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Signal build

Speaker From Scratch

Start with the video, then use the science notes and recommended parts below to follow the idea behind the build.

Radio & soundBuildAudio

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How it works

What this project is testing.

A speaker is basically a controlled air-pusher. A changing audio current flows through a coil, the coil sits in a magnetic field, and the force on the coil moves a cone back and forth.

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The build demonstrates how an electrical waveform becomes sound: fast voltage changes become fast cone motion, and cone motion becomes pressure waves your ears can detect.

F = B I L

A current-carrying wire in a magnetic field feels a force.

Recommended parts

Products used in this project.

Affiliate links may earn Keystone Science a commission. Match ratings, values, sizes, polarity, and safety requirements to your own build before buying.

CQRobot Speaker 3 Watt 8 Ohm Compatible with Arduino Motherboard, JST-PH2.0 Interface. It is Ideal for a Variety of Small Electronic Projects.

speakeraudio

CQRobot 3 Watt 8 Ohm Speaker for Arduino and Small Electronics Projects

$7.994.5(457)

Panasonic Portable AM/FM Radio, Battery Operated Analog Radio, AC Powered, Silver (RF-2400D)

AM/FM radio receiverradio

Panasonic RF-2400D Portable AM/FM Radio, Battery Operated or AC Powered

$29.994.5(33K)

BNTECHGO 30 AWG Magnet Wire - Enameled Copper Wire - Enameled Magnet Winding Wire - 4 oz - 0.0098" Diameter 1 Spool Coil Natu

magnet wirewiring

BNTECHGO 30 AWG Magnet Wire, Enameled Copper Winding Wire, 4 oz Spool

$12.984.6(387)

LOVIMAG Strong Neodymium Disc Magnets with Double-Sided Adhesive

magnetmagnetics

DIYMAG Strong Neodymium Disc Magnets with Double-Sided Adhesive, 1.26 inch x 1/8 inch, Pack of 12

$15.994.4(22K)

10 EcoSwift 12x12 Chipboard Cardboard Craft Scrapbook Material Scrapbooking Packaging Sheets Shipping Pads Inserts 12 inch x 12 inch Chip Board 12x12

paper/cardboardfabrication

EcoSwift 12x12 Chipboard Cardboard Craft Sheets, 10 Pack

$6.994.2(81)

Usable craft/fabrication material, but Amazon review evidence is thinner than the main bench-tool picks. Review requirements and safety guidance before buying.

Syncwire 3.5mm Nylon Braided Aux Cable (3.3ft/1m,Hi-Fi Sound), Audio Auxiliary Input Adapter Male to Male Cord for Headphones, Car, Home Stereos, Speaker, iPhone, iPad, iPod, Echo & More – Black

audio source / phoneaudio

3.5mm Nylon Braided Aux Cable, Male to Male, 3.3ft

$7.994.6(119K)

Use with an existing phone or audio player.

Project files

Prints, kits, and downloads.

Diagrams, printable files, kits, or companion downloads will appear here when they are ready to use.

Coming soon

Contact

Events, speaking, collaborations, and news.

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