New Subwoofer Installed.

[ScottJackson]

I tell ya, there sure is a lot better audio stuff now than 10 years ago when I was last into that stuff. Seems there's a lot more heavy hitting type subs now and amps are just getting cheaper and cheaper. Too bad I don't care much for that stuff anymore. Anyway, cool thread so far. Would there have been much weight savings if the enclosure would have been made of fiberglass? I have always wanted to try building a big bandpass out of the trunk. I figure you can make a divider to separate the front of the trunk from the back, mount the sub in it, and have the back part of it be the sealed part of the enclosure. Then have a rectangular port tube come down and over the gas tank on the other side of the divider. I suppose it'd need a strong seal around the trunk lid and all the sheet metal would need reinforcing/dampening. But it wouldn't take up much trunk space to do it that way. Would that be feasible at all?

[nimbyfaygo]

I tell ya, there sure is a lot better audio stuff now than 10 years ago when I was last into that stuff. Seems there's a lot more heavy hitting type subs now and amps are just getting cheaper and cheaper. Too bad I don't care much for that stuff anymore. Anyway, cool thread so far. Would there have been much weight savings if the enclosure would have been made of fiberglass? I have always wanted to try building a big bandpass out of the trunk. I figure you can make a divider to separate the front of the trunk from the back, mount the sub in it, and have the back part of it be the sealed part of the enclosure. Then have a rectangular port tube come down and over the gas tank on the other side of the divider. I suppose it'd need a strong seal around the trunk lid and all the sheet metal would need reinforcing/dampening. But it wouldn't take up much trunk space to do it that way. Would that be feasible at all?

A fiberglass box would be more effective at saving space, but it would weigh about the same. The problem is, a fiberglass box would take about 10x as long to build and would cost around $300 for supplies. As for weight, I can take the box out of the trunk myself without too much trouble, so I'd guess and say that it weighs about 120lbs. The woofer is 53, and I used a little over 1 sheet of 3/4in MDF that weighs 60lbs per sheet.

Now you could build your trunk into a 4th order bandpass but there would be tons of problems with that. First it would be nearly impossible to measure the correct airspace. You could fill your entire trunk with packing peanuts, and then see how many cubic feet they occupied. That would be a pretty accurate way, just messy.

Bandpass's are very sensitive regarding airspace. Your tuning freq would change whenever you went shopping! LOL Your fuel tank would be Inside the ported chamber . Have you ever heard a speaker box that was made out of 1/4in plywood? Well thats probably close to the same way your trunk would sound. Unless you went crazy with dampening materials.

If you could over come all these problems you'd would have a very unique setup that would be able to house probably four 12's easy.

[heywier427]

ha the rattling is prob the same as mine! its the muffler heat shield or the cats. stainless steel screws baby!!!!

i had to tear my whole box apart to take off the rear bumper so mine is work in progress again!

i had to make panels to change my tail lights. which youll soon be blowing alot of! one on each side of the box. on hole to get in the box then one to get at the bulbs. i actually forgot about doing it untill my brothers said " how the hell are you going to change the taillights?" that would have been a btch

[96Qowner]

I'll be getting the alternator rewound at a local shop, and I'll be getting a second battery for rear. Its pretty insane the amount of voltage drop I'm getting, I'm being careful with the volume knob, only cranking it for short periods of time. I don't want to mess up any electronics by starving them.

Also can anyone tell me the factory amperage output for the stock alt on a 94? Its seems real low, especially at idle. I have a clamp on current gauge, but its at my dads house.

That was one of my concerns with your setup. The OEM alternator only supplies a little more juice than the car needs. It looks like you're gonna handle that with the rewind, but you might end up cooking it anyway with that kind of power draw!

Heheh, I gotta say, impressive install. I love what lots n lots of power does to audio.

1500 watts ... Egads, dude!

[qsiguy]

I'm glad to see someone doing something custom. Tire of seeing all the square pre-fab boxes sitting in the trunks with an amp screwed to the side of it.

Takes me back to my high school days. I'll have to dig up my old photos and scan a couple. I have a photo of when I was building a box for my full size Chevy Blazer for two 18" Fosgate woofers. I'm sitting inside the box with my head sticking out of one of the woofer holes. Those were the good old days. That box had an 8" port and was powered by a Rockford Fosgate Power 650 amp. Old school thump! Took up the whole area behind the back seat in a full size Blazer.produ

So does the soda can deflect sound waves or is it acting as a passive radiator

Come to think of it I have a Memphis 18" sub collecting dust in the garage, anyone else want their own seismic tremmor generator?

