I am looking to get more bass out of my system

Mainsound, to answer your question about whether an equalizer will help: USUALLY it won't. An equalizer can only be used to cut peaks in the bass response. It can not be used to boost bass response.

If you were complaining of too much bass, or boomy bass, or one note bass - then an equalizer would help.

Insufficient bass is caused by a limitation in your amp, or a limitation of your speakers, or a problem with your room (e.g. if you are sitting in a null). Think about what would happen if you were to boost the bass. If your amp already struggles to deliver bass, boosting bass would cause it to clip. If it were a problem with your speakers, boosting bass would cause excessive cone movement and introduce breakup modes. If it were a problem with your room, no amount of boost will overcome the cancellation of bass at the listening position - whilst at the same time you are drawing more amplifier and making your speakers work harder.

HOWEVER, in your case, you are kind of implying that your subwoofers are not level matched to your main speakers - at least that is what I read into your statement "This system is capable of putting out the bass when the music is called to do so, but often I would like to hear a little more bass in general. There are no bass or treble controls".

If this were the case, then you need a device which would be able to level match the main speakers and the sub. You can either attenuate the main speakers, or boost signal to the sub. An equalizer should be able to do this, provided it is capable of amplifying the signal beyond unity gain. However, it would be better to use an active crossover.

AM is right that your amp must be up to the task of delivering more bass (ie power, current as needed) otherwise an equalizer will not help.

Its all relative though so sometimes cuts in other frequencies can produce results better than a boost in the ones of interest.

Like most things, it all depends.

One thing that always works to maximize bass is make sure your amp is capable of driving teh speakers to the max possible, not just to some minimum or slightly higher level.

Then, make sure your speaker placement and listening position is tuned as well.

After these two things first, then an equalizer becomes a decent option if needed.

And of course, speakers must be connected properly in phase or bass suffers.

Long time Chorus II owner here. I recently added a Schiit Lokius EQ and am very pleased with it. It has 6 bands of eq, plus XLR ins & outs. You can easily boost the bass, and adjust everything to your tastes. It is affordable and USA made. 

More subwoofers.

"raising the cutoff frequency of the sub" - This may help.

or 

Get a larger Sub.