Shure SCM268 - Analog mixer - 4-channel

Key Features and Benefits:

• Great value
  The SCM268 microphone mixer features six transformers inside: four transformer balanced XLR microphone-level inputs, one transformer balanced XLR mic/line output, and one internal low stray field, toroidal power transformer.
• Many benefits, little space
  All those audio transformers provide protection from RF interference, prevent ground loops, and make the SCM268 exceptionally quiet. The internal toroidal power transformer means you no longer have to deal with that annoying "wall wart".