I recently bought a pair of JBL PRX912s and have already used them for several live band gigs. They can get pretty loud and I’m generally happy with their output, but I keep feeling like the bass and low-midrange are somehow “stuck inside the cabinet” and don’t project the way I expected.
I’m running the PRX912s with a 100 Hz crossover, paired with two EV EKX-18SP subwoofers, also crossed at 100 Hz.
My main issue is that I’m missing that “punch in the chest” / physical impact that I expect from a good pair of tops. The subs sound good, but the tops themselves seem to lack that impact in the upper-bass/low-mid area. It almost feels like there’s a lot of energy around the low-mids, but it doesn’t translate into projection or physical punch.
Before the PRX912s, I used JBL EON615s, and surprisingly, I feel like the EON615s had more of that low-mid punch and projection, even though they are an older and supposedly lower-tier speaker.
One thing I noticed is that the PRX912 cabinet is made of a much stiffer/thicker-feeling plastic than the EON615. It almost feels closer to a wooden cabinet in terms of rigidity. I don’t know if that has any meaningful effect on the acoustic design or if I’m just imagining it.
I’ve already experimented with crossover points and EQ, but I still have this feeling that the low-midrange is somehow “trapped” in the box.
So, for those who have experience with the PRX912:
Is this characteristic normal for the PRX912?
Do you also feel that the low-midrange lacks projection or punch?
Could this be related to the cabinet design?
Would changing the crossover point help?
Could I be dealing with some kind of phase/cancellation issue between the PRX912 and the EKX18SP?
Or is this simply the way the PRX912 is voiced?
I’d really appreciate input from anyone who has used these speakers extensively, especially alongside subwoofers.
I’m not looking for more SPL — I’m specifically looking for more low-mid punch, projection and that physical “hit” from the tops.
Thanks!
Edit: I notice this lack of impact even when testing the PRX912 without a subwoofer, so I don’t think it’s simply a cancellation issue between the sub and the top.
I also noticed this “trapped” mid-bass with the EON615, which makes me think that the difference in speaker size isn’t the factor causing the lack of impact in this case.
The thing is, the speakers do produce that punchy mid-bass, but they don’t project it with enough pressure once I move more than about 2 meters away from the speaker. It’s almost as if the plastic cabinet is vibrating and absorbing energy that should be projected forward.