I think all you guys are wrong. You should actually download the manuals of these things before responding. The Tascam interface he mentions actually has 4 outs so in fact two stereo mixes can be sent from the Tascam. Also the Behringer headphone amp allows more than one mix to be sent to the outputs. Each headphone amp I think can have a separate mix to be fed in individually and over ride the main mix feeding the headphone amps etc...

Jeff Evans
I think all you guys are wrong. You should actually download the manuals of these things before responding. The Tascam interface he mentions actually has 4 outs so in fact two stereo mixes can be sent from the Tascam. Also the Behringer headphone amp allows more than one mix to be sent to the outputs. Each headphone amp I think can have a separate mix to be fed in individually and over ride the main mix feeding the headphone amps etc...

ALL us guys are wrong and we haven't downloaded the manuals before responding?  did you READ the entire thread before making accusations?
 
my post NUMBER 2 (FROM November of 2012) above includes this:

yes, as long as your soundcard is capable of multiple outputs.  your signature says you have a toneport UX-1, I doubt you have more than 2 outputs on that, but the tascam 1800 does, albeit not many.  it has 4 outputs available.  you can set up a bus for each of the 4 outputs (assuming the tascam drivers allow for mono output, if the tascam drivers only allow for 2 stereo outputs, then you can only set this up for 2 people).

No one has done the homework on the Behringer Headphone amp though. You are all assuming only one mix can be sent to all outputs which is also incorrect.  I have used these headphone amps on a few occasions now and they are quite versatile in terms of what they can do.
 
Each headphone amp has an AUX IN on the front and not only that but a balance control between that and the main mix. So you could feed a main mix minus vocals etc to the amps as per usual and just send vocals to the aux input on an individual amp and then add the vocals in to taste along with music etc.  Rather cool. In fact you can feed 5 different stereo mixes into this headphone amp. As long as you have the outputs available from your interface. 
 
The Behringer does have XLR inputs for the main mix.
 
Not sure about the Tascam but the headphone out might even be able to supply a different mix as well but I think that might only be on the later models with that rather extensive software that comes with those models.
 
A good rule of thumb is if someone asks a question, download the manual and look at the block diagram first. It is generally a good idea.

Myself I'm to busy reading my own owners manuals :) 
I'm sitting here with my GR 50 manual as we speak. My son is lending me his Godin with the guitar synth output so now I have to remember how to set up a patch chain.. 
 
The Behringer sounds like it will do what 4 of the Rolls PM 50's will do but does not have XLR connections, They sell for $60 each. Best thing is you can mount it right on your mike stand. I run the board mix into the monitor in ( it's TRS stereo) and then my vocal mike has it's own level. 

Ok, I stand corrected, from 3 years ago, which I doubt the OP will ever see.

Kennybern asked about connecting his outputs to the headphone amp and that's what brought this 3year old thread to the top again.