SubSam

Going to disagree with that. When I have time or when Scott has time we'll make a graph with what we found. Power is power..but what isn't being considered is your time value of a 'square' or 'clipped' wave over the cycle period. You are at the extremes of the wave form MUCH longer which induces a significant amount of more heat to build up...which..kills the sub. Seen there...and below in the following 3 images. Yes the 'power' is 'power' and 'watts' is 'watts'...but you are not considering it over a given period of time where the coil is literally standing still burning and then immediately slamming in reverse and standing there and burning until it gets slammed forward by the fets. It is like trying to change gears without pushing in the clutch while traveling 70mph forward and 70mph rearword. Clipping...induces a SHIT ton more heat over this period of time..the heat and the coil bouncing off of the switching frequency of the output transistors..causes it to melt. Lots of people probably think an amplifier pumps a dc current back and forth at a given variable frequency. It's not like that at all. These people belong on the team that built that mechanical MTX woofer (tards). One thing in terms of amplifier topology I should have mentioned is the nature of digital processing, which is evident in the majority of most amplifiers these days. The beauty of the digital design is that any waveform can be broken down into pieces, almost unlimited times, and processed "piece by piece" if you will, which also becomes one of the design flaws. The square waveform above, if looking at the two 'corners' of the wave, is basically a dc current running hard through the coil. Obviously not good for the vc. What separates good amplifier processing from bad is a frequency sensitive regulator. The INPUT signal, if square (100%), can still be processed as a normal sine. In square, out round. If you are talking strictly input signal, then I'm not on the same page. With a poor amp (with analog or simplistic digital topology), at very low power (less than thermal limit), a dc current through the vc won't kill it, depending on the ratios I suppose, and may lead to mechanical failure, but can't really be a definite "coil killer". Especially since apparently Fi uses great materials for their winds. But when you start to add extra power and square waves then you got definite problems. Lesson: Buy good amps dammit, that HiFonics POS is only gonna get you laughed at. Pm me and I will turn your HiFonics to a Stetsom, for a price

I'm not talking signal, I'm talking amplifier output. I am agreeing with you that "clipped" (inappropriate term but anywho) signals can not break a woofer, without excess power, which could tear apart a coil without a clipped signal. And I won't venture further into woofers, as I don't know much about them except the obvious; I was talking strictly amplifier failure, I'm not into building woofers, but amps, mmhmmm But I really can't dumb it down enough, if anybody really cares buy an dual analog/digital amplification textbook, might wanna brush up on fields and waves if ur calc is rusty... pay attention to signal propagation under distortion, which is one of the easiest scenarios to model mathematically (obviously), and watch what happens when you compare the power OUTPUT of the amplifier with a high uncertainty (non linearity), to what it should look like. And model the phase plot while ur at it, its ugly to say the least. I can hopefully post a graphic when I get home from work, basically the amplification can fail in a way that the signal is totally non-sinal, and the slower the recovery of the electronics, the greater the currents through each component (Just like low Hz LRC circuits). Current doubles, heat dissipation quadruples. That's some V=IR stuff right there. I'm just trying to explain how his amplifier failed, so nobody blames the sub. my N2 is my new baby.

Props to Fi for making quality coils, nobody says the copper (or whatever) has to burn before it melts stuff, if its good quality. That's a melted 60 amp fuse holder with the fuse in tact that ran my power inverter and a minifridge for an hour... what temp does that thermoset plastic melt at? What M5 was getting at is that maybe you all don't even know what clipping even means beyond a square waveform in your mind's eye, but really the subject at hand is distortion. Before I continue I will say that 99.99% of the time if you blow a woofer, its the amps fault, whether by receiving inadequate power support or having incorrectly adjusted the levels or you flat out misaligned your amp to your woofer. So, back to clipping: Amps are rated at a given total harmonic distortion at a corresponding load, ie 2000 watts at 1 ohm WITH .1% THD. The same amp, at higher distortion but same load, may look like 3150 watts at one ohm with 10% THD. Now distortion is basically any imperfection in the sinal waveform, typically 'squaring'. The more its non sinal, the higher the THD. Obviously in this case you probably had not only a gain level issue but some voltage drop and a resulting distorted mess, pumping ugly chunks of way overpowered sloppy signals through the vc until the glue quit. Now are you comparing the sound of two neo BtLs on 1500 each to the sound of one gen 2@3000watts? I ran my gen 2 at 2400 watts, now my neo BtL at 2230, almost identical boxes and the neo is very very similar, tho a different car. Comes alive at much lower volume, kick drum has extra oomph (slightly), but I can respect your opinion. Mine differs, however.

