TLDR: I’ve got a fairly unique problem and I’m hoping you all can suggest some ideas - I’m installing a sound system in my camper van. It’s a big van, interior is 6 ft wide by 12 ft long, 6 ft high ceilings. Here’s a photo of the interior - think of it as basically a tiny studio apartment. My main issues are speaker positioning and room treatment in such a small/weird space. Any advice is very appreciated!

Speakers are the Infinity Reference 5030CX system (2x woofer, 2x tweeter, 2x crossover package) as the main/“front” speakers and a pair of Infinity Reference 5032CFX as secondary/“rear”. I have a few existing decent amps I’ll be testing out so that’s not an issue.

As for speaker positioning, the main place for listening is going to be the bench area in blue. Here’s a second photo showing what’s behind the bench - basically just the side slider door with some acoustic foam on it. As far as I can tell I more or less have two options for speaker positioning: 1) four corners approach, left in the rear and right in the front, all pointing towards the bench, or 2) “traditional” arrangement with speakers mounted on the kitchen wall facing the bench, plus the rear speakers somewhere on the bed walls/rear doors. I can’t decide between these two - the second has the benefit of soundstage if you’re sitting on the couch but then I would think that the “rear” speakers on the bed would interfere with the soundstage? Maybe set those to mono (?) The first approach/four corners style would probably require some sort of delay, plus mounting would be a royal pain in the ass, plus if you’re sitting on the bed you only get a left channel right in your face… tricky.

I’m a big believer in room treatment and I know it can absolutely make or break a setup. Unfortunately this is a very tricky one of course - obviously this is a terrible environment compared to a normal room. The van has solid hardwood floors, large 1" thick plywood walls for the bathroom, plastic wall sheeting and of course the walls are thin sheet metal. I imagine this setup is more or less what you all have nightmares about. My main ideas are to maximize absorption by throwing up a bunch of wall panels and coverings. I don’t have much space for a trap or diffuser - this is a small van, space is at an extreme premium and I don’t even have space for a coffee machine - but I’m willing to try to get creative if there should be a significant improvement. I could probably fit maybe two tri-traps in a corner or two. If there are any other materials or suggestions (coatings for the walls, adding weight to the plastic, etc) I am also open to changing any of that. I did already throw up some 1/2" thick PET felt hexagons on the slider door (the second photo I attached of the bench+slider, photo taken before I put up the hexagons) which will hopefully help but I heard that these aren’t very effective so maybe a 1" panel would be better?

So, if you made it through all that, main questions are 1) how do I position my speakers, four corners vs “traditional” vs something else? 2) how can I maximize absorption in the tricky space I’ve got? 3) any other ideas for making this setup sound good using what I’ve got?

I’ve been doing a bunch of research and experimenting but this seems to be a real tough one. Any advice at all is very appreciated!