custom subwoofer question

[ice_nyne]

Hey all,



I posted this question in the audio section of a Thunderbird forum I belong to and couldn`t get the answers I was looking for, so I thought I`d expand to this site where a wider cross-section of car drivers are.



I have a `96 Thunderbird, and I want to remove the arm rest in the middle of the back seat and replace it with a sub. I`d like to have the woofer firing into the car, and I don`t want to give up trunk space to a big box. I also am not using the back seat for anything, so it seems like the ideal location for putting a sub.



I found this picture that has a setup I`d like to duplicate:



http://www.tccoa.com/gallery/stereo/menste.jpg



It looks like an 8" sub with a tweeter above it. From the looks of it, it looks like the board the speakers are mounted to is upholstered in leather or vinyl that matches the leather interior.



What I`d like to know is, what size enclosure do you think is behind this? And what power range of amp do you think is driving this setup (assuming that the mids/highs are OEM)? Nobody on my Thunderbird site can ID the owner, and all they have to say is "oh, it`s easy to do, just cover it with a grill" and things like that. Duh. I need more info.



Sorry for the long post. It`s not a rant :argue It`s a call for help.

Thanks.



ice_nyne

[roller5435]

Hi there. The size of sub enclosure *and* the power rating of the amp all depend on the subwoofer you select. (In fact, so does the type of enclosure).



For smallest possible box (and better sound quality), you`d want to go with a sealed enclosure. I have 2 10" Infinity Perfect 10.1s in my trunk and for a sealed enclosure, they call for 0.66 cu ft of space.



My subs are also rated at 350watts RMS, so I chose an amp to match that rating (within reason).



The other thing to note, is that my subs are recommended to be "rear firing" only.. So I`m guessing that they wouldn`t be good for your application. I`m not an expert, so I don`t know why some subs are recommended to be pointed "away from the ears", but you need to look into that.



That ought to get you started. go to www.sounddomain.com and start researching...

[ice_nyne]

Okay, then let`s assume that the sub is a Rockford Fosgate Punch Z2408 -- 8" Sub w/ a freq response of 30 to 400 Hz, and a RMS of 100 Watts (200 peak). 4 Ohm impedance. Does that help things along?



ice_nyne

[hondaguy2582]

not really, you need the dimensions of the box for the sub. personally, i think a sealed applicaton of an 8"sub will only be around .6 or less and would fit perfectly in your tbird. I used to have a mercury cougar 1993 and i almost did the same project you did, but i decided i wanted to just be lazy and make a box for 2 12s instead of getting all custom fitted.

[hondaguy2582]

then again, you could also port the 8" sub as seen in that pic you posted. Youd still have enough space left over to port that sub!

[eldawg4100]

boy thats an awfule design LOL



first... it probably has a home 2-way crossover so the sub is playing up to 2k hz most likely



second... the tweeter is cheap junk that they use in cheap jensen home speakers i used to have.



third... what size port holes are those? lol



fourth... there goes his imaging, stereo sound out the window



it does look kinda cool and unique though... but you just wont get much bass with an 8 inch woofer firing right into the cabin...

[416 Auto]

LOL ...........Don`t follow the set up in the picture. That looks like a Fosgate 8" sub. That is CHEAP tweeter and those ports I bet make the sound worse.(if they are even real ports at that.



If you want to squeze some good bass out of a 8" use a dual voice coil and a monoblock amp. I`m not sure if you would know what this was and if not just ask and I`ll draw you up a picture and explain it for you. Also the best box and set up you want for bass is a S.B.R(where the woofer is right inside the box you can`t see it). Anyways ask any questions if you have em and I`ll try and help you out.





........................Clint

[ice_nyne]

Originally posted by Clinton

If you want to squeze some good bass out of a 8" use a dual voice coil and a monoblock amp. I`m not sure if you would know what this was and if not just ask and I`ll draw you up a picture and explain it for you. Also the best box and set up you want for bass is a S.B.R(where the woofer is right inside the box you can`t see it). Anyways ask any questions if you have em and I`ll try and help you out.



