In the days of hardware based electronic crossovers, it was necessary to send your bi-amp signals to separate power amps and then connect to your speaker's high frequency and low frequency drivers with separate cables or a custom wired cable. This made for a larger truck pack having more cables per speaker and a greater number of connection points between the board, crossover, power amps and speakers.

Today's electronic crossovers, power amps and high current speaker cables have simplified bi-amp cabling significantly. In most cases, bi-amping is done with one cable per speaker since the power amp contains an internal electronic crossover and utilizes a 4-pin speaker cable such as Carvin Audio's PRO25TL. Carvin Audio's DCMLx power amps feature a software electronic crossover and TRx2000 series loudspeakers can be bi-amped using a single 4-pin cable. All that is required is the proper settings on both the amplifier and loudspeaker and bi-amping is as quick as connecting a cable.  

Using a power amp with processing, such as Carvin Audio's DCMLx series amps, allows the amps to be set-up for bi-amping with a laptop or via the front panel controls. Either way, the power amps can be configured before they are packed for the truck. This saves time when setting up the system at the venue.

Here is a video that describes the set-up of the DCMLx power amps in bi-amp mode and TRx2115 loudspeaker.