16. Applications and implications
For this week's assignment, we have to detail everything required for the development and creation of our final project.
What will it do?
The spinning speaker will be designed to create unique sound effects through mechanical means. It will achieve
its distinctive sound by using a rotating horn, which create a Doppler effect as they spin. This effect
modulates the sound waves, resulting in rich, swirling tones that add depth and dimension to the audio output.
Who has done what beforehand?
This project is based on the Leslie speakers, which were invented by Donald Leslie in the 1940s. They were originally designed
to enhance the sound of the Hammond organ, but they are now used with various musical instruments to create distinctive sound effects.
Usually, they have two speeds: fast (called "tremolo") and slow (called "chorale"). Older models might use tube amplifiers, while newer
models might use solid-state amplifiers.
What will you design?
Leslie speakers are usually quite large. One of the smaller models is the Leslie 145 with:
Height: 33 inches (84 cm)
Width: 29 inches (74 cm)
Depth: 20.5 inches (52 cm)
Weight: Approximately 122 pounds (55 kg):
I will make a more compact design, approximately:
Height: 7 inches (18 cm)
Width: 5 inches (14 cm)
Depth: 5 inches (14 cm)
Weight: Approximately 1.76 pounds (800 grams)
I will design the horn in 3D for later printing. The enclosure will be designed in SolidWorks and cut from MDF.
I will also design the rotation system and the board for the LM386 amplifier
What materials and components will be used?
| Component |
Number of components |
| LM386 audio amplifier |
1 |
| 10Ω resistor |
1 |
| 0.1μF capacitors |
2 |
| 220μF capacitor |
1 |
| 2.2kΩ resistor |
1 |
| 10μF capacitors |
2 |
| 470μF capacitor |
1 |
| 10kΩ potentiometer |
2 |
| 10w 80hm speaker |
1 |
| dc motor |
1 |
| 6V power supply |
1 |
| Aux. cable |
1 |
| MDF casing |
The necessary pieces |
| 3D-printed horn |
1 |
Where will they come from?
The components can be purchased from local electronics stores. For the 3D parts, they will be designed and printed at the university.
The MDF pieces will be designed and cut at the university.
How much will they cost?
Electronic components: $35.243
MDF: $6.84
3D prints: $0
Total: $42.083 dollars
What parts and systems will be made?
I am going to design and cut the speaker casing out of MDF wood. I will design and 3D print the horn,
as well as the speaker mount and additional support structures. I will design the electronic board in KiCad
and etch it on a copper board using a cnc.
What processes will be used?
- Test the circuit on a breadboard to check the sound quality.
- Design and cut the audio amplifier board.
- Test the circuit to operate the DC motor.
- Design and 3D print the necessary parts.
- Take measurements of everything and make a sketch of the casing on paper.
- Draw the parts in SolidWorks to cut them out of MDF.
- Assemble everything in the casing.
What questions need to be answered?
- Does the LM386 amplifier provide the desired sound quality and volume?
- Does the DC motor provide the necessary force to rotate the horn?
- What voltage is needed to operate the speaker and the motor?
- Does the audio output from the horn change the sound quality?
- At what speed does the horn need to rotate to achieve the desired effect?
How will it be evaluated?
- Sound quality
- Effectiveness of the effect
- Volume