im always in for some new builds

Re reporting from another world Magazine full of bullets you can be my covergirl Ness got the weed roll it thicker than a southern girl Strong arm rap like a ni**a did a hundred curls It's not the worst thing weezy put out, the bassline travels, I don't mind the lyrics... now that he spent 8 months in prison and has to be sober for three years his rhymes are sure to decline, tho 6 foot 7 foot is kinda ok also (in my opinion) Anyway I can count on Wayne for a beat

1. Of course cameras, especially phone cameras, make subwoofers sound terrible. There's a million videos out there to prove it. Even the best systems can sound like crap on video. 2. The new BtL N2 at 300 watts is a joke, especially considering most N2s out there are still virgin tight out the box, of course she isn't moving. I think, however, that the new BtL comes alive at a slightly lower power than the gen 2. Proof? Video: half volume, low boost (maybe 1100 watts TOPS) on a variable bassline (Lil Wayne 'I am not a human being')

Thanks it is a 15 but its not quite 150 from the trunk... I am happy with 147, when I upgrade to around 4k watts maybe I can close in on 150, tho I think I am limited to around 148.5 no matter what I try. You should definitely get an N2 (or a couple) for your car; join the exclusive Neo Fi Club

Well I got it in non-inverted... I really wish I left myself more clearance to get it in there, it really is difficult to maneuver a 40+ lb woofer little by little with your fingers Theres 13" of clearance and a 15" woofer in there for petes sake! Anyways on to the pics: See how I left myself a dandy ol' problem? But there she is, after a monster of a struggle... Now I can watch her dance for me And just to make sure nothing came loose during the flip it is good practice to check your connections beforehand: Thats still a .8 across the voice coils... fresh as a daisie Ill keep ya'll posted on the meter runs tomorrow

So I have the results of the back seat test, which I suppose I should have predicted: With the gains set where I want them and the volume mostly as loud as I would turn it up at this point (@28 on alpine cda-105) , its putting up a 145.3 on a 30Hz sine with the back seat off, 145.8 at 70 Hz, and 146.9 at 35Hz. I put the seat back on, and metered about the same (both down .2dB) at 30 and 35, but 144.6 at 70 Hz. Other data I took (back seat off/on): 25Hz (139.4/138.5), 40Hz (145.8/145.8), 50Hz (145.4/145.1), 70Hz (145.8/144.6), 80Hz (143.1/143.0), and 90Hz (135.9/135.4). Basically it all went down (seats not stiff enough) and was way down at higher freq (same at 40, -1.2 at 70). It's not a huge difference, but I'm hoping for a gain. Key word: hoping. I have a strong recollection of a 146 number with my gen 2 at 30Hz and 144s at 50Hz, but in my grand prix on a different amp and the box was definitely tuned lower. Hard to compare, I would be really stretched to say anything in terms of a comparison; they are both awesome woofers. I have an inkling that my negative 6th order effect is due to the woofer being inverted and consuming volume in that mounting location. My project for tonight is to take it out, flip it around, and then meter it again tomorrow, hopefully with dB's on the plus side. If not, oh well, I'm not really expecting it to work lol. Anyways that's the fun I've been having. More soon, maybe even pictures of it non inverted

Rdo: resistively dampened operation... its a lot of fun, back from the atlas days it didn't catch on quickly, but some normal dvc woofers work well in an Rdo setup, such as the jl w7 sealed. The potentiometer just let's you vary the QTS very delicately, makes for a lot of room for "soundplay"

so whenever you have to install a big 50+ lb woofer by yourself in a trunk you strain the crap out of your fingers and usually need a helping hand. I remember installing my gen 2 and taking a nap right after from being exhauated. The reason im bringing this up is the square (rectangular whatever) motor of the N2 really makes it nice to handle solo: I still have to clean up a bit and put my backseat back in but i at least got to drive around a bit to give it a listen. Initial impressions, compared to the gen 2 in a similar enclosure are just that it comes alive at a lower volume than my gen 2. Its obviously still virgin tight so ill have to loosen it up a bit. Nice to have it up and running tho.

