I was really in to Supercollider a long time ago, and I remember there were synths floating around on the mailing list that included big arrays of weird looking values, and they somehow made drum sounds. My brain is remembering that they were called eigenvalues, but I tried searching and didn't find much.
No idea how someone figured out or calculated the values. I think they were impractical to calculate at runtime in supercollider.
About Drums: the physics of overtones
21–30 of 31 posts
Re: About Drums: the physics of overtones
#22It's a great article, but the piano tuner in me must correct a detail about "typical musical instruments" such as pianos. The overtones are not necessarily perfect multiples of the base waveform and this is called inharmonicity. In fact, this is part of why a piano sounds like a piano and guitar sounds like a guitar. For any piano and especially the upright, the bass strings are actually too short to produce any vibr…
> In fact, this is part of why a piano sounds like a piano and guitar sounds like a guitar. My understanding is that it is a bit more complex than that, literally! The the final waveform is a not just W = sum(a_i * f_i) = Psi where a_i is the amplitude and f_i are the fundamental frequencies. It is actually W = sum(a_i * f_i + sqrt(-1) * (b_i * f_i)) = Psi + i * Phi Loosely, the imaginary part plays a significant rol…
That is way too simplistic as well, as this model is time invariant. Most instruments, due to physical nature of excitation, are variable in both frequencies and phases over time.
It is the main reason why modelling physically is the best way for realistic results right now - lossy lumped finite element models typically - digital waveguides are one of such models.
In such a model you can incorporate nonlinear damping and resonance functions over time at desired accuracy.
Re: About Drums: the physics of overtones
#23It's a great article, but the piano tuner in me must correct a detail about "typical musical instruments" such as pianos. The overtones are not necessarily perfect multiples of the base waveform and this is called inharmonicity. In fact, this is part of why a piano sounds like a piano and guitar sounds like a guitar. For any piano and especially the upright, the bass strings are actually too short to produce any vibr…
Any piano can produce the main frequency of the bass notes. Apart from length, the tension and density of the string play a role in the main frequency as well. The problem with shorter strings is rather simple. Shorter strings are stiffer than their longer equivalents. These strings produce sharp overtones, since there is less length of the string to vibrate on higher frequencies. Perfect overtones need perfect flexi…
Good to know, can't remember where I read that.
Re: About Drums: the physics of overtones
#24Earlier quoted context omitted.
Cheaper solution would be to try the open source Pd (PureData) in combination with the free "Programming Electronic Music in Pd" book [1]. [1] http://www.pd-tutorial.com/english/index.html
Or SuperCollider or any demo of a standard synth plugin dropped into a free VST host (like dropping a demo version of Massive [0] into Reaper [1]... though Reaper technically not free). [0] https://www.native-instruments.com/en/products/komplete/synt... [1] http://www.reaper.fm/
Don't forget http://overtone.github.io for (live) coding your synths, filters and effects!
Re: About Drums: the physics of overtones
#25One item on my TO-DO list is hooking up an electric guitar to an oscilloscope and frequency analyzer and do a video and/or blog post about the applied physics of heavy metal guitar sound.
There are tons of tricks employed in guitar playing to create interesting sounds by manipulating harmonics, by both the guitarist and the effect and amplifier signal chain.
Most guitarists that use these tricks are completely unaware of the physical phenomena involved. And the non-guitarist physics geeks always enjoy when I give a short demo with lots of distortion and artificial and natural harmonics tricks.
Re: About Drums: the physics of overtones
#26It's a great article, but the piano tuner in me must correct a detail about "typical musical instruments" such as pianos. The overtones are not necessarily perfect multiples of the base waveform and this is called inharmonicity. In fact, this is part of why a piano sounds like a piano and guitar sounds like a guitar. For any piano and especially the upright, the bass strings are actually too short to produce any vibr…
As a piano player you might find this guy interesting, https://en.wikipedia.org/wiki/Lubomyr_Melnyk
His playing style focuses nearly exclusively in using harmonics and resonance to create his music.
