Rockford Fosgate T212D4 Car Subwoofer

This sub was one of two installed in a 2004 Trailblazer as part of a full stereo install. These subs were fed by one ZAPCO 500.1 per sub, with all amps receiving signals from a Pioneer DEH-P9600MP. The rest of the speakers in the truck were Morels fed by a ZAPCO 1000.4 with 1 farad caps upstream of all three amps. All cabling was handled StreetWires ZN6 and UC12 patches and speaker wire. The entire vehicle was lined with about 210 square feet of Dynamat prior to building and component install. Although it is still hotly debated on virtually every board on-line, I have now done in excess of fifteen Dynamat/Brown Bread installs and every one of my clients have come back to crow endlessly about the difference.

From the sound damping to the components, box building, fiberglass, and wire runs, the entire install took about a week as most of the work was done after hours at the clients shop. Normally I don’t like to mix and match so many components, but as an auto performance shop owner he gets deals and trades all over the place, so when he came to me for the install (interestingly, he was still doing performance work on one of my cars….) all the products had already been purchased. I figure he’s saved me thousands, it’s the least I could do for him, well, that and he is going to fab a new custom downpipe for me free of charge.



First Impressions


These subs are ridiculously heavy, that is most likely the first thing one will notice as you try to pull it from the box. The second thing that stands out is that they are gargantuan, especially how deep they sit, even when compared to similarly deep subs like the Infinity VQ series subs. Although I didn’t set them on a scale it is fair to say these things weigh upwards of 30 pounds. For those that lift weights, think of dropping a few 35lb. discs on a sled, yeah, they’re heavy. Even before I hooked them up, I knew these things were going to bump something fierce. I have to be honest, I am not a fan of Rockford products, I think, with the exception of the very low end, they are overpriced, overhyped, and at times, excessively bling, but this unit has grown on me.

Aside from the sheer mass of these things, they do look good. The design is clean and almost architectural with the cast basket stretching gracefully over the motor structure. The reality is that one will see only about 20 percent of these once installed in a traditional manner. These were installed in a top mount configuration with extended vents. The surrounds are unique as well, looking more like a squashed catenary curve rather than the traditional half hoop and is surprisingly thick with very little give. The cone itself is an aluminum parabolic style piece devoid of the traditional convex dust cap sporting a dimpled edge. The aluminum surface has a brushed look except for the word POWER is polished across the face, There is also a small “T2” logo at the edge of the cone. The connections are disappointing in that they are tantamount to spring clips. The connection seems solid enough, but considering what these can retail for, the fact that they do not feature binding posts is appalling.



Performance


These subs were mounted in ported boxes with an interior volume of just short of 1.6 cubic feet. For aesthetic reasons the vents actually extends from the box rather than being internal. I can’t really say how this may or may not have affected the sound, it just is what it is. These subs are receiving 500wpc from each of the amps and that seems to be fine for the purpose, though it is clear they could take double that RMS if managed properly. Although I have seen more, the overall cone travel is fairly impressive in and of itself, but the surround seems to do more than adequately to help keep things in line. There was no break in period with these subs or the mains, once they were installed I got right to tuning and evaluation.

Initially I set levels conservatively and was impressed by even the low level punch, but there did seem to be some sloppiness. Once I got the mains tuned I started in on the sub and cranked it almost immediately. Using test material from Chemical Brothers, Lance Cashion, Craig Burkenhoeffer, Tupac, Cannibal Ox, Paul Okenfold and a bunch of house and trip hop the client provided I was quickly made aware that these subs weren’t screwing around. The punch was hard and focused, even if the accuracy wasn’t what I would call top notch. It seemed that no matter how hard I pushed them, they wouldn’t flinch. I never brought them to the point of heavy distortion, primarily because after several hours of fixing bugs, some connections and overall tuning, but more because my ears needed a break.

As time went on, and certainly since the install when I have ridden in the vehicle I believe that the subs have matured somewhat and sound, dare I say, improved somewhat in accuracy, especially in long low tones, though their punch remains fairly unchanged, still skull crushing at high SPLs. It isn’t just punch that makes a sub, it is also the fluidity that they are capable of and even on subtle passages from the Dances With Wolves soundtrack, I was impressed with how they could just fill the vehicle with warmth. I am a strong fan of sealed enclosure for fidelity’s sake, but after a brief phone call with Rockford previous to building the boxes, it was made clear to me that they simply were not intended for sealed enclosures and that “Rockford recommends” they be loaded into ported enclosures



The Brass Tacks


The numbers can give you a good idea of what a sub can do, but only listening can give a full picture. To some degree one could say the same of an amp, sure the manufacturer might say 1000wpc, but the 25amp fuse says more. Simply looking at this sub will tell you it can do what you need, but the numbers give you the guidelines and buying info you need to see if this unit is best for your needs. So, here they are…..

Frequency response ~ 28Hz-250Hz (per the spec sheet, some websites contradict this, but I believe the free air low is 33Hz, just FYI)
Voice coils ~ Dual 4” 4ohm
Former ~Aluminum
Cone ~ Aluminum
Basket ~ Cast Aluminum
Surround ~ Rubber
Power Handling RMS ~ up to 1000wpc total
Power Handling Peak ~ up to 2000wpc total



Final Thoughts


At Almost $700, this sub is clearly not for everyone. It can be had for as little as $450 delivered, but even then, it is still rather pricey for most folks. If you are about to drop $2000 or more on a car stereo, this may be your answer, even if just a single unit though this is qualified by assuming that two grand would be spent appropriately. This particular install exceeded $6000 at retail prices, though that was most likely not the case here. This is not to suggest one could not use this sub in a low dollar enclosure, it just depends on balance and how you weight your needs. Personally, I am very I am very impressed with this sub. Although I think its MSRP is too high, it is imminently capable and screams to have a kilowatt or more pounded through it. I am quite impressed with the punch, the depth, and the ability to take big power (all things being equal in this case). If you need heavy punch and have the dollars to power it, I strongly recommend this unit., but I will say that at less than the price, Treo, JBL, and Infinity hold up quite well.