Last time on the daily driver, we tried out a selection of rolling stock, all to simply end up back with the stock rim set. Now we aim to discuss a bit about the car’s in-car entertainment system. Truthfully, we have been upgrading it bit by bit over several months now. We will be dishing more info about our ICE setup in the next installment. But for now, it’s all about that bass, no treble.
We started upgrading our car audio by adding some bass to the car. The thought was that having a subwoofer would make a big difference to an otherwise bog standard sound system. It was, but things escalated from there, bringing us at this juncture, where we ended up cobbling up a sub from a broken bass tube, plumbing materials, and cannibalism.
Precap
We begun by buying a used 10″ active subwoofer set and having it wired to the car. Not satisfied by the output, we turned up the bass and ended up burning the pre-amp. We converted it to a passive set and bought a powerful yet cheap Class D amplifier. Then burned up the sub. Then we got another set of subs, a pair of 12-inchers. We modified and reupholstered the enclosure. It thumped pretty hard but didn’t sound that good.
We ended up removing the subwoofers after a while, enjoying the system better without them. We were on the lookout for yet another subwoofer option that wouldn’t break the bank. After all, it’s Christmas, the festive season that drains wallets.
And then, we found a ported enclosure for sale at a Facebook selling group. It used to be a Pioneer TS-WX304T bass tube, but it had no subwoofer and a missing vent tube. The appeal for us was that it was round and presentable, we could make it work with parts on hand and existing know-how, was probably sized to be a proper ported enclosure by smart Japanese people, and that it was priced fairly and located relatively nearby. We grabbed it the day we first saw it.
Assembly
We gathered what we needed to make the round enclosure work. The major issue that needed some thought and creative trawling was the fabrication of the enclosure’s vent. Despite becoming a pain to do, it allowed us to tune the box at a frequency where it will sound the best. We could have just sealed up the hole, but we really wanted to check out what a ported box would sound like.
What would the design be for a proper vent? The first thing to do was to figure out what frequency we wanted to tune the box for. Cursory Google searches did not reveal what specific frequency we should tune at. But, we felt that there was a consensus as to what range we can target, somewhere around 28-35hz.
Then we used an online port calculator to generate the length of pipe needed given enclosure volume, port diameter and target frequency. This is what we used, but there are others to be found if you use Google. The box volume was approximately 1.45 cubic feet. We decided on using a 3″ round port because that’s what Pioneer recommends for the subwoofer the tube would come with. We arbitrarily decided at 30hz as the target frequency. Crunching the relevant numbers gave us 12.4 inches as the length of the port.
Next, building the port. The vent hole of the tube was 4.5″ in diameter. We needed to figure out how to secure a 3″ pipe to this grossly oversized hole. Thankfully, the only hardware store open on New Year’s Eve had a 4″-to-3″ PVC pipe reducer. The inner diameter will secure the matching black 3″ pipe we bought with the reducer. The outer diameter is slightly larger than the enclosure vent hole. We had to sand the hole to make the reducer fit.
Sans power tools, we used a bit of elbow grease to slowly and excruciatingly increase the size of the hole with some 80-grit sand paper. We first held it by hand, and later with a metal pipe and zip ties. It took us two and a half hours to make the hole large enough for the reducer to be a snug fit. A total pain in the buttockal area, but we needed the exercise.
The next step was to attach the 3″ pipe to the reducer. We cut the appropriate length with a hacksaw, daubed PVC cement on one end of the pipe, and plugged the sucker into the reducer. They got stuck on pretty quickly. We then attached some plastic chicken wire mesh on the other end, and filled the enclosure with some polyfill.
Polyfill has the effect of increasing the enclosure volume. That messes our calculations up as we didn’t factor its effect on frequency. Holding the other factors constant, increasing enclosure volume, whether physically or via polyfill, would lower the design frequency of the box. We think the box is now tuned at around 27-28hz. Still close to the ballpark range, so should still work fine.
After the polyfill, we fastened the subwoofer in place. We couldn’t use the Pioneer grille, and instead went with the grille from the old setup. We also used the old screws, which were at as-new condition. The bass tube was now done!
As we’re not car audio experts, we don’t know to adequately understand and therefore convey whether our new bass tube is good or not. But from listening to it so far, we think we can say that is a definite improvement over the previous setup. It thumps just as hard as when the car had two 12″ subs in a sealed enclosure when we play some familiar bass-laden tracks.
The marked difference, however, is the way the bass sounds. It’s much richer than the former setup, a perfect match with the hip-hop and R&B that we like to play. Acoustic tracks feel much richer as well. There was some dissapointment on certain rock tracks, as some low frequency drum sounds seemed to be out of pace with the rest of the music, but we think a small tweak in the Time Correction feature of our head unit got that squared.
The cavernous rear compartment of the Carens accommodates the round subwoofer tube fine. Straps need to be procured to hold the enclosure in place, instead of having random junk at the back act as a chock. As a wagon style body, the Carens has awesome cabin gain effect that really does justice to the new bass setup.
Hoping you guys would be waiting the next installment, where we discuss the rest of the car audio system. As of this writing, its not actually done yet. But the bargain hunting part of it is done. Once it’s presentable, ya’ll will read about it soon. 🙂