also have a tendency towards integers even if further astray which would seem all the less present if the fundamental were missing. When I had some acquaintances run a top of the line spectral analyzer on the array mbira tine they were convinced in advance that the tine could have nothing at all like a harmonic structure, but they did not consider a missing fundamental. The images revealed a lot of very brief energy one octave below the fundamental much to their surprise.
I think your figures on the partials of a tine are accurate, but the deviation from harmonic relation is not anywhere near as great if we treat the actual fundamental as the 2nd harmonic, 2, 13, 35 comes pretty close to a tines partials.
On the array mbira the tines are bent until we get a perfect "6", then the "17" is often just a little flat from 12 equal indicating that for us to bend the tine enough to get a perfect 12 equal 6 we end up bending the 17 a little too much, being higher its probably more reactive to the bend.
I would say a tine is 1/2 a string, If we look at the node diagrams we can see the tine is even moving like 1/2 a string although slightly distorted, a string changes by powers of 2 for octaves but a tine changes by powers of the square root of 2 which is geometrically "half" a string in terms of math too then.
This means a tine might be considered only half of a DIMENSION, it is a line with only 1 point of contact and a string is a whole dimension, a line with two points of contact (which allows stretch tension to play a role). Partial dimensions are what FRACTALS are made of, perhaps tines are more fractal musically than strings.
Tine instruments include accordions, harmonicas, mbiras, kalimbas, closed organ pipes (a tine of air) music boxes, reeds such as clarinets oboes saxes and bassoons and some woodwinds such as the pan pipe and ocorina. These instruments tend to have pretty dynamic sound, it seems kind of fractal, especially in air blown reed instruments
I like the idea of a tine having half the dimension of a string, and have to ponder the implications a bit. Now, is there a way to give tines some more harmonic padding in the overtone area of an octave, octave + a 5th, and 2 octaves?
My tines are 1/8thwide and not too thick, all the other dimensions did not seem to work as well, wider and the harmonic structure changes a little for the worse (more "plink" less mmmm), narrower and you have a weak sound, thicker it hurts to play, thinner and the tine bends too easily to be stable. I find tines to be more fussy than strings, they are sonic princesses, but in return they don't go out of tune easily like strings and don't need as big or elaborate a chassis that need handle undue tension and splay the strings so they can be played smoothly in any key, something the harp can not do without elaborate pedals or levers, about $20.000 for a good one.
I'd need a spectral analyzer to see how dimension might be manipulated to control or bring in specific harmonic structure, but wider thinner tines sound very different. To my ear the best wide tines come to a near knife edge, those rare thin tine kalimbas sound amazing to me, glass like, super clear, but such wide tines could never be used in large numbers. I'd love to try those experiments. and also see if a synthesized timbre of 2, 13, 35 does sound like a tine, or does it sound "off"?
I've built some four octave weighted tine metronomes with 120 heavily weighted tines tuned to tempos which feature octaves -1, -2, -3, -4. and which can play any composition as a combination of tempos rather than tones.
Chords, melodies, everything translated into tempos so its possible to play as many as 40 tempos at once. The tempos of the tines, after they are weighted at the tips by a large bolt, increase by 12 equal semitones but here is the weird thing, there are upper harmonic tones that the weighting throws into an unexpected result, instead of the tones increasing by 12 equal semitones its more like 36 equal!!
So if the weighted tines are tuned to 12 equal in terms of tempo the tones will be in approximately 36 equal....say what? This indicates some very sophisticated sonic interactions for tines, that seems like a FRACTAL effect where one kind of simple order leads to another transitional and very unexpected kind of more sophisticated order so I'd think it might be possible to further manipulate tine timbre as you suggest and with a spectral analyzer as guide small dimensional changes can be controlled to have very large fractal effects.
love this video make more
Wow, that's really fascinating information! I wish I had known this when I was trying to build some kalimbas a few years ago.
While watching the video, I was wondering if the same principles apply to wooden tongue drums and xylophones (or more generally, wooden idophones) as well. Any thoughts on that?
Wood tongue drums: Yes (although bending will be difficult). Xylophones: Not really; those are free bar instruments, that have a different overtone structure, but which also can be tuned. There's a section in Bart Hopkin's book about those too.