Thanks all for the compliments and friend requests. About the pm regarding the wire covers, i did have better pictures of the sides: They are made from quarter inch mdf and fitted onto a small central pin. The fit is so tight i could have pressure fitted them, but they would likely fall out when the BtL gets going... Cheers and good luck with your install. Mimicry is the best form of flattery, im glad to help.

You competing in KY MECA? I think I know a dude out of bowling green in s2, cant say for sure if he is competing still but good luck anyways... Ive heard about a few guys with a lot of skill, but also a lot about ugly winning installs. Dont be the guy with the ugly system lol, tho I think those 4500s and N2s will turn some heads. You should do an inverted wall lol nobody does walls ass out

Actually im in CT just a finnish citizen with a green card, but the power hx2 is sold already, I just have to finish the install in my friends civic. Three of the remaining four punch hx2s are going into a single and double woofer install, all three are still brand new in the box. I have one more, and one coming out of my fiances old jeep liberty be replaced by a Fi Q, so I have two up for grabs. I know the one I have out now has 2.1 ohm dvc still, ive really babied it, the other I dont know for sure. If you or anyone else wants a rockin punch hx2 (rfd2112) send me a pm we can work something out I would love to see these woofers in a good home

I too use it for everything! I will redesign a box like 100 times on solidworks until I get it just right... The software really makes all design processes so fast and time efficient (if ur good at it), and it is an awesome skill to put on your resume. Everyone needs a CAD tech

Hell yea thats what I like to see merry christmas indeed

thanks to all for the nice words! @TRP yea I look super young... I still get carded for cigarettes and ill get carded for beer probably till im 40 lol @aimone yea its a punch hx2 im a big fan of the hx2s, both punch and power. Ive been installing them for a decade or more, still have a half dozen 12s laying around. I think I will go lay them out and lay in the middle and flap my arms untill I make a woofer angel lol Its christmas eve after all lol

M5 is totally right... T-lines shouldnt even be folded once, let alone multiple times. Also you need a tapered cross section with respect to the woofer cone area. If you have a quarter wave, thats one thing, a t-line is the most difficult enclosure to design and fabricate, almost impossible in cars even with 8s. Either way if it sounds good then enjoy it

Merry xmas to all. Im full of holiday cheer so long as I have my new BtL bumpin

Build is up on the logs section, about 97% complete: cheers, happy holidays

I was pretty damn excited to wire it up… A big hell yes goes out to Fi Car Audio for making great woofers including this new BtL, I know it was a pain to make this sub for me, but I appreciate it. Then five minutes later: The most anxious part in the build… I had measured the side-to-side distance to be just capable of clearing the woofer. Lets just say a piece of paper can slide in on one side but not the other Been waiting to predrill the woofer mounting holes so I can carpet the visible portions of this side. The fact that the baffle was so closely measured side-to-side meant the woofer was automatically lined up in that regard. I cut the mounting hole exactly so that the outer edge of the woofer would be a half inch off the floor of the trunk, so once I shimmed the woofer up with a piece of .5” MDF it was just about lifting the magnet into place with some lumber I had laying around, which in turn brought the woofer flush. I did a poor job leveling the magnet, I guess its hard while looking upside down and backwards at it but its fine. The hole was cut 14 and 3/16 inches, and the woofer sits in there perfectly inverted. With that magnet, how can I not invert it?? You may have seen this picture already, but that’s the only one I snapped before I put the back seat in. I have a few things to tweak in there in the coming weeks, so I will probably wire that up in a prettier fashion. Honestly the woofer has itty bitty clamp terminals, real tough to get full copper contact with one 8ga input let alone two. Its in, its tight, im not touching it for now Putting my back seat in was a real pain… Its so closely fitted again that the back of the seat actually flexes a bit against the box when I bolt it down, but I wanted that so the seat sits in place tightly and doesn’t get pummeled around by the BtL. I used some adhesive rubber strips, big chunks of closed cell foam, and some carpeted pieces of MDF to keep an airtight seal between the woofer’s “chamber” and the seat. I doubt the seat is rigid enough to allow for a 6th order effect from the seat blow through, but who knows. I don’t live in the most crime filled area, but around here if somebody peeked in and saw a monster 15” BtL they would probably steal my car. The woofer was bolted in with Torx screws and my father-in-laws 50lb torque drill, into a half inch of fiberglass. Nobody could budge those screws with any cordless drill, let alone a screw driver And that’s how it has to stay for now, at least until after xmas. I left enough room for mounting a second monoblock, I hope to upgrade to a pair of Rockford bdCPs. The box sounds good so far as it should, very much a similar overall design scheme compared to my previous BtL enclosure (visible next to my name over there <<<<), time will tell if it really bangs like the gen 2. Door panels are also soon to come, though my highs are well suited to the current configuration, I just want a little more flare than the stealth look this car has now. Thanks for reading, feel free to post comments. Enjoy your holidays, relax like my dog here, just toasting in front of the wood stove

