Many synthesizers that are marketed as "four voice" instruments visibly feature four similar, independent sets of controls, giving impression that each voice could be tuned separately. However this means that the note sounds differently depending on which channel plays it! Is this problem somehow addressed?
For instance, if I press C and E on MIDI keyboard connected to the synthesizer like this, the synthesizer will pick a couple of its four channels to play these two sounds. What happens if I press E and G then? Will E be played by a different channel now?
The problem looks even more obvious for monophonic synthesizers that can be "cascaded" like Moog Minimoog Voyager: "connect up to 16 of them to achieve some serious polyphony." But each device obviously has its independent set of controls! Should the performer then care to tune all 16 boxes identically or I am just missing some piece of knowledge?