Midifying An Analogue Organ What is the end result?

[mrdee 1]

I know it is perfectly possible to equip an old, analogue organ/keyboard, even piano with MIDI ports.I would only like to know what happens after this has been done: does the organ/keyboard stay as it is and can its internal sounds be transferred via MIDI, or, does it give a possibility to connect over MIDI, but only with the use of a sound module or other sound source, while its internal sounds are being used in the way the instrument was, ie. analogue, with no MIDI transmission, or, probably the worst case scenario, has the organ become a sort of "dumb keyboard" after the conversion, ie. all it can do is send and receive MIDI information, but all the built-in sounds have been disabled and all it can do is send/receive to and from a sound module/sequencer.Could someone enlighten me what happens to the original instrumen tafter conversion, as I have an analogue Yamaha organ, which I am considering converting (or rather, have converted) into a MIDI instrument, but my decision will depend on what happens to the instrument after conversion.Thank you in advance for any advice.