Nihilistan

I'm going to make up a jig for making a baffle that will replace the rear trunk passthrough. This can be attached a rear-mount (ie. subwoofer box) sitting in the trunk for those who are interested in mounting something where the hatch used to be. Not taking "orders" right now, just trying to get an idea of the level of interest.

If you're interested, please lemme know what "type" you'd be interested in:

Kicker S8L7 subwoofer baffle - Custom baffle to fit the sqare sub. Just attach to your box in the trunk for a "stealth" installation.

Flush-Mount Kicker S8L7 subwoofer baffle - Same as other baffle, 'cept the speaker mount will be recessed so the front of the driver will be flush with baffle.

Blank - No holes. For those custom projects including mounting other small diameter (< 9") drivers.

Note, right now I'm not sure if the kicker sub can be ported onto the same baffle. I'll be taking some more measurements and will post an update. You always would have the option of porting the box through the deck or into the trunk.

Material used will be MDF... prolly 3/4" thick double-stacked. All baffles will be marked with center lines as well as where the trunk opens up to aid mounting. I'll also throw in all trunk passthrough and related dimensions/diagrams to help if you're going to use for custom work.

-- Nihil

guji2

I'm interested in this project and would be the first one in line for the custom box. However, as a newbie, I am a puzzled by baffles. What exactly are they and what do they look like? Could you provide pictures of a good example of a baffle? Thanks.

Nihilistan

Def. of baffle: Front panel of a speaker enclosure on which the drivers are placed.

I just thought for those people who are interested in the whole custom sub concept might be interested in a baffle to mount to a box in the trunk.

Over the weekend I made some prototype baffles and a prototype subwoofer enclosure. I found some black plether that matches the interior almost exactly, so it looks almost factory. I have some pics, but have to have them developed and scanned (no digital cam). I'm unable to post pictures here... if someone is able to, please PM me and I'll send you the pics once I get them back.

I honestly don't have time to make custom boxes (assembly takes a while if you're going to do it right). However, I might consider making kits of pre-cut wood for assembly. Regardless, still need to work out some more details, the prototype is a box and sticks nearly 1' into the trunk. Next version will be better fitted to the "V" shape of the trunk opening and would only have to be a few inches deep.

-- Nihil

guji2

I can host the pictures on my website. I'll PM you my email address where you can email me the pics. Thanks.

spiroh

I need to see some pics. Sounds like an excellent idea.

guji2

Any updates on the install? When will we see pics? Thanks.

Nihilistan

Sorry guys... been busy working on the remainder of the project (crossover, wiring, etc...) haven't turned in the film to be developed. Guy from work is going to let me borrow his digital camera some time this week. Hopefully have pictures soon.

-- Nihil

xenon7

Infinitly baffle design as been around awhile. MTX marketed a sub that was called an "Elimiator" a light gray and pink sub that claimed no eclosure was needed to produce hard hitting 30- 60hz
in a car or truck. The idea works well when you follow the rule of isolating the front pressure wave from the back pressure wave the sub produces. I successfully made this happen in a pass-thru of a 1986 Old's Regal. I had to form a 7/8" HDFB panel and seal it within the rim of the pass-thru. The trunk is the box and resonates at its own frequency when shut.

Upside: no complecated box need, less material

Downside: Freq. control, higher power amp req'd for sub to move it. trunk size. sealing the trunk

I would consider this option anyway

guji2

Yo Nihil,

Got the pics yet?

Nihilistan

Man, when it rains it pours... A ton of sheot hit the fan since I started this post including having to attend an out of state funeral. So I finally got back and got a hold of a camera to take a quick pic. I sent the one that turned out best to Guji2 so they should be posted soon (thanks bro).

About the picture, if you look closely, you'll see that there is a small gap between the speaker and the upper left corner and that the box is not level (look at the right side of the speaker, it's somewhat covered by the seat).

This is not how it was designed, it's because I haven't completed the final install and 2 of us were in the trunk trying to hold the box into place while the 3rd snapped the pic. That lil bastard is heavy and hard to hold up cause it's so small.

When I do the final installation, there is a hook on the box that will be secured to a metal eyelet you can see hanging down at the very front center part of the trunk. The front baffle is actually larger than the opening to the trunk so the entire sub must be installed from the front after removing the rear seats and taking off the plastic trunk passthrough. The baffle is shaped like and replaces that plastic so the fit is damned tight... once you put the seat back on, it holds the front of the box in place so it cannot be removed from the trunk (you have to take the rear seat out).

I'll take some more pics when I do the final installation (hopefully this weekend after I finish the custom crossover).

-- Nihil

beerknurd

how does it sounds?

Nihilistan

I did initial testing in a sound room, but haven't gotten installed in the car (again, hopefully this week). Compared to a Velodyne 15" powered sub, when driven by a 375W amp it sounded awesome. It was tighter than the Velodyne and amazingly put out a lot of low bass. Did not hit quite as low, but I wouldn't expect it to. The SPL meter showed the -3 dB point at 29 Hz (1 meter on axis) but that was due in part to room response. SQ definitely better than the Velodyne.

