Given that the other good advice has been disregarded, are you trying to buss your vocals through the DM4800? Then send that buss to an assignable output? If So Then:
Find which channels your vocals are on. Lets say they are on CH (modules) 1-4. Now find the large gray area full of buttons next to your fat channel. It is labeled "Output Assign".
Hit the SEL button on channel 1, and then hit the "1" button on the "output Assign" area. You have now assigned channel one to buss 1.
Now SEL CH 2, and hit the "1" button again. Now vocal 2 is also on buss 1. Do the same for CHs 3 and 4. Now Vocals 1-4 are on buss 1.
Now go to your routing screen (ALT/ROUTING/Output tab), and start from the right:
Use POD 4 (knob below screen on the right) and move the arrow down one click to "Buss/Direct", Now move POD 3 to move that arrow down to Assn Send.
Now go to the left again and use your arrow keys to move the selection down to highlight "1". Now use the jog wheel to change the entry to bring up "Buss1/DIR1"
It is flashing. Hit "enter" to make the selection permanent.
Now, make sure you go to your DM's buss layer and bring up the volume on Buss 1. Bring it up to 0db (Unity). Mix the vocalists inputs individually.
And finally, plug a TRS 1/4 inch cable into the Assn send jack and the other end to an available input in the Audio Box..
Another way would be to go into the presonus digitally. I.E., you could assign the Buss's output to the DM's S/PDif out, or even the ADAT out, but you will only be using 1 ADAT or 1 S/PDif channel.
Another common way to do this is to just buss your vocals to your normal STEREO buss, and assign THAT to any analog or digital output. The advantage here is that you can pan your 4 vocalists according to their position on the stage over a stereo image...something not available on the busses. If you have 2 channels available on your Audio box, simply assign the stereo bus out over 2 channels of ADAT or S/PDif and into the audiobox.
Many possibilities here...of course the FW card would be the real way to go here. you could send the audio box's outputs out over ADAT into the DM, and then send each channel into your DAW. (I am assuming it's Studio One, since it came with your Audio Box)
Good luck
