[Falcon21]

Hi,
 
First, i'd like to mention that i am new to using amp for headphone.
 
I recently bought a Sennheiser HD449 for use with my PC/ipod.
My usage would include almost everything on pc, music, movies & games.
But it won't sound good at all with either(pc/ipod).
 
So, after a little research i ordered E6 from ebay.
 
Now, it made no difference in powering up my Hd449, it still sounds anemic.
 
Though, I tried my E6(16 ohms output) with my ipod paired with Sennheiser CX300(imp 16 ohms) and i must admit it sounds great!
Also, with PC when using my regular logitech gaming headphones(don't know the model), it sounds great!
 
I am guessing its because of the power(output 16ohms), is it?
 
Which Fiio amp should i go for my HD449s(imp 32 ohms)?
 
I did read about E10(32 ohms output), but its a DAC and don't have a line out like in my E6.
That being the case, how/where would the E10 take line in/source from?
 
Am i looking for a wrong product?
 
Should i go for E9(16 ohm output) instead? It has line in and out. And can be connected with PC headphone jack/ipod headphone jack.
 
My options: E9, E10 or E11.
 
My priority is not portability as E6 works fine for that purpose. I really want to drive my HD449s optimally.
But if E11 can make both, portable n desktop setup. I can also consider that.
 
Also, I am planning to buy Audio Technica ATH M50 next, so plz suggest an amp accordingly.
 
Does the amp output power 16 or 32 ohms makes a difference? What's the difference, or which is better?
What's the difference between 3.5 & 6.5 headphone jack adapter?
 
Sorry, it may seem confusing but i tried my best to explain. Consider me a novice.