Festival rig

Hey guys!
Me and my friends are once again this year going to a festival. It is Roskilde festival. There's live music, but a lot of camps build their own PA systems too. We as well had a PA system last year, but this year, we wanna go bigger than last year. Of course we want it to be as loud as possible and sound as good as possible. What can you guys recommend. Sub builds, tops, amplifiers etc. We have 3 JB PWX 18 600 drivers. When we're going to be outside with no electricity, the amplifiers have to be car amplifiers running on 12 V.

The PWX 18 600 is a pretty all round driver. The bigger the cabinet, the more you can expect from it, so how much space can it take up? Also what tops did you use previously?

Best regards

Cubo

Hey Cubo
We had two DW Audio 2520. These are danish made speakers and aren't produced or sold anymore, so not a lot of information on them. Each speaker has 2x15" drivers and a tweeter, and produces 450 w RMS, 900 w peak.
For the amplifier we used the Pioneer GM-D8604.
The space is currently not an issue, because we'll buy a new rig. The one we used last year measured 2x1 meters (6 feet 6 inches x 3 feet 3 inches)

Well, 2 x 15" tops have decent sensitivity but especially the cheaper versions have either compromised mid or high frequency response. Personally it's not the first thing I would replace unless your missing something, like output or quality of the sound. To get higher sensitivity you're looking at a horn loaded top. To get higher quality overall you could look at a different compression driver + crossover.

First thing I would look at is replacing the subs to boost output in the 40 - 100 Hz region. As you were using the PW's in reflex cabinets, many cabinets will have improved sensitivity ratings. From 40 Hz and up, Cubo 18 will be 3 - 5 dB more efficient in a cabinet of approximately the same size (250 litre a piece). If you want to go really loud the 186 horn (450 litre a piece) or WSX horn (570 litre a piece) might be better choice.

Best regards

Cubo

Thanks Cubo
I think we might end up building 3 cubo 18 with the drivers we have. Would 19 mdf be alright? And would you recommend the magnet inside or outside the chamber?

I just so happen to have the construction plans for 19 mm thickness (in cm's), and finally Imperial construction plans in fractions, if you think in cm's is too easy. Please send an e-mail to questionsaboutcubo at gmail dot com for the plan.

Magnet in or out? I would start with the magnet on the outside, if you feel you need more SPL, I would turn the magnet inside.

Best regards

Cubo

P.S. I would place the bass cabinets as close to the ground as possible, with the tweeter of the tops as high as possible (centre of horn at 2 - 2.2 mtr would be optimal).