E11 sufficient enough to power DT 990 Pro 250ohm headphones?

[alterndog]

I'm looking at possibly getting the DT 990 Pro 250, but only have a Fiio E11 headphone amp to power it. I know the 250ohm is pretty high and was wondering if the E11 would be efficient enough to power the HPs. I had done some searching and never found a definitive answer on this question. I don't have any extra money to upgrade my amp, so I'm stuck with the E11 (which I actually like fine). Thanks in advance for the responses. 

 

[NA Blur]

The E11 will do fine.  It is often more about the sensitivity of the headphone than the impedance.  The DT990 has a 96dB sensitivity making it not ideal for portable devices, but with the E11 amp there should be no issues with getting them loud enough.
 
You can learn more here:
 
http://www.apexhifi.com/specs.html
 
Here are the worst case numbers for the 250 Ohm DT990
 

Headphone sensitivity (dBSPL @ 1 volt RMS) 96 Headphone impedance (ohms) 250     Desired loudness (dBSPL) 110     Required power (milliwatts) 100 Required voltage (volts RMS) 5.01 Required current (millamps RMS) 20.0
The FiiO Specs can be found here:   http://fiio.com.cn/products/index.aspx?ID=100000038781911
The E11 is not the ideal amp for the 250 Ohm DT990, but it should work.  I would recommend something with a little more power for best performance.   Be sure to check out the $200 and under amp shootout here: http://www.head-fi.org/t/620775/the-sub-200-portable-amps-shootout-13-11-amps-compared/15