does the situation ever arrise that one might want to have several different preamps into one set cabinet of choice? I’m assuming the answer is yes. But moreover, does the rack mounted preamps provide the opportunity to switch preamps via foot switch, or something? Obviously if one were to use any solid state (or even valve) rack amp, it wouldn’t matter particularily which one someone used, but if someone had multiple preamps, the sound could be altered based on settings/design/etc…

The reason this subject comes into play in my mind, is that I listen to many bands who do not use just a standard amp and cabinet for their set. For example, the guitar or bass sound for Nine Inch Nails is very different from song to song. On stage, they do not even have amplifiers, except for the guitarist, who uses a cabinet (no amp head tho) onstage for feedback effects. The rest is all processed through racks, and their stage monitors provide their foldback, rather than a giant marshall or ampeg stack situated behind them.

I guess the question I’m asking, after all that… is… does they use multiple preamps (some are midi, probably, and some solid state, some valve, etc…) to achieve different songs per song, and is there a way of changing the source live, via a stomp box, or somehting.
Say song 5 in the set requires a midi controlled preamp, which plays sounds created by some computer offstage (or something). Would the guitarist have control over this, or am I starting to get into big bucks and big time professionalism, with stage techs, etc…

Does a rack mount allow me the option of addition to new sounds/presets… or is the convenience merely in size and weight?