*Does anyone know of a way to build a Bode Frequency Shifter in Kyma?

• Does anyone know of a way to build a Bode Frequency Shifter in Kyma

*Does anyone know of a way to build a Bode Frequency Shifter in Kyma?

-- OlleRomo - 09 Jan 2005

* The what and wherefor of Kyma compressors...

-- DavidMcClain - 16 Nov 2004

• I want to generate a 22k5 waveform inside 44k1 samplingrate, which should result in an analog sine, right? But it is amplitude modulated with a period length of 49 samples. How come? And watching the oscilloscope this is relevant for all high frequencies from 500 Hz on already. Clearly visible amplitude modulation. Very curious. Why do I see amplitude modulation for frequencies near the half sample rate

-- MathisNitschke - 11 Oct 2004

* What is the relationship of a peak detector output to the input bandwidth?

-- DavidMcClain - 24 Feb 2004

• How does Kyma combine Newton and Hooke?

-- DavidKiers - 20 Feb 2004

• I hope this is the right place for this: I'm having troubles with things lingering in memory. For example when using the Memory Writer which is being fed by a Generic Source from disk, if I change the audio file that the Generic Source is pointing to, I sometimes get pieces of the old audio file spliced into the new audio file. Also, when I put a prompt in a field, such as "?rate", the first time I run the sound I get the prompt (as I want), but on subsequent plays I don't (the first value I entered is re-used). In both cases is there some way to clear out old data from memory and start with a blank slate each time I play a sound?

-- SimonAmarasingham - 08 Feb 2004

• I hope this is the right place for this: I'm having troubles with things lingering in memory. For example when using the Memory Writer which is being fed by a Generic Source from disk, if I change the audio file that the Generic Source is pointing to, I sometimes get pieces of the old audio file spliced into the new audio file. Also, when I put a prompt in a field, such as "?rate", the first time I run the sound I get the prompt (as I want), but on subsequent plays I don't (the first value I entered is re-used). In both cases is there some way to clear out old data from memory and start with a blank slate each time I play a sound?

-- SimonAmarasingham - 08 Feb 2004

• TowerOfBabel

-- KarlMousseau - 26 Oct 2003

• Can anybody explain a parabolic function to me? And what´s the difference between that and a sine wave?

-- MathisNitschke - 09 Jan 2004

• Does anyone know of a tool (or ideally, a way to do it in Kyma) that can search an .aiff for zero crossings and then build wavetables out each cycle, hopefully with the option to interpolate the cycles out to a fixed sample size?

• Does anyone know of a tool (or ideally, a way to do it in Kyma) that can search an .aiff for zero crossings and then build wavetables out each cycle, hopefully with the option to interpolate the cycles out to a fixed sample size?

Dispersive Media -- This is a medium in which waves of different frequencies travel at different velocities. With electromagnetic radiation (light, radio waves) this occurs because the index of refraction of the medium is frequency dependent. The index of refraction controls how much the wave bends away from a straight line as it traverses the medium. You all know about prisms and how it bends blue light more strongly than red light, hence casting a spectrum or rainbow of colors on a projection screen.

In the case of light the index of refraction is a property of the material. Many of you have seen the colored fringes outlining objects in cheap binoculars or telescopes. That chromatic aberration is caused by the fact that the index of refraction of the glass lenses is different for blue light than it is for red light. The speed of blue light through the glass differs from the speed of red light, and so they don't come to the same focus. In most glasses the index of refraction is larger at blue wavelengths than at red.

In the case of radio waves, those chirps referred to above happen because of the interaction of free electrons in the high stratosphere with our Earth's magnetic field. That "plasma" has an effective index of refraction that depends on the frequency of the radio waves, the strength of the magnetic field (which grows stronger toward the north and south magnetic poles), and the electron density. This is also the reason why radio waves of low enough frequency bend back toward Earth after radiating skyward from the transmitter, hence enabling the reception of short wave radio signals from the other side of the Earth.

But probably of more interest to the reader is the concept of dispersive acoustic media. A metal bar is a classic example of dispersive acoustic material. High audio frequencies travel at a different speed in the bar than lower audio frequencies, and this is what gives rise to the anharmonic spectra when the bar is struck with a mallet. The resonant frequencies of a bar are determined by the speed of sound, and since low and high frequencies travel with different speeds the resonant wavelengths do not bear a simple geometric relationship to one another. Most of our musical instruments are based on the creation of harmonic spectra, but metal bars and plates, and even the kettle drum, exhibit distinctly non-musical overtone series. But that's what makes them so fascinating to hear!

So why does this happen? We know that very fine strings are almost perfect (but not quite perfect) harmonic resonators. That's because the tension in the string is directly related to its displacement when plucked or bowed with a rosin coated horse-hair. But in metal bars and plates that restoring force is a nonlinear function of the displacement. The speed of sound in the metal bar varies according to the square root of the frequency, while it is constant in the ideal thin string. Hence high frequencies have a higher speed of propagation in the bar compared to lower frequencies.

