A 50's batsman is big heavy and expensive - and underpowered by todays standards - so outwith a studio environment that's not the greatest idea...
Slightly simplified, a modern bass amp is a preamp feeding into a power amp - and a lot of the same class D modules are used in them.... if you get a separate preamp, in this case in a pedal, and stick it in the effects return you can use it instead of the inbuilt preamp... which can be quite fun if you want a different tone or sound for something...