We have to spend long hours underwater and needed both a comfortable immersion environment and an easy way to get in and out. The pictures might give you some ideas for constructing your own spaceship.
Acoustics: The booth is soundproofed with insulation and multiple layers of 5/8" sheetrock and soundboard - primarily so that we are not distracted by spurious sounds, but also so that we can play the audio loudly without bothering other developers. The sound system is a 5:1 with 8" speakers placed 12-18" from our ears . This achieves the high directionality associated with headphones while getting mid and low range frequency responses that are not possible with headphones. We also found headphones to be impractical - they added an annoying step each time we went in and out. The room is an irregular hexagonal shape to break up the standing waves. The front three walls are fairly hot (plywood directly under the cloth) while the back three walls are dead (fiberglass under the cloth). The amplifier controls are easily accessible while underwater.
Workspace: We needed to switch quickly from developer mode, with a normal desktop and nearby monitors, and performance mode, where we have full range of movement playing the instruments. The desk slides 18" and the monitors swivel out of the way, so that we have a full range or arm movements without bumping against anything. The seating is tilted back 150 to provide a more relaxed position when viewing compositions and we added a headrest.
Lighting: A lot of light leaks around the edges of the HMDs, so we need to have a completely dark room while working underwater. Easily accessed switches control both the room lights and the monitors. The overhead lights are LEDs because compact fluorescents interfered with the Hydra.
Ventilation:An acoustically isolated 5000cfm fan provides a fresh air supply within the booth.