There are truly many ways to increase the loudness of your iOS devices.
You can always connect your device to a good stereo speaker system for a better sound output. You may also use audio accessories to amplify the audio. If you have a jailbroken device, use Cydia apps like Volume Booster to get the maximum out of your iOS device.
Is there any other way to boost the music volume blaring out of the iTunes music player? Yes, there is, and the solution may raise quite a few eyebrows for it is downright silly.
Crank up Your iOS Devices Volume:
This unique solution, a never-seen-before idea comes from Reddit.
Check the basics: More often than not, a lot of iPhone users have volume limit on their device. You may want to navigate to Settings > Music > Volume Limit and make sure the Volume Limit is turned off.
Solution: Hit the play button and then put your iOS device — iPhone, iPad or iPod Touch — in an empty glass vase or a jug.
That’s silly, I know. But hey, it works!
You can also cup your hands around the speaker to get a louder sound effect.