ok so i have a friend who is a MAJOR audio enthusiast. hes had several systems in his car and is now sitting with a single 10 on 90 watts with a MASSIVE ported box thats pretty much all port.
I asked him what to do about my dissatisfaction with my twin 12" SX setup and i guess i might as well just show you what he said.
"Why not look at 1 sub with more port area? Makes the world of a difference with greater port area and increased efficiency. Look at a 15" with a medium Fs (28-38 hz), Qts below .45 or so and relatively low Vas. In ported boxes, x-max is one of the least important factors when determining output, so plan accordingly.
If you get that, you won't need much power in the right box to get what you want while retaining good sq. The aim is to get a high EPB (Fs/Qts) which would work great in a ported box. Amp should use subsonic filter a few hz above the tuning frequency."
so then i said isint more cone area better?
"Well, more cone area is always better but in my opinion, more port area drastically increases the amount of usable surface area from the driver, total front and back."
would i be better off redesigning my box for my pair of sx 12's to just have a massive (200 sqin) port or should i look into a single 15?
or should i do something completely different. before talking to him i was thinking about just cramming as much cone area as i can into an 8 cube sealed box.
im guessing since i got 3.2kw that the woofers aren't the reason why im not as loud as id like to be, but rather something wrong with my system design, even tho i have built 2 boxes for my subs. don't ask if they were good or bad because they were GREAT boxes extremely over built. but they were just normal ones with normal port areas and volumes relative to driver.
im not exactly sure he told me to do anything, except redesign the box.
how should i design it? ive already had 2 boxes substantially different and both are not loud enough so what now?
Daniel Says, i have never metered my car before but i would guess high 130's to low 140's, but i have never sat in a car that has been metered either so i have no frame of reference to put it with. There is not "real" car audio shops in Rochester, NY with meters or amp clamps, ive called all the places in the phone book and they all think im crazy.
this doesn't really apply to your situation but i feel like saying this...
i went from 2 12" Fi SSD's to 2 12" SI BM's (on a Nine.1) and i've currently got a single 15 TC3000 (on an M1) and it's soooo much better. it's louder, its cleaner, it gets lower. granted, all three setups are on different ends of the spectrum, but sometimes ya just need a change of pace.
but if you've got 2 12" SX's and they're not loud enough, i don't know what to tell you. Other than going to 2 15s or 3 12s, but i know you said that probably wouldn't fit, haha that would be plenty of bump for me bud, good luck though, i hope you find a setup you're content with
mark B, i hate living here honestly, once i graduate from college im out, movin to the south.
Im powering them with an Atomic 3000.1d
And cal thanks for the insight, it definitely applies to my situation i think.
Ive figured out what i want to do i think i have 3 options, lemme know what u guys think.
1)go with one really bad azz 15 in a ported box with a massive port like my friend suggested.
2)add a third sx 12 since i have the power. i could squeeze another in there but i wont be able to have more than 100 inches of port area
3)just make a box with a substantially larger port area for my pair of 12's.
i know that redesigning a box for my pair of 12's will be cheapest but im gonna have to do that any of the routes i go so i would really like to figure what will be BEST not most economical i already have 3 boxes sitting in my basement that i cant sell for sh1t.
i just can't seen to grasp 2-sx's on 3k doing high 30's.. 143-145 in a truck car should be about right.. i' know it's possible as I have help build a very similar system . was slightly less power. It hit 44's without breaking a sweat. What numbers are you looking to try to accomplish?
Lowdown, My car is very hard to get loud, others have had trouble getting loud as well with my type of car. only reason i can think of is it a large luxury sedan but i dont understand why Dodge Intrepids can get loud, only difference between my car and an intrepid is my trunk is smaller and i have more luxury features which dont mean anything in terms of car acoustics as well as fenders and bumpers.
you probably installed it into a small sedan or coupe, i doubt the system you installed was in as big of a car as my car.
i dont really care about numbers at all i just want loud music daily. also i have no frame of reference to determine what kind of numbers i would like since ive never sat in a metered car before, but i know there not high enough in my setup cuz i want more.
