I am recording ambience and sound effects for a room and there is one open window in the room with traffic outside. I was wondering if that traffic sound coming through only the window would be stereo or mono?
I'd record it stereo and if you need mono to fit into the mix or scene better just use one channel. Depending on how large the apartment is supposed to be you could mix and match the channels used.
Are you recording ambiances and sound effects to be reproduced inside a room through speakers? Like a sound installation? Or are you recording the ambience of a room with an open window?
It's always better to record more and have the material to choose from later, so I suggest recording in stereo.
For indoor effect I suggest using mono (it is coming through one window) and stereo recording for outdoor effect.