This website shows you how you can connect two speakers together on a piece of wood. 

You can see my device in this photo:

The advantages of such procedure include:

- possible sound effects from:

         * speaker sound being blocked by a piece of wood,

         * penetrating sound wave mixing with two speakers attach face to face.

- protecting the speakers diaphragms (speaker cones) so that you can put them inside the cardboard or laptop bag.

There is a similar article that I published on Instructables website:

https://www.instructables.com/id/Double-Speakers-on-Wood/

You can see my encasement idea in this YouTube video:

Step 1: Make the Device

You can trying using electric or manual drill to wide the holes before you insert the screws. Using the drill will:

- reduce the chances of cracking the wood with big screws,

- make it easier for screws to penetrate inside the wooden block.

Step 2: Test the Device

You can see another video of my device connected to mobile phone:

Warning: Keep in mind that there is a danger of you burning the audio output because some audio outputs cannot handle low impedance loads (line out). Try Hi-Fi speaker outputs.