Need help integrating my sub. Is an EQ the answer?

I have a "starter" system consisting of

Receiver: Marantz SR8500
Main: B&W 804S
Center: B&W HTM4S
Rear: B&W Signature 7NT (Inwalls)
Subwoofer: SVS PB12ISD

Once we finish remodeling the house I'll be moving my 804s downstairs into a two channel system and replacing them with 805S. In the meantime (and also planning for the future) I'd like to integrate my sub the best I can without spending gobs of money to do so. I have room placement issues and right now room treatments aren't an option (but might be in a future once my fiance get a finished downstairs living room). Whats the best way of getting rid of some dips and peaks in my bass response so that music and movies both sound their best. I'm more willing to compromise the sound of movies a little so that music can truly shine but almost feel that if music sounds great then movies will sound just as good.

I've read about the possibility of using an eq (parametric or other) to help flatten out the bass response. What would be a reasonably priced piece of equipment (under $500) that would help do this?

P.S. My SVS is connected to my reciver's sub out jack and its crossed over at 80hz.
You could try turning off the LFE channel and running the sub via the speaker level inputs in parallel with your main speakers. For a basic setting the crossover point of the sub s/b set to where your main speakers roll off; ie, if they are down 3db at 40hz set the crossover point for 40hz to start with.

Then, when the music is on turn the sub up until you can "hear" where it is placed. At this point start backing off on the sub volume until it is no longer localized; ie, you cannot locate it from its output.

If it is a downfiring sub I'd stick a nice thick piece of acrylic or granite/limtestone underneath it.

As for placement, if crossing it over at 60hz or less I'd stick it away from the main speakers. Don't put it in between them as the bass waves might interfere with the output from your mains and screw with your imaging/soundstage.

I just went through this with my floor standing Lowther speakers and my REL Strata II. I finally moved the REL to the other side of the room opposite my main speakers (to the right and rear of the listening seating) and fiddled with the controls and it works much better than when I had it in between the Lowthers.

I try to avoid using the LFE channel of home theatre equipment and run the sub via the main amp outputs into the speaker level inputs of the sub.
If you get a graphic EQ, you risk the wrath of the purists. Although a parametric EQ, like the Rives model, may not be a bad alternative to acoustic treatments.
Acoustic treatments are almost always a better alternative, if you can afford them. As for purists, I wonder if they would have any valid objections to EQing the subwoofer. The Rives is nice but for lots less there's the Onix R-DES and the soon-to-appear Velodyne SMS-1.

The Revel B15 has EQ built in. Works like a charm.
I know the Revel system and it's pretty good. The Velodyne EQ is much more configurable and easier to use.

Thanks for the responses. I wasn't planning on replacing the sub itself since I'm pretty happy with its sonic performance. I was just hoping to tame some of the imbalances that I hear which I feel are caused by the room. Its a finished attic with pitched ceilings and unfortunately I don't have the space to allow flexible placement of my equipment so the sub is sitting in a corner.

The Rives unit is a bit beyond what I was looking to spend but I'll look at the Onix R-DES. When is the Velodyne SMS-1 slated for release?

I've also heard a lot of talk about Behringer units. Is there a reason to avoid these or could these be used to accomplish what I'm looking to do.
All right, if you want to keep what you've got, then the first way to adress the placement issue is to put your sub where you intend to sit, and walk around the room and see where it sounds loudest - that's where you'll place it.

Will an EQ help? Sure - but unless you insist on one, see how the method described above works - it may be OK by itself.- If not, you can always use the method in conjunction with an EQ to do what the EQ'd subs do.