And more glass It just occurred to me I suck at taking pictures Now theres some serious glass on the other side of the baffle as well. See the spots where I left the baffle mount curved how the resin can be built up and cloth sunken in to make little solid fiberglass shunts for braces… basically along with the screws theres fiberglass wedging it in from all sides. Its solid for a single layer baffle. Time to fiberglass the box out of the trunk and build the amp rack. Test fitting the amp housing size. Of course I fiberglassed the whole rack without test fitting it, only to find out it didn’t fit no matter how I tried, so I cut in half and decided to build onto the right half by building the other half separately and joining them later on. I like a heavy-duty felt like material for making certain molds that require strength. The felt really absorbs the resin well, two coats of resin with some scraps of fiberglass and sawdust in it and the felt becomes stiff as a board. A couple layers of cloth and resin over that and its good to go. Amp rack progress The deer had to come check out my rack drying out in the backyard. There were deer everywhere for a few days, including one bigass buck that sent me running inside like a little girl. Usually deer are scared as hell, this guy stared right at me and headed my way. I was outta there! With the amp rack attached, I could begin making the skirt to flush the rack to the trunk. Again I used the felt and a few secret tricks to get the shape just right, and laid the resin down heavy. More resin… amp rack makes a good beverage holder while its not housing the wattage. Fiberglassing some cloth in there Some more cloth… thing is hard as nails I love dynaglass… its really a step where you can correct so many minor imperfections with one well performed sweep of the mud knife. You can build up areas and fill gaps way bigger than bondo, but it’s a real pain to sand down if you lay it on too thick. Sand it down, fill it back up… x3 Same stuff Some grey primer shows all the little lumps and divets you can fix with sanding/body filler, if you did a good job with the dynaglass this should all take about an hour tops. Then its on to carpet. This is about the time I realized my spare tire needed about a quarter inch more clearance to get in and out easily, so I had to halt progress on the trunk until I feel I can shave down the bottom of the rack and put down some more dynaglass and finish the bottom portion of the carpeting. The false floor will be easy enough to build. So earlier I mentioned the battery isolator. By mounting it in the trunk, inside the battery chamber, and wiring the 4ch to the T-Distro ’above’ it, the isolator keeps the auxiliary and primary batteries separately but adequately charged and the amps are fed by two different charge sources. Time to close up the battery compartment Lots of wires ran, the amps are going into their pre-bolted positions on half inch MDF mounts. This allows me to run some RCAs and other wires beneath the amps, while also giving the amps some more breathing room. So flush and so clean. Some aluminum battery terminals I cut out in a jiffy. Triangles hot and round for ground. You can get more conductivity from copper or brass, but these will do. Long as theyre smooth. Building out the battery door. Now that’s the shape Close Gets a little repetitive… but its worth it to get a flush fit After a quick check on the collective battery/alternator performance, I wired up the relay and powered up the amps. Wires did a vanishing act. ----THEN I WAITED… sat around for a long time with nothing personal to work on, but built up some car audio business in the meantime. In the back of my mind Im just thinking BtL, BtL, BtL... I really wish I held onto my gen 2, or one of my spare Fi Q's, but its ok I still had my other vehicles to bump around in. Then on Monday the UPS guy gave me a nice surprise

Anybody want a build log?

Im really liking this woofer. Again when I compare it to the gen 2, I am comparing two excellent drivers, so the majority of the differences are minimal percentage wise, but the N2 really is an improvement so far in my opinion. Any bass note has an extra sort of 'oomph' to it. Its like the neo magnets are so strong they hold the cone in place and oscillate the whole car back and forth Its still loosening up... Im having a great time helping speed up the process

Hey matthub I got kappa 6x9s in the rear too lol its like we have too much in common for equipment... Im running two kinetic hc800s with an orbital exide under the hood, not xs batts but I will prob go xs later on when I build a new monoblock pair. Anyways heres a reposted shot of my N2 and I love it