don't choose a great river as a main pre for rap vocals, the Pendulum or vipre either.. they're to colored.
you need a clean pre like dan said.. a avalon 737sp. its a unit used everyday in hiphop with a u87,414 etc..i got sick of this combo but the results speak for themselfs.
Check out
the Focusrite isa220. i have this pre along with the avalon. the avalon has a rounder sound imo, but some artist just don't sound right through it.
with the isa220 i haven't had an issue of an not sounding right through it.
my main vocal tracking mics are:
Neumann u87ai
Shure KSM44
Rode K2
Blue Kiwi
Monitors,
BM15a's are awesome. to hell with the mackies. not to many monitors besides adams and a few others are even coming close to dynaudio.
the bm6a's are rather rather accurate monitors and for $900 they can't be beat really in a small control room. they translate very well too.
as for the robbie. i heard one last week. i haven't had a chance to run a session with it.. but remember the robbie is just a pre where the focusrite and avalon are ch.strips. they offer great compression, eq, deessers.
now with $4000 just for pre/monitors...
PRE:Focusrite isa220 $1500 new
Monitors: Dynaudio BM6A $899 new
Leaves with cash for another mic or acoustic treatments.