On science meeting art, and travel-safe tablas

C.V. Raman did this work while he was an accounts officer in the British government, and that this work got him elected to the Royal Society.

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I have written in the past about Sir C.V. Raman’s work on understanding the Indian drums–the tabla and the mridangam–and their peculiarity at being percussive instruments that can achieve harmonic overtones. The secret is the black patch that is seen on every tabla or mridangam that makes the centre of the circular membrane denser than the periphery. In fact, CNR Rao points out that Raman did this work while he was an accounts officer in the British government, and that this work got him elected to the Royal Society.

This is all good. However, as the percussionist U. Sivaraman and Dr. T. Ramasami, Director of the Department of Science and Technology of the Govt. of India explained in the thirteenth ISRO-Satish Dhawan lecture at JNCASR on October 16th 2012, the materials that are traditionally used to make these drums do not satisfy phytosanitary constraints–island nations will not allow you to carry untreated leather without decontaminating it first. Fumigation effectively destroys the stuff that holds the black patch together — usually something like cooked rice.

The solution, then, is to use materials that reproduce the properties of traditionally used materials while meeting safety norms. Simple enough? Not even close: the traditional materials have been fine-tuned over millennia. And nobody knows exactly why the peculiar combinations of materials used in the making of these drums work.

The drum-heads have three layers, two of which are annuli. The layer that is entire is made of goat-skin. Goat skin from Bengal is preferred to goat-skin from Rajasthan. This layer also has the black patch on it. The black patch is iron oxide, silica and manganese held together by some adhesive. The silica and manganese are provided by river-bed sand. River-bed sand from Tanjore gives the drum a different sound quality compared to sand from Varanasi. The three layers are held together by ropes made from buffalo hide that tie the membrane down at exactly sixteen equally spaced points on circumference. The shells that these membranes are mounted on are made of particular types of wood–jackfruit tree wood is the best kind.

All of these things are necessary. Change any of them and the result is bad sound. Unless you know what each component does. U. Sivaraman and T. Ramasami have spent a decade looking for the answers.

The annular layers are there to cut out the highest frequencies, while still retaining up to nine overtones. This particular detail is actually due to CV Raman and a 1935 Indian Academy of Sciences paper.

Untanned goat-skin is used in the mridangam because it has the highest strength (per unit thickness). The annular layers are usually cow-skin.
Also, monitor-lizard skin is used in the kanjira, U. Sivaraman pointed out. But monitor-lizards are endangered, and we now use something else.

The shells are made of particular types of wood because these types of wood have the best sound radiation properties.

With modern materials, and Fourier analysis, Dr. Ramasami and company have managed to make novel versions of the Indian drums that reproduce the sound quality that connoisseurs enjoy, while also keeping the tabla travel-safe. This even includes reducing temperature-sensitivity letting musicians play in air-conditioned halls. They haven’t been able to make the drums humidity-resistant, though, which is an important shortcoming.

Friday Night Music — seriously good music

I have a Facebook friends list that posts some very cool music. It is apparently guitar season on my news feed; my ears aren’t complaining. I post the two that I liked best.

The first one is Joe Bonamassa playing BB King’s The Thrill is Gone. This is brilliant. HT: Vales.

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The second one is John Butler playing Ocean. I am floored. HT: Sayash

[Edit, 5/October/2012] By the way, what you see John Butler doing with his left foot is use the wah wah pedal, first used to perfection by Jimi Hendrix (I think). Usually, the wah wah pedal is connected to the pick-up in an electric guitar, and is used to change the sensitivity of the pick-up at different frequencies. The guitar Butler is using is not electric. Prevailing opinion is that the microphone is plugged into the wah wah pedal is plugged into the amplifier. Do you know better?

Linux NooB to World: Can you help me out?

I use Ubuntu. I’m running 12.04 Precise. My laptop has a 64-bit i5 processor with an AMD Radeon 6550 graphics card. Trying to troubleshoot a failed installation of the proprietary driver for the graphics card is another name for the fifth circle of hell. I am not kidding.

[Edit: a correction, courtesy Sayash: X is the drawing system. It uses display drivers to interact with the graphics devices. The standard display driver is called “radeon” or “ati”. I wasn’t joking about being a Linux newbie.]

So as I understand it, the X system is the simplest video driver for Linux. It uses system memory (RAM). Then there are the fglrx drivers, an open-source set of display drivers that run the graphics card. There are also proprietary drivers for the graphics card written for Linux supplied by AMD. This driver–or set of drivers–is called Catalyst.

For a long time, I had just the fglrx drivers installed. I didn’t face much trouble, but then I don’t do much with the laptop that uses the graphics card strenuously–g++ runs just fine on standard memory. I installed the proprietary driver, with some trial and error and lots of help from people, after somebody told me about them. The proprietary driver is better-performing than fglrx. Transitions became smoother, for example.