Re: About Drums: the physics of overtones
#27It's a great article, but the piano tuner in me must correct a detail about "typical musical instruments" such as pianos. The overtones are not necessarily perfect multiples of the base waveform and this is called inharmonicity. In fact, this is part of why a piano sounds like a piano and guitar sounds like a guitar. For any piano and especially the upright, the bass strings are actually too short to produce any vibr…
>For any piano and especially the upright, the bass strings are actually too short to produce any vibration of the main frequency,
Not sure what you're talking about here. For example, the lowest guitar string is an E2 which is 82.4Hz. If you calculate[1] the wavelength, it is 13.7 ft. The string lengths from bridge to nut[2] are only ~25 inches long and yet it's reproducing the fundamental of 82.4Hz without requiring the brain to fill in the gap.
I think that misunderstanding is similar to believing that a speaker can't reproduce 82.4Hz because the cone is not 13.7 feet in diameter, or you can't hear an E2 in a small room because the width and height of the walls is less than 13 feet. If this were true, when you listen on earphones, all 88 keys of a piano and entire range of guitar and vocals would be "audio illusions" of the fundamental frequencies since the physical sizes of the transducers and ear cavity are all less than 1 inch. The highest 88th key on piano is a C8 with a wavlength of 3.2 inches.
[1] http://www.mcsquared.com/wavelength.htm
[2] https://www.guitarlessonworld.com/lessons/parts-guitar-learn...
Re: About Drums: the physics of overtones
#28One item on my TO-DO list is hooking up an electric guitar to an oscilloscope and frequency analyzer and do a video and/or blog post about the applied physics of heavy metal guitar sound. There are tons of tricks employed in guitar playing to create interesting sounds by manipulating harmonics, by both the guitarist and the effect and amplifier signal chain. Most guitarists that use these tricks are completely unawar…
I'd look forward to seeing that - I teach music tech and having done that with a class singing a note and seeing the different harmonics in each person's voice is interesting, and seeing that applied to a heavy guitar sound would be interesting - as you say, there's lots that players do that they don't realise they are doing, and it will also give an understanding of what's possible to those who would then take that on board and use the techniques uncovered by it.
Re: About Drums: the physics of overtones
#29It's a great article, but the piano tuner in me must correct a detail about "typical musical instruments" such as pianos. The overtones are not necessarily perfect multiples of the base waveform and this is called inharmonicity. In fact, this is part of why a piano sounds like a piano and guitar sounds like a guitar. For any piano and especially the upright, the bass strings are actually too short to produce any vibr…
> In fact, this is part of why a piano sounds like a piano and guitar sounds like a guitar. My understanding is that it is a bit more complex than that, literally! The the final waveform is a not just W = sum(a_i * f_i) = Psi where a_i is the amplitude and f_i are the fundamental frequencies. It is actually W = sum(a_i * f_i + sqrt(-1) * (b_i * f_i)) = Psi + i * Phi Loosely, the imaginary part plays a significant rol…
I have a terrible maths background, so that's -way- above me.
However, I have a good grasp of why instruments sound like they do, so I'm hoping that your statement is a complex way (no pun intended) of showing that the waveform has many harmonics, and that those harmonics vary over time? Not looking for any kind of argument, just hoping for a bit of explanation of the above; From what I've learned over the years it's the balance of harmonics and the way that they change over time that gives an instrument its timbre and explains the difference in tone between instruments despite them playing nominally the same note (i.e. fundamental at the same frequency).
Re: About Drums: the physics of overtones
#30One item on my TO-DO list is hooking up an electric guitar to an oscilloscope and frequency analyzer and do a video and/or blog post about the applied physics of heavy metal guitar sound. There are tons of tricks employed in guitar playing to create interesting sounds by manipulating harmonics, by both the guitarist and the effect and amplifier signal chain. Most guitarists that use these tricks are completely unawar…
Yes lots of tricks. Picking/strumming close to the bridge versus at the middle. Pinched harmonics. Strumming past the nut. Natural harmonics at nodes of overtones. Exciting the strings by hitting body instead of strings.