To pump up the volume of your iPhone speakers, maximize the levels in the Sounds settings for the iPhone and in the apps you use, and acoustically couple the speakers to something that concentrates and directs the output of your speakers.
We can suggest you software based solution for this problem.
Use your volume button
Use the + button on the side of your iPhone to maximize loudness to the limits allowed by phone and app settings.
Open the “Settings” and select “Sounds” to maximize ringers and alerts. Set the volume slider fully to the right
Return to the home screen for the “Settings” and tap “Music”.
“Sound Check” adjusts individual song files for loudness, raising the volume of some of them, while reducing the volume of others.
“Volume Limit” is a handy feature to avoid blasting your ears when using headphones, but switch this off to get maximum loudness from internal speakers.
Tap “EQ”, which is an option in the “Music” settings. Tap “Loudness” in the “EQ” presets.
If ears are more sensitive, try others until you settle on your favorite.
There are also mechanical solutions
Sound radiates from an iPhone speaker in pretty much all directions, unless there is something to reflect it. When reflection occurs, the direction of sound waves change, so essentially is pushed in the direction of reflection.
You can use a combination of these effects to amplify your iPhone. Start some music on your phone and try some of these ideas:
- Place the speaker end of your phone toward a wall to reflect sound. Move closer and further to find the best result.
- With the speakers facing down, put your iPhone into an empty cup, bowl or vase. Sound reflects upward and — depending on the shape of the vessel — is amplified. The ideal bowl has a base about the size of your iPhone and flared sides.
- Try different materials — glass, plastic, metal, ceramic — to experiment with their different effects on volume and sound quality.