Customer Build: Father/Son Dual SDX12

We are starting a new blog category this week to showcase customer builds. If you build something with our drivers or kits, send us a write up and some pictures and you might get featured in our blog. This build comes from Bryan and his son out of Chicago, IL. They did a dual SDX12 ported design for his son's car. Bryan's comments on the build and photos are below:

My son has been tinkering with car stereo systems since he turned old enough to drive. This has provided a great foundation for several Dad/Son projects, our latest of which involved swapping a 15” Kicker L7 solo baric SPL sub for twin SDX12s in his 2015 Jetta GLI.

After modeling a few different possibilities (sealed, passive radiator, vented), we opted for vented to take advantage of the extra output. SDX subs model great in smallish enclosures no matter what the alignment is which makes car audio applications that much easier. In our model, a 3.6ft^3 box tuned to 29Hz with 1500 watts of input power satisfied our requirements for high output, low f3 and compact cabinet size while ensuring the drivers remained within safe operating range. We wired the subs down to a final impedance of 2-ohms. F3 comes in at 27Hz and F10 at 23Hz. At 1500 watts, the output is a very loud 122.5db (without cabin gain), and with extremely well-behaved driver excursion.

The cabinet construction was straight forward. We used plywood to keep total weight down since we were dealing with 92lbs of subwoofer goodness. The slot-port-loaded cabinet with double thick front baffle, a full window brace, partial shelf braces and a few CLD tiles weighed in at a respectable 49lbs, putting the final assembled subwoofer weight at 141lbs. Half-inch roundovers were applied to the slot port terminus and cabinet edges and we used roll-on DuraTex for the finish.

This dual SDX12 sub is INSANE! It walks all over the Kicker S15L7 in terms of SPL and especially in terms of SQ. The bass is super clean, tight yet deep and doesn’t distort as you ride the volume up. We’re using a 2400w RMS monoblock amp and the SDX drivers are laughing at us. My son has found bass nirvana. I can’t help but think what these drivers are capable of in my home theater, so we’re going to have to have another Dad/Son project soon!

Bryan K

Chicago, IL