-- Nihil

guji2

Hey Nihil,

Thanks for sending me the pics. I have hosted it on my website and here's the image:



The install looks AWESOME, even if it is not perfect. I definitely want this in my CL since I can't afford any loss of trunk space. Please send me more pics so that I can host them on my website. Thanks.

OKCL

That is bad ass. Are you just selling the baffle, or the box design itself? I would pay for the blue prints if you got them!!

Nicky Pass

That looks sweet!!!!! What does the inside of the trunk look like?

JakeCL

how does it sound when you put the armrest up?

guji2

I don't think you can put the armrest up in that configuration. Why would you want to put it up anyway? No one can sit in the hard middle without getting butt-ache.

JakeCL

maybe because it looks stupid down or so noone could see your speaker

Nihilistan

Right now I'm not selling anything... I barely had time to complete the prototype after taking all of the measurements, doing the calculations, testing the speaker, blah blah blah...

I'll give anyone who's interested the "blueprints". Maybe I'll get my website back up and post a full-fledged instruction if enough people are interested. On the other hand, if enough people are interested (say 5 or more), I would consider making them for sale.

I've also considered making a fiberglass mold of the trunk opening area to make a box that fits perfectly at the front of the trunk, but fiberglass boxes are less than perfect at best and require a lot of work. Need to have at least 10 people interested in this project before I'd even consider it.

Because this was a prototype, I made the easiest box to fabricate (a "cube"). If I remember correctly, the dimensions are 13" wide x 12" tall x 10" deep. I wanted to make it w/ a trapzoid that followed the cabin to trunk opening and would therefore make it take up less space (depthwise), but I don't have a table-saw and it probably wouldn't have fit together well. The front speaker mount (the front baffle) you actually see replaces the trunk passthrough and is nothing more than a couple pieces of wood that are attached to the regular enclosure. This is not a free-air sub mount. I suppose you could stack up a few of these mounts and mount the sub to any box sitting in the trunk.

The front baffle replaced the trunk pass-through panel... you can put the arm rest back up just like before so it covers up everything. Don't know how it will sound though, probably verrry muddy.

Maybe someone can go all-out and make something that automatically lowers the armrest.... if someone's good at fabrication and mechanics (and willing to rip up their seat), I can do the electronics.

This weekend when I do the final install (finished the crossover yesterday ) , I'll take pics of the inside of the trunk.

mc222

So...Any more pics?

Nihilistan

Had to do some mods to the crossover wiring... I should have it all reinstalled soon for some decent pics.

-- Nihil

mc222

Awesome! Looking forward to them!

Bluesman

I want to see more pictures and I am wondering how this addition would improve the stock Bose system. ( Bose - Knows no highs knows no lows).

mc222

Me too!!!

mc222

Any pics yet?

Bluesman

What ever happened to this?

mc222

??? Nihilistan said he would post after Thanksgiving...But Im still waiting....

Nihilistan

Guys, finally got some pics of the semi-final installation up for viewing:

http://photos.yahoo.com/denovj2002

Sorry they weren't sooner, but I just got back from a long business trip. Would have posted them sooner, but my server got disconnected (damn DSL) and I couldn't log in remotely. Anyway....


Regarding the sub. As you can see, it's a sealed box. The volume is approx .8 ft^3 if I remember correctly (it's the medium size recommended in the Kicker whitepaper). The front baffle replaces the rear trunk pass-through entirely (it must be removed). Because of this, the rear seat must be removed entirely to allow the sub to be installed (you cannot remove it from the trunk). The front baffle is sandwiched between the rear seat and the frame, so it is held tight to the rear seat. A loop screw mounted in the top of the box is bolted into the rear seat guide that drops down through the rear deck/frame... this holds the box into place vertically.

You can't see it clearly in the photos, but there is about 2" of space between the floor and the bottom of the box... I meant to leave enough room so the amp and crossover could be mounted underneath the sub, but I didn't take into account the angle the sub was mounted at (the rear of the seat is sloped).

You can close the rear armrest without any problem and it still sounds fine. However, I'd guess that the SPL goes down by about -3 dB. Doesn't hit quite as hard, but better than I would have expected. With bass-heavy material played loud, the sub will actually cause noises to come from the armrest as it tries to push/pull air from around the armrest.... it's hard to describe but it's kindof a leather "creaking" noise. Definitely not a grinding noise.

I have the crossover set to 24 dB/oct slope @ 70 Hz (both high-pass and low-pass). The high-pass outputs feed the stock amp and the low-pass ("constant bass" design) output goes to the sub's amp. During listening adjustment tests, I adjusted the crossover's low-end gain to about +3dB which seemed "flat". I'm extremely impressed with the sound quality and quantity of this little install.

Generally speaking, I think the sound quality of the sub is amazing. First off, there is more than enough bass. This thing can shake the mirror and your chest on any material. I'm only feeding it 200Wrms and would be scared to see what it could do w/ 400W. There's plenty of bass for my taste. What I really like about it is how accurate and tight the bass is... with a fun punch. I think there's something to be said about a driver firing directly into the cabin in a sealed enclosure. Definitely no evidence of group delay or phase smearing. Does not sound boomy or ackward as I've heard with sealed enclosures in the trunk.

