Thanks abacus.
My use of MIDI is very basic and simple, and it works, but it never hurts to learn more. I have already had a look at the article about audio interfaces, so now I am trying to find a unit that suits my simple needs. MIDI in, line out to amps, and computer connection. To get one of good quality I will probably get a lot more than I need, but I am used to that. The only thing I need is the audio interface to get started with Pianoteq. But I have enough gear to keep me happy, so no need to hurry.
casaet