midnightE39

ive got one Fi SSD15 on about 1200 rms in a ported box at 37 hz in the turnk of my 525i. i saw some alpine subs on sale online, the new Type-E's for real cheap, I was thinking about buying those 4 12s, or 3 JL audio 13 inch W1s, and sealing them up in a box. what do you think the overall difference in soudn would be? i'm assuming a louder (more surface area, same power) and cleaner (sealed) sound?

Which is absolutely normal in an E39. Btw, the stock mids have absolutely no balls. The car will come alive with something real.I'm sorry, what does RTA'd mean? also, M5///, i would suspect it were the car, but my old setup with subs and port back i did not have any such cancellation issue. Also after further deliberation I have found the the airspace of the inside of the box is not equal to the VAS of my speaker, I am suspecting this and orientation (sub up/port back) to be the culprit and i plan to build a box at least another half cubic foot larger with the sub and port back.

This has my vote for comment of the day. This disclaimer could probably prevent quite a few hurt feelings...Actually, I am a club DJ. I am fully aware of what he was referring to, i'm a newbie to this forum, and I know more than most people I meet about car audio.My last setup was 2x Kicker 07CVR12's in a 3.5 cube box port tuned @ 40hz. I had none of these cancellation issues, I'd wanted an Fi sub for a while and decided to try them out with an SSD15, ported in 3 cubes tuned @ 37 hz port back sub up. I believe that the 60-70hz dropoff (where it is most noticeable ~12db) is a result of cancellation from the secondary waves bouncing off the rear of the trunk (near the tail lights) and hitting the waves coming off of the cone at just the right timing, there are only about 4 inches of clearance above the subwoofer cone, the roof of the trunk lined with Q-mat and i'm not sure how much is necessary, my rear deck is mostly metal and simply punching holes in it is out of the question. I have only a decent sized ski hole to vent into the cabin, which was fine with the kicker 12's. Note that when i open my trunk and watch the subwoofer and box, 2 things happen; the subwoofer itself vibrates and moves the box around slightly (wasting energy that needs to be sound) and while the trunk is open, the sub seems to play all the frequencies i give it just fine, So i am assuming my sub up port back orientation is causing cancellation issues in that top bass range. I'd also like to note that it seems that right after 70 hz the response picks right back up again, i cross my sub and mids at 100hz and it plays everything just fine up to that point. Even higher if i turn the LPF up a bit, i have my subsonic on about 32hz, phase @ 0, no bass boost, my gains are set correctly. If i multiply the tuning freqency of the box by 2, does that give me the point where the subwoofer cone is moving the most? Sit in the back seat and see if that is indeed the problem. If this is the case then making a big change in drivers wouldn't sole the problem, or try turning the box around. I have repositioned the box towards the tail end of the trunk, port facing the cabin. I noticed a slightly better frequency response in the problem area, while overall SPL declined.

Not really. My PHDs play down to 50Hz with authority. It's install-dependent. Before you go and upgrade the drivers themselves, focus on install techniques. Are all the air gaps in the door sealed up? Have you applied a ring of CCF (sponge rubber works fine and can be found at THD) to mate the front of the driver to the door card? These two steps alone will dramatically improve your sub-100Hz performance out of the front stage. I'm on stock components with only 5.25 midbass drivers, it's a BMW so i belive they are alpine speakers, as was the whole stock CD player, because they actually have a good soundstage and such clarity i'm hesitant to even upgrade them, though i was considering a new pair of some components for the front stage, maybe some fosgates or JL on a 4 channel, and just put some cheap kenwood coaxials in the rear for fill. But that will come, right now I need to get this SSD15 sounding right, as of right now they only outperform the 2 CVR 12s on the lows. I believe it should do better with 1000watts than than 2 kicker 12s on about 600 RMS. Was i mislead when someone told me that larger cones can play the upper bass just fine as long as their motor's are good enough?

