SPL & SQ / Fabrication

The Effects of Cabin Gain in Car Audio Have you ever wondered why car audio systems can have so much bass as compared to a home stereo system? The reason has to do with space. Your home has a lot of it and your car audio system doesn't. Because there is so little space in a car the bass notes (which are long waves) build up inside the passenger area. To calculate the length of a sound wave you divide the speed of sound (in feet per second) by the frequency. At sea level, the speed of sound is approximately 1,127 ft/sec. For example, a 40 Hz note has a wavelength of approximately 28 ft (at sea level). (speed of sound)/(frequency) = wavelength OR (1,127 ft/sec)/(40Hz) = 28.…

Im looking to get a good SQ setup. Ive narrowed my options to the SSA Icon 12 or a Fi Q 12. Whichever one I get will be powered by a Cadence TXA-1000D amp. I cant decide on which one, hopefully somebody here will be able to help me decide. I listen to hard rock/metal almost exclusively and I drive a 97 2 dr Exploder. So, which has the best SQ with the most output? Thanks, Mo Also, if I get the BP option on the Fi Q and still just run that same amp would it make a difference?

I've heard of people blocking off the rear cabin vents ( behind the vent caps) to gain loudness in the cabin anyone here dine it or does anyone know if it works because with my system turned up if you walk to the back you can here a farting noise coming out and also you can feel the air coming out

My dash is pretty much completed. It's built to be very flat from a-pillar to a-pillar with no erratic or uncontrollable reflections. I have some ensolite ready to apply but need to consider an aesthetically pleasing way of covering it. I have considered a few different materials.... Vinyl - I would love to wrap it in vinyl, but that would do nothing as far as taming reflections. Suede - Not bad for managing reflections and certain kinds are permeable, but good suede is expensive and looks like crap as soon as it's touched. Tweed - Permeable and manages reflections well, but ugly as all sin, in my opinion. Any thoughts on a good covering material?

Know that my 270A alternator has been ordered I'll be ordering a second FI BL 15 for my car. I was wanting to get you thought on this parameters

never designed a ported box before so feel free to give any critisism/help for an xcon 10" net box volume 1.37 cubes port length 31.05" diameter: 1.75" if anyone is so inclined feel free to double check calculations and such as ive never done this before and might have done something wrong all info should be in pics bellow

I've decided to try a ported enclosure for my sa-10 just for kicks. I'm thinking 1.0ft^3 tuned to around 33hz. I'm not set on 33hz, it's somewhat of a guess as to what may sound good - I'm going for sq more than spl and listen to all genres so I need it to give me the accurate punch of rock as well as the lows in rap. My box is limited to a size of 8"d x 13h x 33"w The sub will pretty much be right up against the rear shelf of the car behind the passenger seats in a porsche 911 so I was thinking it would be better to go with a side firing aeroport over a rectangular port. My box would measure roughly 8"d x 12.5"h x 31"w, making it 1.12ft^3 after sub displacement, this wou…

If I do my setup the way I'm thinkin, looks like I can only fit tens. Max diemensions is 34 w X 15 h, I'm pretty certain. I've got the rest of my truck bed in regards to length. I've got a few ideas.. Lemme explain this. First off, these are overhead view of how the box would be. There not to spec or anything, just some ideas. Its not the right diemensions or anythin.. just some ideas how I could fit a few 10s. Would fire into my window. The first one, top left, is a sealed box, kinda based on a clamshell on its side. second one has four subs, and a port in the middle. Bottom is just a ported box with two tens firing into the window (not sure if you could fit two tens an…

so im pretty new to going to competitions and competting my subs. i was just wondering if only one has any tips or tricks i could use to help gain dbs?? anything will help i just dont want to go in this competition that is coming up and not know something to help me.. i drive a two door tahoe i have 4 12's ppi pcx subs and i was wondering if i folded down my back seat and moved my subs closer to the front would that help (probably a dumd question but you never know until you ask)

OK tell me if this looks correct. TD=time delay A=distance in feet from ear 1132ft/sec=speed of sound 1000=ms TD=(A/1132)*1000 Left=2.2ft 1.94ms=(2.2/1132)1000 Right=4.6ft 4.06ms=(4.6/1132)1000 4.06-1.94=2.12 TD Does this look correct? I found this formula on ECA, I am having problems finding other formulas on the topic.

i have noticed a desterbing trend on every forum... when someone post about : Loud SPL or anything bigger than a 10" sub the SQ sharks come out in force and rain on our good time. but GOD forbidd i rant on one of there rich boy toys *cough JL audio cough* can we have a lil less nagging from the SQ bunch PLEASE??? how would they like it if i/we go into there threads and NON STOP SLAMM them for having over priced underpowered subs & whatever ??? cant we all just accept that everyone has a different point of view as to what sounds good

