There are two designs of base for this model. The base you choose depends on the type of phone you use. If your phone has a loudspeaker along its bottom edge use the iPhone base. If the loudspeaker is anywhere on the back of the phone use the Galaxy base.
Print out the parts of the base that you are using onto thin coloured card. Any coloured photocopier card should be ideal. Choose two complementary colours of card.
This project is the Mk II new and improved version of the Phono-Horn project also available on Instructables here.
It was originally published on www.robives.com
Step 1: Making the Horn
Fold over the end tabs to make a triangular section tube on each of the eight horn pieces. This gives strength and rigidity to the open end of the horn.
Step 8: Galaxy Base
Glue together the two sides as shown.
Fold the two end sections in and glue them down being sure to keep everything lined up and not twisted.
The base is designed to be usable with a wide range of phones. If your phone has a speaker towards the bottom edge of the phone back like the Galaxy S2 and S4 then cut out the hole in the top centre of the horizontal square tube. Line up the long horn tube with that hole and glue it down (Left picture). You can then cut a hole in the horizontal tube which matches the position of the speaker phone.
If your phone has a speaker anywhere else on the phone back then there is no need to cut into the horizontal tube at all.
Position the long horn tube side to side on the stand so that it crosses the position of the phone's loudspeaker and glue it into position (right-hand picture.) Cut a hole in the long horn tube so that is lines up with the phone's speaker.
Step 15: Making the Base for IPhone
Fold up and glue the long horn tube as shown.
Fold the two end sections into place and glue them down.
Glue the tab of the long horn tube to the cross piece...
...then fold it over and glue it down as shown.
Assemble the two triangular section cross pieces.
Glue the cross pieces to the grey areas on the back of the side pieces.
Position your phone on the stand and mark where the speaker meets the stand. Carefully cut out a hole in the triangular stand piece with a sharp knife.