This has my vote for comment of the day. This disclaimer could probably prevent quite a few hurt feelings... Actually, I am a club DJ. I am fully aware of what he was referring to, i'm a newbie to this forum, and I know more than most people I meet about car audio. My last setup was 2x Kicker 07CVR12's in a 3.5 cube box port tuned @ 40hz. I had none of these cancellation issues, I'd wanted an Fi sub for a while and decided to try them out with an SSD15, ported in 3 cubes tuned @ 37 hz port back sub up. I believe that the 60-70hz dropoff (where it is most noticeable ~12db) is a result of cancellation from the secondary waves bouncing off the rear of the trunk (near the tail lights) and hitting the waves coming off of the cone at just the right timing, there are only about 4 inches of clearance above the subwoofer cone, the roof of the trunk lined with Q-mat and i'm not sure how much is necessary, my rear deck is mostly metal and simply punching holes in it is out of the question. I have only a decent sized ski hole to vent into the cabin, which was fine with the kicker 12's. Note that when i open my trunk and watch the subwoofer and box, 2 things happen; the subwoofer itself vibrates and moves the box around slightly (wasting energy that needs to be sound) and while the trunk is open, the sub seems to play all the frequencies i give it just fine, So i am assuming my sub up port back orientation is causing cancellation issues in that top bass range. I'd also like to note that it seems that right after 70 hz the response picks right back up again, i cross my sub and mids at 100hz and it plays everything just fine up to that point. Even higher if i turn the LPF up a bit, i have my subsonic on about 32hz, phase @ 0, no bass boost, my gains are set correctly. If i multiply the tuning freqency of the box by 2, does that give me the point where the subwoofer cone is moving the most?

is that the case? because under 100hz is Sub-bass, meant for a sub-woofer, correct me if i am wrong?

the problem is that ive not got enough 55-85hz

thanks for the input. yes my SSD does need a new box and ive been designing a new one when i came across the sale. ///M5 I have one ported 15, vs 4 sealed 12s at around the same power.

Fi SSD 15 standard options has a qts of .41 which IIRC isn't good for a sealed enclosure. I'm going to have a guy who advertises custom box builds on craiglist locally build me a new enclosure just under 4 cubes, port and sub back at an angle so the 15 will fit vertically (well, diagonally). He told me if i don't hear a big improvement or am otherwise unsatisfied he'll only charge me for the wood. just hoping port and sub back fixes the cancellation issue.

So i've got an Fi SSD15 in a 3 cube box @ 37hz. sounds really awesome and clean on the lows, up to about 55hz. there seems to be a massive hole in the bass response between 60-70hz. I have the LPF at around 110hz because despite what i hear most people cross their subs at, mine just gets louder and louder and plays clean up to that spot. there's no apparent cancellation when i open the trunk, the woofer seems to play all the way from 30-100hz effortlessly and with a fairly transient response. the thing is that its in a sub UP port back configuration, and there only about 3-4 inches of clearance between the subwoofer cone and the roof of the trunk. I had tried moving the sub box all the way to the back (near taillights) of the trunk and i noticed that it solved a lot of the cancellation issues. at the cost of low end extension and overall SPL went down greatly. I'm thinking i need a new box, with the port and subwoofer on the same plane. but my trunk doesn't offer me enough vertical space to mount the 15 without a slant on its face. 2001 bmw 525i. I would have put this in Fabrication forum but I wasnt sure the problem is entirely related to the box itself, but i think it may be. i tested this with tone sweeps from youtube played through AUX on my smartphone. i've played with my phase knob and no matter where i set it, it doesnt seem to change anything. So my question is: is sub up port back in a trunk typically not a good setup? it seems like the sound waves from the port are hitting the ones on the woofer cone at just the right timing to cancel out this one frequency zone. thinking about building it port back sub back with the face at a 45 degree angle and maybe an aero port on the side? or possibly through the ski hole of the car? im almost certain its just cancellation.

i thought the whole point of CEA ratings were so that manufacturers couldn't just crank up the voltage to an unrealistically high level that you'd never have in your car (or something to that effect) and then rate their amplifier's output from there? i thought it meant that if it had that certification then it meant the amp made rated power at 13.8 volts or some specific value. Do elaborate.

I've been running a Hifonics GLX1400.1D on my SSD15 for almost 3 months and it does a great job. CEA-2006 certified, never gets hot, nice features. and just under $200. If there's something i don't know about amps that cost twice as much for the same rated power, someone fill me in. I get the impression that many companies like Soundqubed simply jack up their prices for the name after they've established themselves, I was planning on buying the AQ1200D at $170 or so a while back and I remember that they jacked up the price by like $90 one day for no apparent reason, listed specs stayed the same. But I'm a newbie to the scene so what do I know? I just figured get something with plenty of headroom, is CEA-2006 certified, and since i'd seen loads of people running Hifonics amps on Fi subs, i figured i'd just roll the dice so long as it wasnt the H-Fi line. I'm satisfied.

