wideye is correct - the Vocalist VR is in essence the same unit as the Access. It is basically a harmonizer with a built in reverb. It is designed to provide "vocal harmonies". It can provide up to 5 part harmony (high, higher, low, lower and double)
It is designed to be a MIDI controlled effect unit. Send a MIDI signal to the unit which controls the harmony. When you plug a mic into it (or a line signal) and send an analog signal into the unit, the unit provides harmony (based on the MIDI notes it receives). There are various ways to control the harmonies - useing chord patterns, useing scales or creating specific harmony notes (via a MIDI keyboard).
I use mine in the following way. I use one "track" of my sequencer (Cakewalk) to play either chords or specific notes - this performance data is then sent to the Access. I can then either plug a mic into the access (or take a line out from my mixer - which has a pre recorded "lead vocal" track). When the Access receives the "lead vocal" part, it provides whatever harmonies I've requested. The unit has a stereo out to allow panning the hamonies left and right.
There has been much debate about the "mechanical nature" of machine produced vocal hamonies. I find it best to supplement the Access harmonies with one or two real harmonies. In fact, I will often use the Access harmonies as guide vocal parts (to help stay in tune) and record real vocals "doubling" the access.
It will never replace good human voices it can be a useful studio tool. It can certainly reduce some tracking time (if you don't have to pay vocalists to multi track harmonies).
