This Palmer PAN 08 19" DI/Line Isolation 4-Channel Active Box is a multifunctional device. Each of the four channels can be used independently as an active DI box, line isolation box, or booster. The combination socket input accepts both balanced and unbalanced signals. The output has dual transformer balanced XLR jacks (front and rear).The signal level can be attenuated by 20 dB for microphone inputs, but can also be boosted in three stages by up to 18 dB for LINE inputs if necessary. With an output level of +12 dBu on a load of 600Ω (with 0.05% THD @40 Hz and an output noise level of less than -110 dBu), the unit meets professional standards. Another feature is battery power; the supply voltage may range from 9 to 18 VDC, thus, the PAN08 can also be used without main power and outdoors.