Deliverable #2: Design

Materials:

  • Strong Neodymium Magnet
  • 42 AWG Enameled Copper Wire
  • Solder
  • 12-16 Gauge Coated Wire
  • 1/4″ TRS Plug
  • Audio Interface
  • USB Cable
  • Laptop & DAW
  • Misc. electronic devices
    (other signals that our pick-up can detect)

Schematic:

See below, a schematic of our design.

Essentially, will place hold our pickup near or against a device whose signals we will be able to capture in audible form; these signals will then flow through a cable to the audio box so that the computer can receive the signals as audio that can be arranged and manipulated.

Below is another image, showing the alternating flux and eddy current in this system.

source: http://farhek.com/jd/t5186r12/hf-faq/121…

Equations and Measurement:

To consider ways to quantitatively measure the function of our pick-up and attributes of the signals it would receive, we have been looking at this website: https://www.electronics-tutorials.ws/inductor/inductance.html

We plan to use the below formulas to measure the inductance of our coil, using the formula below:

Where L (inductance) is in Henries, i (current) in amperes, and s in seconds. We perform the measurement by placing a source signal near the inductor pickup. The pickup, ideally, will record the disturbance in its electromagnetic field, transmit this through the cable and to the pickup, which is connected to a multimeter. This meter will allow us to record the changes in current and voltage, over a specified interval of time. This will give us the information that we need to solve for the inductance of our Inductor Pickup. We also may decide to use different sources or tools as well, to see whether or not our math is reliable.

Compositional Plan:

Given that it will take a great deal of experimentation to determine what kinds of sounds we can capture using our pick-up, it is impossible to describe our composition in detail at this point. However, we can describe its components conceptually, outlining the textures and effects we intend to create in production. Fundamentally, we expect to create an atonal cacophony of the “silent” sounds that surround us. The projected structure is as follows:

Part A: A plain, simple, pensive presentation of the samples we’ve collected – distinct and unaltered, like we are laying out our puzzle pieces.

Part B: The samples will again be presented, unaltered and distinct (not layered), but now in a rhythmically organized fashion; the logic grows.

Part C: The samples remain unaltered but now begin to overlap; rhythmically confusion grows

Part D: The samples change, becoming altered by various effects (pitch modulation, tremolo, vibrato, various filters)

Part E: The samples combine to reach a peak cacophony

Part F: An awakening- the texture undergoes a sudden reduction, returning to a simpler arrangement analogous to that of Part A

Deliverable #1: Introduction

Intro:

The purpose of this project is to explore transduction and composition/digital production using a homemade inductor coil pickup. This type of pickup is the kind used in electric guitars, but our intent is to use the pickup in unconventional ways to explore how interesting signals can be audibly represented. Once we have audio samples of these signals, we will use a DAW to produce a “symphony” of these sounds. The project can be divided into several stages: 1) Research, 2) Building, 3) Experimentation, 4) Analysis and Digital Manipulation.

Research:

In researching various types of pickups and how they are constructed, we found a simple yet effective design that operates using the same basic principles as a guitar’s pickup. The specific type of pickup that we chose to create is an Inductor Coil Pickup. The design of this pickup consists of a strong magnet which is wrapped tightly by a very thin, enamel coated wire. The purpose of the enamel covered wire is to transfer the current along the length of the coil, as opposed to passing the current sideways between the wires. We learned in class that the coils of a magnetic pickup are capable of detecting the disturbances in the electrical field as signal waves interact through the process of induction, and that by connecting the ends of a coil to an amplification system, we can hear these systems – or, should we connect the output cables of the coil system into an audio interface, we can record the signals.

During research, we found that these pickups are capable of detecting much more than just the vibrations of a string – they are capable of picking up the normally inaudible frequencies, such as those from the infrared spectrum, that are emitted from everyday electronics (phones, remotes, modems, etc.), effectively allowing us to record and make audible signals that are otherwise inaudible to the human ear.

Building:

To construct our pickup, we will use: 42 gauge AWG wire, a neodymium magnet, acrylic or some comparable non-ferrous material, and a quarter-inch TRS plug. The magnet will first be secured between two small plates of acrylic. Additionally, a hand-drill will be placed in a vice, and the acrylic and magnet unit will be place on the end of the drill. When the drill is turned on, the unit will spin. We will then the secure one end of the wire to a small hole in the acrylic, and begin wrapping the wire around the magnet with the help of the drill. Once we have achieved sufficient wrapping, the other end of the wire will be secured to the acrylic. Additional wire will be used to create a cable with the TRS plug on the end. Once these steps are complete, we should be ready to begin using the pickup in the experimentation phase. This is the tutorial on which we have based our building procedure: https://www.youtube.com/watch?v=u6f-H_-C-2Y

Experimentation:

This phase of the project will be highly subject to change as we learn which uses produce audio and which fall flat. However, at this point in time, we hope to use the pickup to listen to the internal activities of various electronics. This video demonstrates some of the sounds we’d like to explore ourselves: https://www.youtube.com/watch?v=iIQKhPpNPE0 (1:52). Additionally, we are considering putting the pickup inside of a ferrous object (like a tin can), and seeing how being in such a space might alter the signal prior to it being received by the pickup.

Analysis and Digital Manipulation:

We will use various DAWs to analyze the signals recorded through the coil, such as Audacity (to perform spectral, frequency and other analyses) and Ableton or ProTools (to create the piece using these new samples).