iPod Touch 5 vs iPhone 5s sound output (Line Out) I bought an iPod Touch 5 two months back, I love the sound quality of the device. But after 1 month when my brother bought iPhone 5s, I checked the sound output of the device through the same earpods that came with my iPod. The difference in sound output was huge, I am not talking about the sound quality but the loudness.

I checked everywhere but there was no proper explanation why the difference in sound is so huge.

Is it because the two DACs r completely different or is it something to do with Output Source Impedance?
That is very weird; do you have a European version?  The output power on those is heavily limited. That is the only explanation. 

I have both the iPhone 5s and the iPod touch five and they have the exact same output voltages and voltage drop when headphones are connected. The output power is the same, I have heard from a few sources that the distortion levels on the 5s is better but they definitely have the same output level. Be sure to verify that the equalizer is disabled and sound check is off