19 May 2010

Manned spacecrafts

I found this nice little book from 1968 with the title "manned spacecrafts".

It's really interesting to read. First of all because it is about the rocket race between USA and Sovjet and the early years of the cold war and it's about H-bombs and spy reconnaissance planes and the first satellites.
Secondly because it gives a sense of the level of the technology at this time and how the voyages into space must have expanded every little boys fantasy with strange planets and advanced zivilizations.
Besides this it has fantastic graphics in it.

17 May 2010

Invention of the speaker

I just read this autobiography by Peter L. Jensen (1886), called "Jensen, højttalerens opfinder" (1948). The history about the invention of the speaker varies depending on the source The earliest small speakers used in telephones was invented in 1860-1880, but the use of speakers to amplify the voice so that a speech could be heard by thousands at the same time, seems to be realised by Jensen in 1915. The speaker was based on the moving coil principle, which was already known, so he didn't get a patent. Some guys from AT&T got it almost 10 years later due to some improvements and more specific descriptions.

The book describes Jensen's work with Valdemar Poulsen on the first radio transmissions and the race against the spark transmitter of Marconi. And how he moves to U.S.A. in 1909 and experiences really loud feedback for the first time when testing the loudspeaker prototype. There are also stories about the invention of the electrical turntable cartridge and the radio tube. So the book is both a 1st person story about the early days of electrified media and a really interesting adventure of the son of a fisherman who became an important inventor. I borrowed it from this guy who got it from his father.

10 May 2010

Wien Bridge Oscillator

This morning I just HAD to do a sine wave oscillator!

And so far it works... It is a Wein Bridge circuit. I don't know exactly what that means, but it is based on feedback in an op-amp, and and instead of a thermistor, a small lightbulb is used to stabilize the feedback. Charming solution, I think... I'm using one of the most crappy opamps, the LM741. It is old and noisy but even with this one the waveform seems quite OK.
And the spectrum analyzis confirms it. It's actually very pure!

... and clean up the breadboard... I always make a mess...

08 May 2010

Touch represented at Spor-festival 2010

BJNielsen, Mike Harding and Jana Winderen

The label "touch" was represented at spor-festival with a concert by Jakob Kirkegaard, BJ Nielsen and Jana Winderen and a seminar led by Mike Harding, director of the label.
At the seminar Mike talked about the history of the label, which was founded in 1982. He also talked about the physicality of the media on which the music is released. The importance of the paper for the digipack and the colours, fonts and size of the booklet and all that. This was very interesting. All these things that music consists of, that is not the actual music, he refered to as "the other" and said that you should never forget "the other". I agree.

Headphone festival

The Headphone festival was good!
There were live concerts by Simon Roy, vectral, Morten Riis, Jonas Olesen and me. Also compositions by other artists were presented, including Rune Søchting, André Falsig, Stormhat and Karsten Pflum.
Simon Roy



Relaxed audience

A guy who wasn't allowed to borrow headphones, but participated the best he could anyway.

A pair of really ok dudes

...and the one dude smiling on an orange-furniture-device... Who wouldn't:-)

The concert was held in the foyer at Musikhuset Aarhus. Not the most charming place in town but quite many people came by and listened. The good thing was that many of the guests were people not used to this kind of experimental, electronic music and it is allways interesting to witness the different reactions. This 10 weeks old guy responded with a smile...

07 May 2010

Headphone Concert preparation

Tomorrow I will be playing a concert at the Spor-Festival in Århus, Denmark. It will be a headphone concert afternoon and many artists have made works for the event and some will play live concerts, including me.
So, as usually, I'm interested in the transition between digital and acoustical representation of music; the convertion that gives the music physical, percievable attributes. I like to think of is as a birth.
For generating sound material to this 21 minute long head-phone-composition, I made this setup.

It's a metal plate (from a stove) hanging in a vertical position, with four speakers placed on it. The four speakers ar connected to an amplifier. From a very simple max patch I send sines or squarewaves at individual frequencies to the speakers. This way the speakers appears as vibrating, electromechanical objects, rather than as a media interface, which is the role that they normally have.

The metal plate resonates and the mix of speaker sound and resonating metal plate is recorded. It gives some really nice drones.

The mic is placed as close to the plate as possible to catch the small modulations emitted from the plate.

This is the proto type and me...

I will upload some sound from this soon.

The mail man just brought me this from China.

It's a backlit display for a Arduino project. But more about that later...