Wow amazing information! Now I understand why the last 3 tines on my c 21 key kalimba sound soooo bad to me! ( my low f natural is also putting out a nasty C sharp! ) I would love to play with your weighted method what did you use as a weight on your tines? Honestly any advice would be amazing!
a small bolt & nut (with washers) could already work. Just clamp it to the edge and hear if it makes any effect
Hi, I have read both Music Instrument design and Making Lamelllaphones by Bart Hopkin, in the later book, he described a different method of lowering the 2nd mode which is thinning at 1/5 from the end of the tine, as opposed to thinning at the midway point. From my limited experiments, a regular shaped tine with 2nd overtone at 1octave + minor 6th will need to remove about half of its thickness at 1/5 position to lower the 2nd mode to 1octave + perfect 5th, so how do you find this method as compared to thinning at the middle?
The best way to bring the overtone into a 4:1 ratio with the fundamental is to add a drop of rosin core solder to the end of the tine. Put a generous drop on the end, then file it back until it's exactly in tune. I did that when I made my kalimbas. It's much more effective than what this video describes. His are just random alterations. The side benefit of adding solder is that it lowers the fundamental more than the overtone, so the tines are shorter.
@@prentrodgers Thank you!
How do you make your kalimba tines?
I cut them from strips of spring-tempered steel, shape the tip by grinding, then smooth the edges on my belt sander
@@tonginstruments I have stainless steel which is too soft and bends easily, how can I turn the steel into kalimba tines?
@@Baklavakhamu you need to get steel for springs, it is much harder. As an alternative, you can use old sawblades and take of the teeth (lot of work!)
@@tonginstruments thanks a lot!!
Interesting observations.
But part of the charm of the sound of a lamellophone like the kalimba is that it has non-harmonic overtones. Bringing them into the harmonic series reduces everything to the bland sound of something like a Rhodes electric piano. If that's the sound you want, why not just use a Rhodes, and save yourself a lot of filing and bending?
I would not consider a Rhodes piano to have a bland sound, and would be even proud of the comparison...
As I replied to another comment, the point is not to dismiss traditional lamellophones, but to explore new timbres and musical potentials.
The only instruments with accurate harmonics are sirens and stable electronic oscillators which would suggest perfect harmonics result in a sterile sound that is to be avoided for most music!
The brain tunes out redundant information, if harmonics are perfectly predictable there is no reason to pay attention. The fact is people tend to most love the instruments which can be made to go furthest from harmonic perfection and not the instruments which are more harmonically perfect.
The piano is harmonically "off" with all the string winding and hammer muting, the harpsichord is more true with its thin plucked strings but it is not preferred. The voice can get very inharmonic tones and most singing styles employ some of these tones, especially at the most passionate moments in the music.
Electric guitar harmonics are off (windings and magnets) and amplifier intermodulation complicates the issue still further, people love it.
Harmonic purity of tone is really only valuable for instruments expected to play complex harmonies, but most instruments are not polyphonic, they are monophonic and the inharmonic partials allow monophonic instruments to sound like they are producing chords which is good, but you don't want prexistant chords in an instrument expected to play large scale harmony like this:
th-cam.com/video/fA3H5yjFU3M/w-d-xo.html
The rhodes-like sound is what I'm after in a modern kalimba. I have nothing against the traditional sound with non-harmonic overtones, but I have no use for it. With small kalimbas I make I never ran into the issue of overtones being off, but now I'm building a big one with a piano layout and overtones are an issue.
But why? Why is a "clearer" sound more useful? Why turning a unique sound into a 'correct' sound?
Well, when the fundamental tone is reinforced by its overtones, its pitch is recognized more easily and clearly. You can play more complex music then and it holds its place better when combined with other instruments. Of course doesn't mean there is anything wrong with the natural sound of kalimbas...
I understand what you mean. Still I think the uniqueness and distinctiveness of the instrument might be lost. However, lots of success with your intriguing journey!
objectively bad isnt the same as unique
VIDEO HAS GREAT INTENT, BUT POOR EXECUTION. If you have a thick accent and try to speak English, please slow down and try to enunciate. Please.