In some cases, to play the bass through PA amplification, it is plugged into a direct box or DI, which routes the signal to the bass amp while also sending the signal directly into a mixing console, and thence to the main and monitor speakers. When a recording of bass is being made, engineers may use a microphone set up in front of the amplifier's speaker cabinet for the amplified signal, a direct box signal that feeds the recording console, or a mix of both.
Since there are so many digital pianos worthy of your attention in this catalog, you may want to narrow down your choices using some of the search options on the sidebar. For example, if you select stage digital pianos under the category section, you'll be presented with all the digital pianos that were made for the stage. Once here you have the opportunity to drill down even further and can search by topics like number of keys, MIDI/USB Connections or by whether or not the digital piano has built-in speakers.