I'm certain now after moving my box around that it's an issue of cancellation. Sub up port back in a trunk is apparently not a good orientation. Of course there is always cancellation caused by something, but with my old setup (2 CVR 12's ported @ 40hz sub and port on the same side) there was very little noticeable cancellation when I had them faced straight forward port facing the ski hole; with the sub and port to the back, they were boomier and seemed less responsive, but overall there wasn't a huge difference either way. I'm just hoping that when I rebuild, aiming the sub back and port back, it solves the issue. I wanted to face the port towards the ski hole but not seal it up to it, but the general consensus here was that that was not a good idea either. What i'd like to try is sub forward, facing the ski hole with the port back. without sealing off the trunk. there are openings in my rear deck to allow some of the bass into the cabin but they aren't very big, but i noticed more "high" bass when the old setup had the woofers and port facing the ski hole, and they were about halfway back inside the trunk because the box was too wide to go all the way back, however it was 2 woofers so they were in such a position that they might have "bounced" bass off the back of the seats and i was mostly hearing what was coming from the port. with my single woofer setup, sitting cone forward at the ski hole and port to the back, i'd bet i get better transient response perhaps at the cost of a little low end spl. is there any way to predict what sort of cancellation different orientations inside a given trunk space could create?

how's port forward or to either side?didnt try side, sup up port forward had the best transient response in my trunk but i lost a ton of spl especially on the bottom end.this is with the enclosure all the way back towards the tail lights http://www.soundsolutionsaudio.com/forum/topic/60149-i-did-something-wrong-with-my-box-ssd15/?p=1017262 I'm considering doing this without the bandpass part, just turning the port at the sky hole to around 34-37hz, any objections? Not sure how my driver would perform in a bandpass but Fi said don't seal it up without high qts option.

What about just adding an 8 inch midbass driver facing right into the ski hole playing 60 - 350 Hz, on a mono amp ? Or 2 channel in tri mode with the 2 in the front doors on it?

Sealing the sub and port into the cabin would be an option depending on what it would entail. My seats do not fold down, there is ski hole behind the arm rest, and I was considering a new box with a partially external port extending through the ski hole slightly. Totally separating the 2 waves, would that likely be a solution? I'd mount inverse for wiring reasons, which would look cool too. What would I have to do to seal up the port to to the ski hole?

i experience the same thing right at 65hz on my Fi SSD15. I believe it's because my subwoofer is firing up and the port is firing back, creating cancellation in the trunk because of the size of this particular wavelength and the fact that there's only about 3 or 4 inches of clearance between the woofer cone and the trunk roof. i moved the box all the way to the back of the trunk near the tail lights and the cancellation problems improved quite a bit, but i lost a lot of SPL. what is your sub/port orientation?

I'm just saying that the difference in price is so miniscule that I can't see anybody NOT just saving up for an SSD if they're thinking about an X.

I'm also curious, if I configure an X12 with the BP power option, it's more expensive than a standard SSD12. So what's the better option? Fully loaded X or standard SSD?

Ok I moved the box all the way back towards the taillights, there's enough room for air to escape and its a 43 sq inch port, but I've read some site posted on here that this way the secondary waves "bounce" back towards the cabin much closer in phase with the waves being produced by the cone. the cancellation has been reduced a great bit, though i think the orientation is to blame for that and beacause of it i shouldnt be able to get the response perfect. will be building a new box with both woofer and vent on the same plane. May even attempt that bandpass style box that was demonstrated if it would actually provide a smoother transient response. but i want my subwoofer visible somewhere I like how it looks

