my love grows thin
somewhere in the mist of another morning
I reach out
only twisted metaphors
where is the thick warmth of a body?
layers of tendons and blood vessels
I am the moon
against a backdrop of creased bedsheets
vainly pulling towards me
a red sea
a good starting point – stethoscope mic made from a contact mic and preamp
power supply for a condenser mic
Electret Microphone and Pre amp:
“Description: This small breakout board couples an Electret microphone (100Hz–10kHz) with a 60x mic preamplifier to amplify the sounds of voice, claps, door knocks or any sounds loud enough to be picked up by a microcontroller’s analog-to-digital converter. Each breakout comes fully assembled and works from 2.7V up to 5.5V.
The Electret Mic Breakout translates amplitude (not volume) by capturing sound waves between two conducting plates (one a vibrating diaphragm and the other fixed) in the microphone and converting them into electrical waves. These electrical signals are then amplified and picked up by your microcontroller’s ADC.”
This TI Precision design details the design process for a preamplifier to be used with electret microphone capsules. It explains the basic construction and operation of an electret microphone and uses an OPA172 to amplify the output of the microphone to common analog line level voltages.
Circuit Board Resources :
Handmade Electronic Music the art of hardware hacking by Nicolas Collins looks like a great resource. When I get back to London I want to modify the contact mics so that they can be placed on the body without the getting a humming sound this means i may need different wire or simply to use Plasti-Dip as described bellow:
Rule #11: Don’t drink and solder.
- When you are sure you have an electrically functional contact mike, cover the ceramic side with a piece of electrical tape—you can trim it around the circumference with scissors or a knife, or you can wrap the edges over to the other side of the disk.
- Find a well-ventilated space. Open up and stir your can of Plasti-Dip. As per the instructions on the label, slowly dip the contact mike end of your cable into the goop until you have covered the wire past the electrical tape (see figure 7.5). Slowly with- draw it and hang it up (preferably outside) to dry. Go away and take a break—this stuff is stinky. You can dip a second layer after the first one dries thoroughly, which can take a few hours. More than three layers tend to muffle the sound, so don’t overdo it without listening carefully after each new layer.
The tape and Plasti-Dip treatment serves several functions:
- It strengthens the connections between the wires and the piezo disk.
- It insulates the disk from electrical shorts, and prevents hum when you touch it.
- It waterproofs the contact mike, so you can use it to record underwater sounds, freeze it in ice-cubes, dangle it in a drink, etc.
- It deadens slightly the pronounced high-frequency resonance of the disk similar to the effect of gaffing tape on the head of an unruly snare drum.)
How can chelsea balance it’s self-taught ethos with class based teaching and a greater interdisciplinary bleed between the “fine arts” and other forms of creative practice
“You have to ask yourself what IS “the sound of a heartbeat” – To a layman its the bass “lub-dup” you can hear when you put an ear to someone’s chest, whereas a cardiologist is listening to the opening and closing noises of your mitral and aortic valves etc etc.
A: I actually tried this last night. When I pressed the piezo against my skin, it just made a loud buzzing sound no matter where I put it on my skin.
B: From my experiences with piezos this means it’s shorting or you are pressing to hard. Make sure the connections are sound, especially on any audio wires you’ve spliced in, and put something between your hand and the buzzer, maybe even a thin piece of cloth between your neck and the disk too.
I’ve used one up against my throat as a mic but it may not be sensitive enough to pick up a resting heart beat.
C: An electret microphone cartridge would be a good sound pickup. Some are pretty small. You might be able to find one small enough to stick in the end of the stethescope tube. Sparkfun makes one with an atached pre-amp: https://www.sparkfun.com/products/9964?
To power the speakers, we have a nice compact amplifier module: http://www.adafruit.com/products/987
A conventional microphone placed on, or a few inches above, a hard boundary surface will pick up the desired direct sound as well as delayed sound reflecting off the boundary surface. The direct and delayed reflected sounds will combine at the microphone to create comb filtering, with constructive and destructive interference causing peaks and valleys in the frequency response. The delay time of the reflection for most microphones would be in the range of 0.1 to 1 milliseconds, corresponding to cancellation frequencies of a few kilohertz and octave multiples. Since these frequencies are audible, the cancellation effects are also audible and are said to “color” the resulting audio signals.
By placing the diaphragm of the microphone capsule parallel to and facing the plate boundary provided by the microphone package, the reflected sound delay is reduced, and the resulting comb filter interference frequencies are high enough that they are outside the audible range.
The first is geophony – the non-biological sounds that occur, wind in the trees, water in the streams. These were the first sounds on Earth but there needed to be something to hear them. So that gives us the biological component; the biophony. And biophony is the collective sound that is made by all the species in a given habitat. And the third is anthrophony or human generated sound which I divided into two subsets, the first being controlled sound like music, language or theatre, and the second is incoherent or chaotic sound which we typically refer to as noise. One of my colleagues has termed that technophony. I encourage people to come up with their own terms for all this stuff.
One of the key points I’m trying to demonstrate with the exhibit is the concept of structured natural sound. The acoustic niche hypothesis posits that all of the biophonies in a healthy habitat have evolved in ways that the channels of bandwith of transmission and reception are reserved for and occupied by individual species.
To map the acoustics of ancient spaces, to understand how a church was designed to reverberate at certain frequencies
The event in question was Ephemera, a site-specific collaboration between the Canadian electronic musician Tim Hecker, German visual artist Marcel Weber, a.k.a. MFO, and Geza Schoen.
he decided that the solution “was not stacking things louder and heavier but working in a different way.” That meant working with voices, for one thing—a complicated-sounding process of using software to translate medieval choral music to digital synthesis and then, working with Icelandic composer Jóhann Jóhannsson, to write and record complementary new choral parts.
Love Streams tackles a lot of abstract concepts, like “live” sound, and synthetic sound, and rooms and space, and technology’s ability to complicate all those things. But it’s also about the ability to disappear into sound, to get lost in the contours of a slippery timbre, or to be made whole by a consonant harmony. At its close, those staccato vocal parts and that smoldering low end deliver a real emotional punch, the release to subtle tensions that have been building up throughout the course of the record’s hazy, unpredictable run. It’s a suggestion that, if you stumble around in the fog long enough, you might just find what you’re looking for.