Introduction: Interchangeable Horn Phone Speaker

What will the fashion conscious phone speaker be wearing this season?

Well, a fetching collection of stylish horns for every occasion, of course.

Lets then start with the fashion show without further ado!

Step 1: Night at the Museum

For those formal occasions, a stylish horn with smooth, classic lines, with a sober copper finish. A classy, understated number.

Step 2: Kids in America

This horn in bright, striking colours is perfect for those days when you just want to have fun, fun, fun.

For the young ones and everyone else young at heart.

Step 3: Singing the Blues

Your favourite phone speaker should be able to accompany you through those darker moods, and this horn in purplish hues fits that role perfectly. Pass the Prozac, please.

Step 4: Mighty Mouse

For those who don't have to prove anything, a small, colourful number which warns: don't mess with me. Dynamite comes in small packages.

Step 5: Full Disclosure

We all know about the poor rabbits that have to suffer in laboratories in order to test if beauty products are safe for us humans.

Unfortunately, fashion is a merciless master, and in our case, too, there have to be victims, some of them shown in the picture above. And sad to say, they have to pay the ultimate price: decapitation.

Step 6: Lets Get Serious

The idea behind this phone speaker is quite simple: The top parts of soda bottles are cut off, painted and then screwed into a socket in the body of the phone speaker, consisting of the (modified) cap of a soda bottle glued in place.

As there are quite a variety of soda bottles around, many horn designs are possible.

The body of the speaker is very basic, so it is actually a minimalist design.

The design allows for the use of horns of different shapes and colours, but of course also different sound characteristics.

This design is actually the third one I tried, because the sound quality of the first two prototypes was unsatisfactory. The problem turned out to be the size of the sound cavity in the speaker body: If it is too big, the sound gets very boxy.

Step 7: The Measurements

The picture shows the basic parts and the measurements of the speaker body. As only 6 mm hardboard/MDF is used, thicknesses are all 6 mm or multiples thereof.

The body of the speaker consists of 5 squares of hardboard glued together. The necessary openings have to be cut into each one beforehand.

This design is specifically for my Samsung Galaxy S2, which has its speaker low down on the back. Therefore I had to add an extra passage to allow the sound to travel from the phone's back to the throat of the horn, which meant an extra panel for the speaker body.

Phones with bottom mounted speakers, like the iPhone, only need a direct opening between the speaker and the horn cavity, which means only 4 body panels will be needed.

It should be very easy to adapt the design and measurements to any phone with its speaker at the bottom or low down on the back.

Step 8: Getting the Body Panels Ready

In the first picture you can see the five pieces of 6 mm hardboard ready to receive their respective openings before being glued together. Note that panel 2 and 3 are already glued together, as they will be cut in precisely the same way.

At this stage the panels are a bit oversized, as they will be cut to size (94 mm wide x 80 mm high) after begin glued together.

The panels will be cut in the following way:

1st panel: Just gets a 30 mm hole precisely in the middle, to accommodate the horn socket.

2nd, 3rd panels (already glued together): Gets the same 30 mm hole as 1st panel, plus opening for phone to fit in, plus passage between phone's speaker and 30 mm hole (for sound to travel through).

4th panel: Only for phones with speaker on the back: Allows sound to travel from phone's speaker to 30 mm hole.

5th panel: Just a solid panel forming the back of the speaker body.

The second photo shows the five panels after being cut and ready for glueing.

Step 9: Socket for the Horns

Before glueing the panels together, we must first fit the socket into which the different horns will be screwed.

The socket consists of an ordinary soda bottle top, grinded/sanded/cut down to a depth of 11 mm, as shown in the first picture.

The second picture shows the bottle cap glued into place with two part epoxy glue and waiting to dry. Hot glue or silicone should work just as well.

Step 10: Glueing the Body Panels Together

I've found it easier to glue multiple panels like this together in stages, as they tend to glide out of position if you try to glue them all at once and then clamp them together.

I started with the first, second and third panels (the latter two already glued together). After that I did the fourth and fifth panels. The first picture show the results.

The second picture shows another view of the first three panels, and the third photo shows how the phone fits into its cavity.

After that the two final parts can be glued together, and the sides cut to their final size, resulting in the almost finished speaker body in the last picture.

Step 11: Final Touches

Now we have to add a ring to the horn opening of the speaker body, otherwise the horn(s) won't sit neatly on the body. (A soda bottle's cap doesn't screw down all the way to the big ridge on the neck of the bottle, and neither will our socket if we don't use some kind of spacer.)

The ring I used I made out of 4 mm hardboard, using a 29 mm and 44 mm hole saw respectively (first photo). The second picture shows the ring in position, but upside down, ready to be glued in place.

Finally, to tilt the speaker body backwards, I cut a 22 degree angled wedge off of the bottom. Of course there are easier ways to tilt the body backwards if you don't have a suitable saw. The backwards tilt allows bigger sized horns to be used.

To soften the lines of the speaker body, I traced a gentle curve at the top of its front side (third picture), and removed the excess wood on a disc sander (fourth picture, and actually depicting one of my unsuccessful prototypes).

Lastly the speaker body needs a base, and I used a 130 mm round disc I had on hand, also made from 6 mm hardboard (picture second from last). I used two 16 mm wood screws to fix the speaker body to the base. The position is not critical, but I placed mine nearer to the front of the base as the weight of the speaker is centred towards the back, especially with the phone in place.

Of course the final colour is up to you. I chose Rust-Oleum's Apple Red for the body, because it contrasts nicely with a variety of colours for the horns, and Rust-Oleum's Hammered Black for the base (last picture).

Step 12: Let's Get Horny

Of course the whole point of our project thus far was to accommodate different horns.

Luckily a wide variety of soda bottles is available, most of which use exactly the same thread for their caps, and will thus fit on our phone speaker.

I've found that most bottles measure 15 mm from the top to the big ridge on the neck (bottle on the left in the first picture), and that is perfect for our purpose. However, some have a deeper top part (bottle on the right in the first picture), and will have to be sanded/cut to the correct depth (second picture).

The third picture shows an easy way to mark the cut line for the horn on a bottle with a permanent marker.

To neatly cut along the line with a pair of scissors, I've found that it is best to cut in a gentle spiral towards the cut line, which helps to get the correct angle (fourth picture).

Painting the horns is quite easy with aerosol paint. If you take care, it is also easy to paint the inside and outside different colours without having to use any masking tape.

The last picture shows the collection of horns I've made thus far.