I have been playing around with this on Tribble...
Here is the deal -- it does about 9 points less in damage than my Dual Heavy cannons...BUT -- it fires much more rapidly than they do. Here are the numbers based off of a LTG Tac in a Raptor with both dual heavy and quad cannons equipped, with energy skill maxxed, with and without CRF II activated:
Quad Cannons Numbers
With CRF II active: 924/1,681
Dual Heavy Cannons Numbers
With CRF II active: 2199/1,691 DPS
So, theorectically, the difference in sheer DPS numbers between the two are that Dual Heavies will tend to do about 9 points more damage than Quad cannons will.
So...what you have is a cannon that does less damage "per gun" than the dual heavy cannons do, but which fire twice as fast as the dual heavies do. The total loss of DPS, according to the tooltip rollover, is practically negligible...but on the other hand, there are two major benefits that Quad cannons have over Dual Heavies (in my opinion):
Benefit 1: The Disruptor proc.
Because the quad cannon fires more rapidly, the probability that the disruptor proc will be applied to the target is doubled...not only that, but because the proc stacks, you are achieving a max stack much more quickly, and in turn doing a lot more damage over time to your target than if you don't have them installed.
Benefit 2: Critical Hits
Statisticaly speaking...the more often a weapon fires in the same timespan as another weapon, the more often that weapon (the faster firing one) is likely to land a critical hit.
So...there is a silver lining. Interestingly...if they increase the "base" damage of quad cannons by about 5-10 points, I am fairly ceratin that it will out-DPS dual heavy cannons by a very significant margin.
However, having said that...I have the impression that you can only mount one of these...so with that consideration in mind, that it is essentially a unique type of weapon that a vessel can only mount one of...it does need a bit more "umph" to it than it currently has, I think.
My suggestion is to buff the damage either by increasing the level modifier, or adding points to the "base" damage...but even if they don't, Quad cannons may be a useful weapon to have. Alternatively, giving it a wider engagement cone -- maybe the same as a dual beam, for instance, would serve to up the damage potential of the weapon as well. Just a thought.
Thanks for the analysis. I acquired the Quad Cannon for Klingons on Tribble, but after noticing the DPS was less than my other DHCs, I never really used it much. I'll have to test it out again this evening.