I was right, just a 7th chord with an aug (sharped) 5th. It's a pretty cool chord, play a Bbmaj7 with a root on the 6th (6x776X) then go to a D7+5 root on the 5th (x5857x) then to an Ebmaj7 root on the 5th (x6878x). It sounds nice, nice voice leading and resolution (or whatever its called :-P)