As far as I recall - and not 100% confident I'm remembering correctly - I wasn't using headphones but the other three were. My preference is always not to if I can get away with it, and being partially screened off helps - I could still hear the others acoustically but was getting some of myself back off the partition. Early on in my gigging career I was pretty committed to playing acoustically as much as possible - I'm much less purist these days and almost always use an amp on gigs if there's a drummer, but I think that helped develop things which are useful in amp-less one room recording now...