I don't work with PSRs - I'm more into professional recording, but I'll try to answer your questions. I'm confused with
the term "live sounds". Are you refering to
DSP FX (Reverbs,Phazers,Delays and all that stuff) or Instruments (Guitars,bases,organs,pads,leads, etc)?
In either case the transfer of the sound (or program) from one instrument to another is only possible when their on board resorses and software (or SYSEX) are identical or similar (more of a conversion issue). To put it another way, You can only make one unit read the sounds of another if they are compatible.
I really don't think that the two different PSR keyboards have identical waveform data and FX. And I think that data transfer is more of a professional synth thing.
I haven't played with PSRs in over a dacade, but I'm sure they are a lot of fun!
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A gentleman is one who never hurts anyone's feelings unintentionally.
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