Bose 901 VI flat?

I purchased a pair of Bose 901 VI speakers recently and a new Sony STRDH190 receiver.  I have wanted these speakers for years and finally got them.  Problem is, they sound flat and weaker than expected.  I adjusted the bass and treble to my liking but that only helped a little.  I have the Bose EQ that came with the speakers but i'm not using it due to new receiver technology.  Am i doing something wrong? I know these are great speakers with a great history.