So I built a 3 cube box (net) tuned to 31 hz for a new, Fi SSD15 with standard options. port area is 34 in^2 sub up, port back. slot port, 11.5h x 3w x 24d box is 13h x 32w x 20d. 11 sq inches of port per cubic foot of the internal enclosure volume. I'm getting great low end, but the output begins to drop sharply at 55hz, being hardly noticeable at 65hz. I did a tone sweep and the output drops off sharply between 55-65hz, picks back up a little bit in the 70's until it begins to roll off around 90hz where i have my crossover set. My old pair of kicker cvr 12's hit this range wonderfully tuned at 40hz in the same car. I think my box and port are the wrong sizes. ive watched my subwoofer as it attempts to play this range, I've been told i just may be experiencing an exaggerated low end, but I don't think this is the case, as I have observed the subwoofer attempt to play notes in these trouble zones and it doesn't seem to move right when it tries. I have extensively read over these forums and I cannot seem to find anyone with any similar problems. I've used winISD and it tells me that my response curve should be covering these areas, unless I didn't use the software correctly. I've wondered that since this problem zone is at double the tuning frequency of the enclosure where the woofer cone should be moving most of all (as opposed to at vent tuning, where it moves least? tell me if i'm wrong) Would this indicate that the pressure inside the box at this frequency range is preventing the cone from moving the way that it should be? because that's what it looks and sounds like is happening. how does an L shaped port affect tuning? does this make sense? could the wrong port size relative to the box size create enough back pressure on the woofer cone to cancel out frequencies? some insight would be appreciated. EDIT: just realized, the port is 3 inches wide all the way through, it extends 4 inches into an L shape, but the width is only 3 inches throughout, leaving only 3 inches from the back of the box. Is this too small of a space for the air to try to push through? I figured I was supposed to keep the port width consistent all the way through.

im thinking maybe there wont be as much cancellation if the box is all the way at the back (next to tail lights) port facing either toward the cab or against the wall? the only opening is the ski hole in the back seat, but ive been thinking about modifying the rear deck, creating an opening in the back of it maybe.

kicker's were sub back and port back, i went sub up on the 15 because it was the easiest way to fit it in there. the general consensus on this forum that led to me to choose the 15 was that bigger is always better if you have space for the box, after my recent changes to the box; increasing the port volume up to roughly 14.5 sq inch per internal cubic ft up from 11 and thereby lowering internal net volume down to the 3 cubes minimum everything seems to sound better. considering that i may need to build a larger box with a slant to face the sub back. when i really crank up the volume i noticed that box itself actually jumps around the trunk, moving an inch or so in one direction or another. im thinking that is indicative of too little internal volume. there's no noticeable distortion in the cabin, but the subwoofer cone is moving with so much force under high power and it makes a little bit of rattling noise, though cant tell if its port noise, lead slap, or just other things in the trunk rattling or the woofer itself distorting slightly. then again, i've never had such a powerful subwoofer, only a pair of 2 kicker comp12s and CVR12s. might just not be used to seeing one move so much. i'm told Fi subs are tough as nails and i would have to be feeding it in excess of 1100 watts to truly put it into a danger zone. with standard options that is. my subsonic is set around 33hz. lpf is at 100hz~, i set the gain with the remote from the amp, just cranked it up with that until i reached a point where more gain didn't yield more SPL. so i think i have it set to the right sensitivity, which would be 4 volts for my head unit. phase knob i have left alone at 0, no bass boost. amp never gets hot, hifonics glx 1400.1d. 4 gauge wire, 150a ANL fuse connected to an 1100 amp battery. only about 2.5 ft between power cable and amp, 1.5ft from amp to negative terminal. TL;DR : sounding much better with larger port area and higher 37hz tuning. suspecting box volume is a bit too small, suspecting that sub up port back is causing some cancellation issues. should i try putting the box at the back of the trunk near the headlights and facing the port towards the cabin?

no i did not. 2012 SSD 15 standard options. i just opened up the old box today and made the port 3.75 wide and tuned to 36hz and it definitely sounds better than it did. now i have 43 sq inches of port area and exactly 3 cubes of internal volume. it is definitely hitting the 60-70hz range much better, but its still lacking some of the output that the 2 CVR12s had in that range. though it does blow them away below 50 hz in both SQ and SPL. I still feel like something isn't right. i've created a crude illustration in mspaint of what my frequency response would look like on a spectrum analyzer. keep in mind that with my old setup, there was no such dropoff in the middle, it just didnt get much lower than 40hz with any authority. http://www.mediafire.com/view/myfiles/#

do you mean walling off, or do you mean just building a box with the port aimed forward through the ski hole? also it used to hit this range well with 2 kicker cvr 12s @ 40hz i do think my box isn't allowing enough excursion after watching it during a tone sweep.