midnightE39

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.

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?

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.

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?