Lowndown, with username of hittin1 is me, Mark Brockman. As for the "wanting more" thing that is a terrible affliction that has plagued many on this forum.... Me included. lol So basiclly you might be hittin 43's and just want more, right? As for you car being hard to get loud, that really depends on your defination of loud.. So making a new box will be the answer? doubt it.. Different setup or something new may be your answer. If you dont have a "loud" reference point than I can't tell you if your setup in under preforming. sorry
but yea i suppose i may be in the 143 range but i doubt it cuz its only a little louder than my kappa perfects were and at a great loss in sq.
Im pretty sure i just need more woofers. im gonna bite the bullet and buy another sx 12 and make it fit.
or im gonna get 4 different 12's or 6 10's that will run in a net 6 cubes ported, im gonna call that my maximum enclosure size since that will end up being 10+ cubes externally with 100+ inches of port area tuned to 34 hz and after driver displacement.
i suppose i could compactly run 2 15's but i doubt that will be louder than 3 12's properly enclosed.
so Mark B you never said what kind of car you installed that system in, what is it? also how was the sub box and ports arranged in the vehicle?
you said earlier 58" inches of port .. you did not mention that was the PORT AREA ... and thats not enough for a 5 cubic foot box
minimum i'd run in 5 cubes is 80 square inches
i would turn the subs/port and fire them directly into the cabin..
build the box big enough to almost seal it off from the back of the trunk.. have the seat folded down and subs/port firing through
sub on each side and port the middle .. design the box so that whatever the width of the port is.. is would be that same dimension from the back of the box.. this way you have a straight port.. not one that looks like this
cisco, i got 3200 rms @ 1ohm how is that hardly enough for 3 12" sx's? plus it will be @ .66 ohms not 1 ohms so ill be able to squeeze a bit more juice out of it.
jack i think im gonna buy a third sx 12 run 6 cubes net 100 inches of port and call it a day. subs and port firing up. i dont wan to doa box likt that cuz ive done it before and i wond have room for ports if im running 3 12's in fact the subs would be touching just so they would fit. i only have 37x14.5 for the face of the box.
i thought that atomics were underrated. what do you think im really seeing rms @ 1 ohm.
even if its only 3k @ 1 ohm thats still enough plus at the .67 ohms it would be more like 3200 anyways. as long as the amp will remain stable @ .67 ohms which ive heard they can do as long as you have good electrical.
i'm saying after impedance and box rise you won't be seeing 3k daily. the best way i know how to put it is at 40 hz your amp does not produce the same power as 50hz. oscillating hertz results in oscillating power. when an amp is tested it is tested with a single tone, not music. real world power is a fraction of "rated" power.
200 amp alt. stock battery in the front and a hc2400 in the trunk. my voltage used to drop really bad but with the batt in the trunk i never drop below 13.6 volts.
I understand what your saying but thats the case for any amp. i used to power the pair with an American Bass xd2000 which was doing barely 2k rms and it was enough to bottoming them out on my 5 cube box above the tuning frequency.
i cant fit 7 cubes ported. and 15's would need more room than 7 cubes at least the sx's would.
i guess ill wait and see how much money i get for xmas and then ill decide what im gonna do. i figure 3 12's ported is the best i can do with my limited space or i could do 5 10's but i dont want to buy 5 new woofers cuz i know i wont have that much money.
3 12's on 3k+ is going to be LOUD. i say try what kevin said and then if its not loud enough do the 3rd 12. its cheaper to build a new box than it is for another SX
that setup i showed you was two RE SX 15"s on 3600rms.. would burp a 151.6dB @ 49hz on a TL out of the trunk
best bet to get trunk cars loudest is seal off the trunk away from the cabin having everything fire in.. the less volume you have the louder it is going to be.. if your filling up the trunk and cabin thats a lot of volume vs just the cabin
you could fire two 15s forward.. they would need to sit slightly back and you'd need to run two 6" aeros slightly outside of the box far enough to clear the subs excursion.. might have to cut the trunk opening a little bit to get the box in as i had to.. but you gotta make some kinda sacrifice
i ran my xxx firing up and port through the portion of my seat that folded down in my recent car.. i would not suggest firing a sub up in a trunk.. its not good unless you want to rebuild your rear deck under the window.. or port it
tck, 9 cubes externally isint 7 cubes net ported and 7 still aint enough for 2 15's. i can properly enclose 3 12's or i can cram 2 15's its only slightly more cone area but i would imagine a proper setup will always out perform a crammed one.
