I have a CD-only system with 4 electronic components in a backless cabinet that is only 2 feet high and the speakers are pulled out at least 4 feet and this has worked very well, so I, too, second what Grannyring is saying.
But, if you can't get a TT into another room, you may want to approach it like a sub crawl, only in reverse in that, while playing something bass-heavy, you are listening for a room null along a given wall...avoiding a location plagued by standing waves.