[nimbyfaygo]

Its a bit off topic, but here are some photos and videos of the audio system in my truck. http://www.minisinmotion.com/V...x.avih ... /V...g.avi


Modified by nimbyfaygo at 12:25 PM 2/16/2007

[Romeo5k]

well... this is tight.. i aint never seen some 18s before in a Q.. But thats playa..3 15s... i thought 3 being odd makes the the music kinda un-even... If it doest.. goood..I read up here about the back window being able to break, Although mine never broke, i believe you. Because there was once i was washing and rinsing off my car in the car wash and i had my music on like 12 or something .. which is kinda loud in my 93.... i started seeing water bubbles coming from around the rubber part that goes around the glass... sh*t scared me, i thought my back window was about to come off.I wanna know has anyone done anything different with that little middle console that is in the back in between those 2 6x9.... i had an additional 2 6x9 in there... but it sounded good, but looked tooo bootleg (non-factory).. If so.. show me pics... Ive got my 95 and my money, im debating on when to put it in the shop.. maybe this month or next month.. i have a valve cover leak thats real small but embarrasing. So i want that fixed. . Besides all that... im looking for another pioneer radio, going with 2 15s and 6.5 in front doors and like 6 tweeters and 3 amps and a whole lotta other stuff.. only thing thats gonna be paid for is getting the Battery and the Ground wire ran from battery to the trunk.. I tried to do that last time and couldnt.. it seems there is no were to run the battery to the inside of car. Last time they drilled a hole behind the glove box. and stuck it thru there...Keep beating up tha block.... I wish i could just go 4 15s... now thats playa!!!

[pdqwrx]

A fiberglass box would be more effective at saving space, but it would weigh about the same. The problem is, a fiberglass box would take about 10x as long to build and would cost around $300 for supplies. As for weight, I can take the box out of the trunk myself without too much trouble, so I'd guess and say that it weighs about 120lbs. The woofer is 53, and I used a little over 1 sheet of 3/4in MDF that weighs 60lbs per sheet.

Now you could build your trunk into a 4th order bandpass but there would be tons of problems with that. First it would be nearly impossible to measure the correct airspace. You could fill your entire trunk with packing peanuts, and then see how many cubic feet they occupied. That would be a pretty accurate way, just messy.

Bandpass's are very sensitive regarding airspace. Your tuning freq would change whenever you went shopping! LOL Your fuel tank would be Inside the ported chamber . Have you ever heard a speaker box that was made out of 1/4in plywood? Well thats probably close to the same way your trunk would sound. Unless you went crazy with dampening materials.

If you could over come all these problems you'd would have a very unique setup that would be able to house probably four 12's easy.

Technically you already have a fourth order enclosure (Actually the order changes with your windows being open or closed) But you are venting the woofers output into the trunk which vents (Or Loads) into the cabin through your "Vent" in the rear deck (Bandpass one) and then vents again if your windows are down to the outside world (Bandpass Two). It's part of what is called the "transfer function" of the car. You would do well to re-inforce the trunk lid with more then Dynamat. I would try to bet some 1/2 to 3/4 MDF attached to the trunk lid and every panel in the trunk that vibrates. When your trunk lid moves like you have described, it wastes the woofers energy both in moving the lid and in the pressure that could be leaking out of the seal. Great job so far, are you going to follow the bass up with some well designed kick panels and maybe some 6X9 or 8" mid bass drivers in the doors? I am also curious (You may have discussed this, not sure) about your battery and charging system. Are you upgrading besides the Bat cap? You might be able to get a higher output alternator off of a V8 truck application that was used for emergency type duty (Police, US Forest, etc etc).

Looks cool, you will have to post up some SPL numbers when you get a chance to run it.

CheersScott

[nimbyfaygo]

I'm probably never going to get the car metered for SPL. I didn't really build that system for SPL, the woofer isn't very effective in that enclosure. And the way the car is designed hinders the overall output of the sub, the transfer gain of the cabin is only apparent below 30hz and the subs direction causes cancellation. The Q45 isn't a good car to install a high powered system into. Its takes too much power to get loud bass from the trunk.I'm satisfied with it though. I'm probably not going to be doing any more audio upgrades other than electrical. I'm now reunited with my truck and I have a huge list of things to get done before show season starts up this year. Including redesigning the enclosure. I'm building a full wall for it, (15.5ft^3)and raising the tuning frequency to 49hz. I'm attempting to break 155db's while staying in the Street-Max class.