kevin ive had the 5 cube box in my car before sealed off from the trunk with towels just for a temporary setup and i like the way it sounds facing back better. its not louder but it sounds better. it wasnt out of phase either because i tried that.
depending on 15's 7 cubes is more than enough. i've owned 15's that bottomed out with a 3.7 cube box with extreme power. i had to change the design to 3 cubes. with that much power you can get away with a smaller box. whatever, 3 12's should bang.
so i sold my sx's and im getting a SINGLE 15" loaded BTL. my friend is gonna design me a high efficiency box possibly with a kerfed port. should bang pretty good on 3200 watts. he swears it will be better than my pair of 12's, well see tho.
prob not gonna have this done until the summer cuz i gotta go back to school on thw 18th and i may ot have time to build the box before then.
i dont have my car with me at school anyways so i wont be able to bump either way.
ill let you know when its all done. i post up pics of the build as well as a video with my super secret show off song that i guarantee none of you guys have ever heard. ill give you a hint tho, it makes all the ladies wet.
kevin its bigger cuz the port area is HUGE almost 3x the area of my old boxes so the external dimensions are quite a bit larger than for my 2 12's
on fi's web page it recommends 3-5 cubes for the btl thats why i was wondering.
i didnt want to build a new box for my 2 12's cuz ive already tried 3 boxes (one was under spec and i knew it wouldnt be good) and havent been happy.
its not a big deal i got a NEW loaded btl for 387 shipped and paypal. plus i just sold my used sx's for 350 to a local dude. and he wants a custom box for $120 so im makin out ok. as long as this btl dosnt disappoint me.
ok so i made my own plans for a box and im going to run them by my friend to see if he approves.
5 cubes net tuned to 34 hz with 120 inches of port area. is this a good design or should i change something.
box and port are going to be in upward slanted wall facing forward behind the rear seats which fold down. the box will be sealed off from the trunk so all the bass will stay in the cabin.
in case you guys forgot its for a fully loaded 15" btl on 3200 rms going into a 2000 chrysler 300m (dodge intrepid)
mark thats good... jack i have a question you said something about scoring 150s at 49 hrtz??? my question is is a trunk car supposed to be that high because i cant get my intrepid below 50 hrtz even with the port tuned to 37 hrtz.. sorry not tring to thread jack
not sure why your peaking so high even when your tuning is that low.. is it the same note your peaking at each time? if so tune 8hz lower than that note and that will be your spl setup.. build a plug to tune it down to 32-34hz for daily..
i still do not see how it would peak over 10hz higher than the tuned frequency.. you sure your tuning is accurate?
im not sure if my tuning is correct its the first box i built its two seperate boxs not one.. how do you build a plug?? and mark that should sound good
"ok so i made my own plans for a box and im going to run them by my friend to see if he approves.
5 cubes net tuned to 34 hz with 120 inches of port area. is this a good design or should i change something.
box and port are going to be in upward slanted wall facing forward behind the rear seats which fold down. the box will be sealed off from the trunk so all the bass will stay in the cabin.
in case you guys forgot its for a fully loaded 15" btl on 3200 rms going into a 2000 chrysler 300m (dodge intrepid)"
"ok so i made my own plans for a box and im going to run them by my friend to see if he approves.
5 cubes net tuned to 34 hz with 120 inches of port area. is this a good design or should i change something.
box and port are going to be in upward slanted wall facing forward behind the rear seats which fold down. the box will be sealed off from the trunk so all the bass will stay in the cabin.
in case you guys forgot its for a fully loaded 15" btl on 3200 rms going into a 2000 chrysler 300m (dodge intrepid)"
