[gilliesjake]

Hi everybody,
 
I have hopefully a very simple question. I have a Digi 002 Rack Converter, which has a headphone amplifier which has a load of 150Ohms.

I have been looking for a good pair of closed head phones (for recording and mixing music) and have settled on the DT 770's mainly out of budget. 

A) I'm not sure whether to go with the 80Ohm or 250Ohm 770's. How far off the output load does the headphone impedance have to be before it distorts or damping happens easily? Which one would be better for a load of 150Ohms?
 
B) As I am also a guitarist so the mid's are relatively important as well, and thus am considering the 880's. How big is the difference between the DT 880 250Ohm and the DT 770 250Ohm? Also, is the spill from the 'semi closed' 880's dramatically more than the 770's? 

I'm sorry if the answers to these questions have already been answered in this thread somewhere, I am new to quality headphones and to head-fi and havent had much luck in-regards to the Digi 002. Thought it might be easier getting a direct response! 

Cheers!

 

[mikeaj]

Device specs are here:
http://avid.force.com/pkb/articles/en_US/User_Guide/en365819
 
The higher the headphone impedance (generally), the lower the distortion you get from the amplifier.  However, distortion of the headphones themselves is usually much greater than that of an amplifier anyway.
 
It says that the headphone output max level is 15 dBu (which is 12.8 dBV, which is 4.4V rms) for headphones of 150 ohms.  For headphones with higher impedance, it could be slightly more.  For headphones with less impedance, it could be a little or a lot less.
 
Output impedance is specified as 50 ohms, but is that the line output or the headphone output?
 
 
Anyway, based on this information, the 250 ohms would make sense.  It has definitely more than enough power for those, and supposing the headphone output's output impedance is really 50 ohms, that could be more ideal anyway.  (Furthermore, some people say that the DT 770 250 ohms version has a more balanced sound than the 80 ohms.  I don't know if that's really true though, or maybe just the result of output impedance interactions with some devices.)  As for 770 vs. 880, the 880 is more even in the mids.  There is a lot written on the subject of 770 vs. 880 vs. 990 if you look around.

 

[gilliesjake]

Quote:

Device specs are here:
http://avid.force.com/pkb/articles/en_US/User_Guide/en365819
 
The higher the headphone impedance (generally), the lower the distortion you get from the amplifier.  However, distortion of the headphones themselves is usually much greater than that of an amplifier anyway.
 
It says that the headphone output max level is 15 dBu (which is 12.8 dBV, which is 4.4V rms) for headphones of 150 ohms.  For headphones with higher impedance, it could be slightly more.  For headphones with less impedance, it could be a little or a lot less.
 
Output impedance is specified as 50 ohms, but is that the line output or the headphone output?
 
 
Anyway, based on this information, the 250 ohms would make sense.  It has definitely more than enough power for those, and supposing the headphone output's output impedance is really 50 ohms, that could be more ideal anyway.  (Furthermore, some people say that the DT 770 250 ohms version has a more balanced sound than the 80 ohms.  I don't know if that's really true though, or maybe just the result of output impedance interactions with some devices.)  As for 770 vs. 880, the 880 is more even in the mids.  There is a lot written on the subject of 770 vs. 880 vs. 990 if you look around.

Thank you Mikeaj!

That is very helpful, it looks like I may go with the 250Ohms then. I guess that way I have the option of using an amp in the future as well.
 
Does any one know the dB difference in the sound emitted from the back of the 880 compared to the fully closed 770?
 
Cheers