You`re right Clinton...I have absolutely no idea what you`re talking about? Explain it to me please.

[Steve @ Guru]

What sort of music do you listen to, and what are your listening preferences (deep, boomy bass; tight "rock" bass; jazz-like bass, etc)?



I`ve had lots of different stereo configurations, everything from a single 12" in a sealed box to 4-12" isobaric bandpass to 12-12`s in 3 different sealed boxes (that was a trip)....



The best cost:size:sound ratio configuration I ever had was one of my earliest set-ups. It was 2-12" Rockford Fosgate woofers (I know, I know, but I was a kid with limited $$ at the time) in a ported isobaric bandpass box. I ran them off a Soundstream Reference 500, and everyone was amazed by the sound (volume and quality). Even won me a local SQ contest. :)



Lot`s of options, we just need more info.

[ice_nyne]

Originally posted by geekysteve

What sort of music do you listen to, and what are your listening preferences (deep, boomy bass; tight "rock" bass; jazz-like bass, etc)?



Lot`s of options, we just need more info.



I actually listen to a lot of different types of music (hard rock/metal, alt. rock, rap, and DJ), so if there is a happy medium in there that I would be happy with, it would be a tighter bass. I read somewhere that for more punch with a smaller sub a sealed enclosure would be beneficial. Thoughts on that? I am committed to using an 8" sub and placing it as you see it in the picture in the first post. My primary motive is looks 1st, sound 2nd (which is assbackwards, I know). So knowing that I`ll be going with the 8" sub and the 3.5" tweeter (which I don`t HAVE to use BTW), I`m curious as to what size box will end up going behind it, and if the sub would be mounted on the short face of the box rather than the long one.



Also, from what I can tell about the backseat layout, the face of the box the sub gets mounted on would have to be angled a bit to match the angle of the backseat. (I think)

[chaotik]

If it were me, I would go with a Boston Acoustics Pro 8 sub. These subs sound awesome playing everything as long as you build the enclosure right. Also...it requires only 1/2 cu. ft. of airspace. And unlike other subs that "can be" put in a 1/2 cu.ft......Bostons rep told me that the optimum size enclosure for these is 1/2 cu.ft. I heard their demo car (audi TT) with 2 10" pros in it and it was unbelievable!! They can handle afew hundred watts (rms) and they should be put in a simple sealed box. You wont be disappointed.



Or you can go the other route like I have in my ex-cab Ranger. 2 12" Cerwin Vega Strokers (dvc) with a JBL 1200.1 amp pushing about 1300 watts into 1 ohm!!!:shocked

[meGrimlock]

First of all, don`t use the tweeter, let your rear speakers provide the rear fill.



Second, you need to figure out a budget. Spend about 50% of your budget on a quality amp. Don`t believe the pawn shop brands saying their amp puts out all 500 watts it says, its more like 50 watts. Invest in a good amp i.e. Alpine, MTX, Soundstream, older Kicker ZR or ZX series amps. Put about 30% of your budget aside for a good woofer; Kicker S8L7, JL 8W6, CDT 8" Minibox, Boston Pro 8. Use the rest of your budget for materials. If you are having a professional install the sub, you will have to sacrifice some of your budget from the other things to pay the extra installation cost.



You are looking at filling a rectangular shape, so the enclosure will be pretty simple. Make the enclosure as big as the space will allow (you can tune the size of your enclosure after you listen to it). It is much easier to fill the inside of an enclosure to make it smaller than to cut it apart to make it bigger. Stay with a sealed box, it will prove to be the easiest to build with your limited space. You might want to mount the woofer flush with the front of the enclosure so you can cover it with a grill so there isn`t too much eye candy for window shoppers.



Check out the car audio forums at www.sounddomain.com to get some ideas on equipment.

[ice_nyne]

So I should toss out the idea of putting ports on the subwoofer side in addition to ditching the tweeter?

[chaotik]

Yes....no tweeter...no ports. In all honesty..If you got an 8" sub that needed a port...you would have to get creative to make the port fit into such a small box!!! Just get a sub that requires a sealed enclosure...you will thank use later!!

[audio1der]

Agreed.