Having a tailpipe does make a different sound and quieter too. You might try cutting the tail pipe off right behind the muffler, just make sure you are not cutting an exhaust hanger out of the system and letting the muffler hang un-supported. If cuting the tailpipe off, you might consider buying or having an exhaust shop put a turn down on the pipe. It will be louder, resonate more and should make it deeper sounding.
I have a 40 on mine with a turn down. It has a nice, deep and typical flowmaster sound but I am getting a little tired of the noise and will probably get a tail pipe made for it. You might keep your old tailpipe handy in case you decide to put it back on.