IsoPac F is a medium vocal booth that is also great for isolating and recording guitars, brass, woodwinds, and other acoustic instruments. If reflections off the front shields during recording are a problem, a few S2 SORBER baffles can be Velcroed to the offending shields. Attach them at the same height of the mic.
IsoPac F uses the STC4 and STS4 lid sections. These lid sections are 4' deep and work well on a booth of this size.
As with all of the IsoPacs, this one may be customized to fit your sp