streaming set-up

[diastudios]

what do i need to do to be able to stream perfectly or good
what i have
2 imac
1 macbook
1 laptop
1 sony dcr-hc40 with firewire
1 tascam mixer dp-20
1 super strong mic
i got the volume coming out and the stream perfect but issue am having is basically getting the sound to come out in the studio so that show hosts can actuqally monitor their voices
If I hook a speaker to my mixer,i am certain there willl be an echo cos i plan on using 1 mic that picks up everything or should i use more than 1 mic,my mic pics all sounds

[cseeman]

If you use headphones you can avoid echo.