Legato and Retrig
Legato

Legato works best with monophonic sounds. Set Key Poly to 1 and try the following:

Hold down a key and then press another key without releasing the previous.

Notice that the pitch changes, but the envelopes do not start over. That is, there will be no new "attack".

If Key Poly is set to more voices than 1, Legato will only be applied when all the assigned keys are "used up".

For example, if you had a polyphony setting of "4" and you held down a 4 note chord, the next note you played would be Legato. Note, however, that this Legato key will "steal" one of the keys in the 4 note chord, as all the assigned keys were already used up!

Retrig

Retrig is the "normal" setting for playing polyphonic patches. That is, when you press a key without releasing the previous, the envelopes are triggered, like when you release all keys and then press a new one. In monophonic mode, Retrig has an additional function; if you press a key, hold it, press a new key and then release that, the first note is also retriggered.