However, the proprietary driver has a habit of conking out; it has done this twice before. Ubuntu would go back to the X system, I guess. Both times, all I had to do was to reinstall–I say “reinstall”; I mean type ./installer from a shell and press enter–the driver and all would be well again.

This time, though, I was locked out of the GUI entirely. And no amount of fiddling, wheedling, or ubuntuforums drudgery brought back the GUI. I tried installing fglrx instead of the proprietary driver. I still get only a shell when I first switch the computer on. I have to log in and say startx, which brings me to the Desktop without the Dock or the system tray. I then have to start or restart lightdm — the desktop manager to get to the Ubuntu login screen, after which everything proceeds as usual.

Unless the shell loses its connection with the X server, which happened twice… afterI had installed fglrx.

Needless to say, I am bugged. Has anybody seen this sort of thing before? Do you know what the problem is and how to fix it? Please please help.

Books to read in 2012-13

This is for future reference, posted here mostly because I’ve just realised that Facebook‘s timeline is useless at being an archive. These are all books by good writers, and I recommend them to anybody reading this and willing to listen. I will buy them the first chance I get–which, with my access to free money, means whenever the paperback editions come out. And the paperback editions will come out. They will, they will, they will.

[Edit (3/10/12): If you have suggestions, would you leave them in Comments? I have already had somebody tell me about Philip Ball’s The Music Instinct. {Edit: Go here for a less charitable review.}]

1. Ben Goldacre’s Bad Pharma: How drug companies mislead doctors and harm patients

I read this excerpt from the book in The Guardian. There’s also this TED talk. The book is about the serious malpractice committed in the pharmaceutical industry. Medical researchers are shills in the game. Anything for profit.

In any sensible world, when researchers are conducting trials on a new tablet for a drug company, for example, we’d expect universal contracts, making it clear that all researchers are obliged to publish their results, and that industry sponsors – which have a huge interest in positive results – must have no control over the data. But, despite everything we know about industry-funded research being systematically biased, this does not happen. In fact, the opposite is true: it is entirely normal for researchers and academics conducting industry-funded trials to sign contracts subjecting them to gagging clauses that forbid them to publish, discuss or analyse data from their trials without the permission of the funder./snip/

Missing data poisons the well for everybody. If proper trials are never done, if trials with negative results are withheld, then we simply cannot know the true effects of the treatments we use. Evidence in medicine is not an abstract academic preoccupation. When we are fed bad data, we make the wrong decisions, inflicting unnecessary pain and suffering, and death, on people just like us.

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2. David Quammen’s Spillover

Here’s an excerpt also from The Guardian. David Quammen gave a talk at NCBS recently, and was interviewed for Tehelka by a classmate from the Science-Writing workshop. If you have seen the movie Contagion, this subject is already familiar to you. I haven’t seen the movie.

It’s a mildly technical term, zoonosis, unfamiliar to most people, but it helps clarify the biological complexities behind the ominous headlines about swine flu, bird flu, Sars, emerging diseases in general, and the threat of a global pandemic. It’s a word of the future, destined for heavy use in the 21st century.We’re unique in the history of mammals. No other primate has ever weighed upon the planet to anything like the degree we do. In ecological terms, we are almost paradoxical: large-bodied and long-lived but grotesquely abundant. We are an outbreak.

/snip/

And here’s the thing about outbreaks: they end. In some cases they end after many years, in others they end rather soon. In some cases they end gradually, in others they end with a crash. In certain cases, they end and recur and end again.

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3. David Byrne’s How Music Works

Is music universal? Is creativity? Or genius? David Byrne offers an answer that shouldn’t be as surprising as it nevertheless is. The excerpt from he book is at Salon.

I had an extremely slow-dawning insight about creation. That insight is that context largely determines what is written, painted, sculpted, sung, or performed. That doesn’t sound like much of an insight, but it’s actually the opposite of conventional wisdom, which maintains that creation emerges out of some interior emotion, from an upwelling of passion or feeling, and that the creative urge will brook no accommodation, that it simply must find an outlet to be heard, read, or seen.

/snip/

Presuming that there is such a thing as “progress” when it comes to music, and that music is “better” now than it used to be, is typical of the high self-regard of those who live in the present. It is a myth. Creativity doesn’t “improve.”

/snip/

It seems that creativity, whether bird song, painting, or songwriting, is as adaptive as anything else. Genius — the emergence of a truly remarkable and memorable work — seems to appear when a thing is perfectly suited to its context. When something works, it strikes us as not just being a clever adaptation, but as emotionally resonant as well. When the right thing is in the right place, we are moved.