The Icon Horn Loudspeaker

Aim:

The aim of ‘The icon horn loudspeaker’ mechanical engineering project is to design an efficient horn shaped loudspeaker which works with Nokia Lumia Icon smartphone.

As you know there are lots of dock speakers in the market for smartphones. But most of these speakers use electricity for amplifying audio. What we are going to do here is to design a non energy using loudspeaker that can be used for smartphones.

As you know a conical loudspeaker need no electricity to amplify sound, the sound gets amplified due to its special shape. The same goes with a horn (I am talking about animal horn not automobile horn). In old war movies we see warriors using horns to make sounds signalling the start of a war or the arrival of a hero. We are adopting the design of this natural loudspeaker for our product.

Now, we are not Steve Jobs but mechanical engineers. There are products like this already in the market. So what is there for us to do? For us, as always, design matters. And to us design is about efficiency not looks. The horn shaped smartphone amplifiers out there in the market are not well designed  in terms acoustic mathematical theory that dictates the cross-sectional area of the horn contour, and hence are not optimized for sound. Our aim is to design a horn loudspeaker following mathematical theories.

Horn Theory:

How does a loud speaker make sound loud? As we know sound travels waves. In free space sound waves will move like a ripple in 360 degrees in a spherical manner. If we move that sound source and keep it on a flat floor the sound waves will get to move outward only through a semi-spherical area. But the sound waves that are hitting the floor will reflect and amplifies the sound by two. Now if we reduce the spherical area by 1/4, let’s say we place the source on the floor against a wall it increases the loudness by 4 times. In short we can amplify sound simply by directing it to the audience. This is what a horn do. It directs the sound waves to its audience by preventing them from scattering everywhere. A typical horn can increase the perceived loudness by more than 8 times.

Design Process:

To simplify the process we are not designing a product for all the smartphones, as they vary in sizes and locations of their speakers are different it is practically impossible to come with such a product. So we are making this suitable for only one phone ‘Nokia Lumia Icon’ smartphone. The design requirements listed are:

• The design should be done for Nokia Lumia Icon smartphone without compromising the position of its speaker, working of its volume buttons or the functioning of its touchscreen.
• The design should use Tractix horn contour for maximum loudness and musical performance.
• The design should be able to be manufactured via 3D printing
• The phone should be self-standing
• The loudspeaker should be easy to fit and remove.

Download full project report here - http://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?article=1253&context=mesp