( joash, I think the op is not using a subwoofer and was expecting the bass rock from JBL ES-90's...)
If that's the case, I think you are in one of the following two cases.
First, maybe you expected too much from your ES-90's. ES-90 is designed to pump out a wide range of frequencies, not just bass. Looking at the spec, it covers 36Hz to 40KHz, which is a full range. And the 8-inch woofers covers everything below 500Hz looking at the crossovers. 500Hz and lower are a lot of mid-bass and low-bass to cover, and obviously it is not going to spend all of its time to pump out "punch" bass like a subwoofer, which normally covers only 80Hz and lower. I hope I don't come around as too lectury(?), but speakers move back and forth to create the sound, and the lower the bass the more it has to move. So, your 8-inch woofers (even though there are two) cannot spend all its time to produce really low bass. That's why there is a subwoofer even for speakers like ES-90 with dual 8-inch woofers. By giving all the low bass work to the sub, ES-90 can focus on producing sound from 80Hz to 500Hz, which is plenty of work for any music. For my home office setup, which is stereo playing music 100% of the time, I still use a dedicated sub because it produces a lot clearer sound with each speaker working on narrow range of frequencies rather than trying to do everything. And to add one more point, even with a subwoofer, you are not supposed to hear the sub while playing music. What I mean is, the subwoofer should pump out the right amount of bass to complement your fronts in a stereo mode, not overpower the fronts. The ideal music listening setup is when you feel like all the sound are coming from your fronts. Bass is not something you should be able to locate. If you can, it is way too high...
The second case is what probably makes your experience worse. If you like to have real "punchy" bass, I assume that you used to have the bass turned up a little too much in your previous setup. There is nothing wrong with it, but it is just not what the sound engineers intended. Put back your old Promedia speakers, and get a SPL meter from RadioShack to measure your sub sound level. You can do it by outputting the test tone from your 1018. If bass level is higher than your front speakers, your bass level is too high. If this is the case, your ES-90 won't be able to give the bass you want. 36Hz is pretty low, but it is just not designed to rock like some car woofers. It is good at producing the accurate sound with a balance between high and low frequencies. So, if you want boomy bass, you definitely need a dedicated sub in your setup.
I've owned various models of old JBL E series (equivalent to new ES series), and they are indeed excellent speakers. I would not add a sub to E-50 fronts that have 8-inch woofers as long as I want to listen to music as it is recorded. For music, they are fine because music doesn't go as low as some movie tracks with explosions, etc. But, if you want to beef up the bass, you need a sub. ES-90's just won't be able to do it.
Since you already have the Promedia sub, you can hook it up to your 1080, or get a nicer sub. I definitely think though a much better subwoofer is more fitting to your setup, which already has really nice ES-90 speakers for your fronts. Hsu, Velodyne, Bic, SVS, and Dayton are a few names you might want to look into.
People have different tastes of sound, so there is nothing wrong with wanting more bass. However, I would recommend listening to music just with your ES-90's and see if you can get used to it, because that's actually what the musician wanted you to hear... ES-90's are more than capable of giving you that.
Just my 2 cents...