The vehicle is an '89 mustang (hatch). Im wanting to keep the enclosure at right around 10 cubes to keep my imp rise at about one ohm but want a different port placement. it is possible that this may just be a wall but im looking for the best gains, what should i do? the build is with four FI SSd 12's thanks guise.

so i think i wanna make some new boxes for my 18" BTL's they sound great in the boxes there in right now but i think i can gain a little more output with some new better made boxes. right now there in a 2000 dodge caravan. the boxes are 8.756 cubes tuned around 32-33hz sub up port up. i have been told by a friend that also runs 2 15" btls in a caravan that sub up port up does not really gain the maximum potential out of the cabin. so i was thinking about making the new boxes sub up port back. what do you guys think about differant setups like sub up port back sub up port side sub back port up which one do yall think would be the best? and can any one explain what port off…

POLYURETHANE FOAM the reason im writeing about foam when im talking about fiberglass, is that you can make mold's out of thing's. just fiberglass over it then get some acetone and it will eat the foam and keep your fiberglass mold. they have 2pt. polyurethane foam that is equal mixing self-rising foam. most 2pt. will start foaming around 45 second's after you mix the two, and will go for a few minute's after. now it will expand around 25-30 time's it's liquid form. unlike polyester foam, polyurethane foam it's compatible wth both polyester resin and epoxy resin. (which mean's you can paint the resin on and it wont evaparate) now they have polyurethane foam sheet's allread…

so im planning on building a wall in my civic soon just want some tips... how do i calculate the box when theirs curves i have to go around... also should i have the port on the top or the bottom of the wall ?? also does each sub need its own chamber ?? i have 2 18s so does the wall need a piece in the middle to seperate the subs ?

Hey guys! I did a bit of reasearch but couldn't find a good topic about this. What do you guys reccomend for some good box building tips for the best box possible? Not like designs so much (Although if you wanted to post set-ups such as like...Explorer, sub up port back (as an example) that might be helpful to some), but things to do in the box. Things like: Rounding the port edges to flairs 45 degree angles in the corners for standing waves placing the subwoofer so its at the back of the port length where to add braces so that turbulence is minimized (or using rod threads or your favorites) those were a few I could think of as example and I'm not even sure if they're al…

im makeing this post for ppl trying to use fiberglass on there install's. this will help you understand how and what to use to make the job easyer. i will have more later and hopefully have a step by step so you can see it at work.... so here we go... the material's you might see is fiberglass this came's in many form's such as chop mat, cloth, fleece, speaker grill cloth and speaker carpet. next is the resin again came's in many form's, polyester and epoxy. these are the most used in the car audio world. other thing's you'll see is PVA, mold wax, MDF, bondo ect ect.... (and a few time's steel mesh, but i never used it.) ok now im goin to talk about resin. the resin we mo…

Hey all, newb here! I just ordered a 12" BTL, so I have about 3 weeks to plan my build, with the biggest project being the box. I heard a while ago that in an SUV, a setup in which the subwoofer is pointing up, and the port is pointing back is optimal (straight from Memphis Audio), but yesterday I found a page showing tests that the subwoofer pointing back yielded higher SPL levels versus the same sub pointing up or even to the side. Which is correct? Does anyone have any personal experience with SUVs that can shed some light for me? I will probably be building the box to Fi's cut sheet dimensions, just need to know whether to put the sub on top, with the port facing…

someone posted up a link to a SMdesigns thread that had a whole bunch of tips and help for building a good transmission line box. Whoever posted this up please let me know, as i am having trouble searching for it. Much thanks to anyone who has this link. Mike.

I'm looking for someone whos got a TL anywhere in wisconsin or near illinois border.

hey all been looking to make a t-line for a large scale project but wanted to start off with something small in case it doesn't turn out so well. now i no the port area has to be the same as the subs cone area, and the length is the speed of sound divided by the fs of the sub then divided again by four. but ive been told some have a common chamber and some don't and also im trying to figure out how to tune it or can you only tune it to the fs of the sub? any help would be greatly appreciated and ill let you guys know how it turns out once im done thanks mike E

my question is im trying to make a box for 2 18" btls dimentions are 49"L x 24"T x 27"D here are some rough sketches from paint how should i go about bracing it i know that i need to(or do i?) since im planing on running them on 2 SAZ-3000D and i will doublebaffle the top where the speakers will be mounted would simply corner bracing like in this pic be enuff and also placing a small block of mdf on 1 or both sides of the port to support the middle of the box

how much port do i need for a 9.0cf box is 120'' of port to much port---like 16.5'' tall 6.5'' wide 16''deep i just dont wont to much port any help would be nice

So tonight at work I was discussing my upcoming sub build with a few guys. One of the master debaters argured that stuffing a sealed box with poly-fil was recommended and the other said it was a joke. Yes? No? Why? Thanks.

I built my box fits good....but the damn thing is to tall lol so i got to rip it aprt cut the rabbits and fix it pisses me off took 2 weeks to make and i fudgeed up but owell itsmy first box