Trying to get into Headphone Amps

[subzero]

Greetings!

 

I own a nice pair of Sennheiser's, and I've started to get interested in headphone amps. For reference, I use a laptop with a tinny soundcard. I've been looking at the:

 

FiiO E7 USB DAC and Portable Headphone Amplifier

 

and the

 

FiiO E9 Desktop Headphone Amplifier and Dock

 

This is going to be a really stupid question, but I don't understand the E7 and E9 relationship. What is the point of mounting the E7 on the E9? It seems like the E7 is pretty great by itself, no? What is the benefit of having both of them?

 

I'm sorry if I'm yet another amateur that has come along and is ruining the forum. Thanks in advance!

 

[wrcwill]

The E7 is a DAC/Amp, the E9 is just an amp (a more powerful one). So when docking the e7 on the e9 you get the DAC from the e7, and the amp from the e9.