Balanced refers to a different circuit design. Others will fill in the details on that. All pre-amps are NOT balanced. Balanced circuits require cables with XLR connectors. One known advantage is that balanced i/cs are less susceptible to noise on long runs. Some amps require and/or sound much better when run balanced. Some items wiht XLR inputs or outputs are not "Truly balanced" but actually function as a built-in adaptor. Stand alone adapters are available.
