An amp as it is, is too amplify a signal, period. And yes, an amp purpose is able to push out in terms of
watts, some amp are capable to push out more voltage into higher impedances while some don't. It all depends on how the manufacturer designs it. This is back to basic physics where
W = A * V
where W = watt, A = ampere and V = voltage
Not all products need an amp to shine as some are tuned and design to specifically work with internal amps from your portable devices like your iPad, iPhone, smartphones,tablets, PC's, etc
Often people misread thinking that low impedance don't need an amp where they should also look at the manufacturer's specification of sensitivity as it shows an indication of how much decibel of sound it can produce at 1mW of power
Take a look at the following examples:
CODE
Beyedynamic T1
Transducer type . . . . . . . . . . . . . . . . Dynamic
Operating principle. . . . . . . . . . . . . . Semi-open
Frequency response . . . . . . . . . . . . . 5 - 50,000 Hz
Impedance . . . . . . . . . . . . . . . . . . . . 600 Ω
Nominal SPL . . . . . . . . . . . . . . . . . . 102 dB (1 mW / 500 Hz)
CODE
Hifiman HE-6
Frequency Response: 8 to 65 KHz
Impedance: 50 Ohm
Efficiency: 83.5 DB
Weight: 502 g
To the uninformed, most would think that the T1 would need an amp to drive it optimally due to its 600 ohm nominal impedance while the HE-6 with its 50 ohm do not need one.
This is where they are wrong as the efficiency of 83.5 is much lower than the T1's sensitivity of 102 db. The Hifiman HE-6 is the one that requires
even more power in terms of power compared to the T1
How do u get the watt? I mean voltage is the impedance or ampere? Coz from what i know is that ohm thingy is like internal electrical resistant. But most manufacturer doest come out the watt and ampere needed to powered their product.
i know its stupid to compare an on ear headphone to an IEM,as that is wat i own..