[For those familiar with the subject, the wave equation for a thin string is a linear 2nd order differential equation, while for a metal bar or plate the equation is 4th order in spatial coordinates and 2nd order in time -- exceedingly difficult to solve except for the simplest boundary conditions.]

[Gee... I hope this is the appropriate way to answer questions on the Wiki?]

-- DavidMcClain - 19 Nov 2003

• Would a Klein bottle have a resonant frequency

• Would a Klein bottle have a resonant frequency?

Yes! As a surface in 3-space it is a single sheet with no front nor back, like a Moebius strip. But as a bottle, it contains a closed volume of space. Hence it could serve as a quarter wave resonator with one end closed. You can fill it with water without it leaking out.

-- DavidMcClain - 19 Nov 2003

Dispersive Media -- This is a medium in which waves of different frequencies travel at different velocities. With electromagnetic radiation (light, radio waves) this occurs because the index of refraction of the medium is frequency dependent. The index of refraction controls how much the wave bends away from a straight line as it traverses the medium. You all know about prisms and how it bends blue light more strongly than red light, hence casting a spectrum or rainbow of colors on a projection screen.

In the case of light the index of refraction is a property of the material. Many of you have seen the colored fringes outlining objects in cheap binoculars or telescopes. That chromatic aberration is caused by the fact that the index of refraction of the glass lenses is different for blue light than it is for red light. The speed of blue light through the glass differs from the speed of red light, and so they don't come to the same focus. In most glasses the index of refraction is larger at blue wavelengths than at red.

In the case of radio waves, those chirps referred to above happen because of the interaction of free electrons in the high stratosphere with our Earth's magnetic field. That "plasma" has an effective index of refraction that depends on the frequency of the radio waves, the strength of the magnetic field (which grows stronger toward the north and south magnetic poles), and the electron density. This is also the reason why radio waves of low enough frequency bend back toward Earth after radiating skyward from the transmitter, hence enabling the reception of short wave radio signals from the other side of the Earth.

But probably of more interest to the reader is the concept of dispersive acoustic media. A metal bar is a classic example of dispersive acoustic material. High audio frequencies travel at a different speed in the bar than lower audio frequencies, and this is what gives rise to the anharmonic spectra when the bar is struck with a mallet. The resonant frequencies of a bar are determined by the speed of sound, and since low and high frequencies travel with different speeds the resonant wavelengths do not bear a simple geometric relationship to one another. Most of our musical instruments are based on the creation of harmonic spectra, but metal bars and plates, and even the kettle drum, exhibit distinctly non-musical overtone series. But that's what makes them so fascinating to hear!

So why does this happen? We know that very fine strings are almost perfect (but not quite perfect) harmonic resonators. That's because the tension in the string is directly related to its displacement when plucked or bowed with a rosin coated horse-hair. But in metal bars and plates that restoring force is a nonlinear function of the displacement. The speed of sound in the metal bar varies according to the square root of the frequency, while it is constant in the ideal thin string. Hence high frequencies have a higher speed of propagation in the bar compared to lower frequencies.

[For those familiar with the subject, the wave equation for a thin string is a linear 2nd order differential equation, while for a metal bar or plate the equation is 4th order in spatial coordinates and 2nd order in time -- exceedingly difficult to solve except for the simplest boundary conditions.]

[Gee... I hope this is the appropriate way to answer questions on the Wiki?]

-- DavidMcClain - 19 Nov 2003

Yes! As a surface in 3-space it is a single sheet with no front nor back, like a Moebius strip. But as a bottle, it contains a closed volume of space. Hence it could serve as a quarter wave resonator with one end closed. You can fill it with water without it leaking out.

-- DavidMcClain - 19 Nov 2003

• This question came up during the course at CCMIX. We were analyzing a recording of lightning as captured by the Very Low Frequency radio receiver at NASA Marshall Space Flight Center in Huntsville Alabama. On their website, they explain the chirp and tweak effects as being the result of an impulse travelling long distances through a 'dispersive medium' through which high frequency waves travel faster than low frequency waves. Under what conditions would high frequency waves travel faster than low frequency waves? (In other words, what constitutes a 'dispersive medium' and how might one model it in Kyma?)

-- CarlaScaletti - 11 Oct 2003

• TowerOfBabel

-- KarlMousseau - 26 Oct 2003

• i am searching for ways to implement a StructureGenerator

• I am searching for ways to implement a StructureGenerator

• What is a Capybara?

-- KurtHebel - 18 Oct 2003

• i am searching for ways to implement a StructureGenerator

-- MichaelStrohmann - 17 Oct 2003

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• Would a Klein bottle have a resonant frequency

-- CarlaScaletti - 11 Oct 2003