Overall, the mids benefit a lot from being released from having to reproduce low bass. Male vocals sound 100% better, especially during bass-heavy material. There is the problem that bass always seems to come from the rear (it is) but I don't know a [reasonable] way around that. It's not too noticable unless you listen to certain types of music that have sweeping notes. Best thing I can say is because of the "constant bass"/non-fading low-pass crossover, I can move the fader to the front as much as I want... I'm just used to a soundstage in front of me as opposed to in the rear. Imaging is much better, again, due to the fader position and moving bass material to the sub. I'm considering changing the crossover design to a "Dolby Pro-Logic" - esque type and use the rears as surround sound. But for now, I'll leave em alone.

To give you an idea of how it sounds, I'll make a few notes based on some different types of music you might listen to/be familiar with.

Crystal Method : Vegas -
I didn't think this sub would hit the low frequency material on this CD. Surprizingly enough, it not only hits it, it hits it hard. I've listened to this on some insanely expensive equipment (like $100G+) and I can't say the bass is any better. There are a couple really low notes (not the sub-sonic stuff) the sub is probably about -6 dB down on (based on ear alone) but it's still there enough to feel. Thing that is absolutely best is how tight the bass is and the punch it has. Track 4 (i think) hits hard and goes on to shake your chest... absolutely fun.

Power106 FM : Misc R&B -
Big Boy and Teeto, keeping the morning/afternoon commute fun. They spin some pretty bass-heavy material. If you're looking to have people hear you for blocks, this isn't the right sub for you. If you roll up the windows, you can't really hear it's bumping. Nice thing though, the trunk doesn't rattle either cause the sub is firing directly into the cabin. If you roll down the windows, you definitely get a head or two turned to hear/see what's coming. Again, if you're looking to set off car alarms, this ain't gonna do it. Sub makes rap/R&B fun to listen to and you'll never go back to that stock sheot.

Stevie Ray Vaughan : Greatest Hits -
Little thing does a lot to help out bluesy type music with some beautiful basslines and textured fretwork... The crossover frequency might be set a little high for this type of music cause it covers such a dynamic range and there is definitely a spacial disconnect around the crossover frequencies. However, the front speakers sound much clearer due to not having to handle the deep bass. Obviously true of any system but I'd highly recommend anyone thinking of a sub putting a high-pass on the stock speakers. Certainly helps clarity a ton. The kick drum sounds true with a nice punchy feel... not too much color and it doesn't sound overly damped. Basically what you would expect with a sealed enclosure.

Pink Floyd : Misc
Simply put, if you listen to anything like this, you must get a sub. It's night and day difference. Listening to the wall before and after is unbelievable. The mids are so much cleaner and there's an overall dynamic that the stock system lacks. You get some serious chills during the hits. Again, tight kick drum and accurate basslines are key. The sound effect tracks are actually fun to listen to and don't lack the bass feel/punch of the stock system.

Again, sorry for the delay on these pics/details, but work has been insane due to close of the calendar year. Should be in town for the holidays if you have any more questions.

At the end of the day, I'd give this project a 8 of 10 rating. Only reason not a 10 is cause it took me like 2 months to finish and I didn't have the tools to make the box the shape/size I wanted (I originally wanted it to match the trapezoid shape of the trunk frame -- you can see the masking tape outline in the pics). I love driving around listening to different types of music... a must-have for anyone not happy with the stock system. Hell, even my in-laws commented on how it sounds (SCARY).

-- Nihil

mc222

That is beautiful man--Great job and THANKS for the PICS!

DRM600

what were you doing with the theta? it's not installed in the car is it?

Nihilistan

Again mc222, thanks bro and sorry about the holdup. things are just plain insane at work.

I used to work for Theta as a design engineering and still do a little consulting as needed. I used an old DAC chassis to hold the crossover I designed/built and it is bolted to the spare tire cover.
It's really nice having access to "prototype" parts and awesome tests equipment Their sound room is not too shabby for listening tests either.

I am really interested in building a discrete DAC for the car, but getting digital data from the HU back is going to take fiber optics to even start I suspect... does anyone know if any HUs/CD changers even offer digital out? Could hack into one but god knows how tight that would be considering they're so compact.

If people are interested in this subwoofer project, I'll offer again the possibility of a limited production run for cabinet kits. I think I can get an "in" at a local fab shop, but I haven't approached them on this due to the lack of interest. If we can get at least 5 people interested, I'd at least make the initial contact to discuss options. There's already one individual interested in taking even the prototype, which I might end up making by hand unless we get greater interest.

-- Nihil

guji2

Hey Nihil,

I was very much interested in this project but I couldn't wait for you to come back from whatever you were busy with. So I went ahead and got a stereo installed in my car with a custom false floor and everything. I will be posting pictures of this install next month.

By the way, your pictures look awesome. However, I was a bit disappointed by the trunk pictures. It appears that you installed a sealed box in the trunk. That took some trunk space which wasn't what I had in mind. I was thinking that the back of the subwoofer would be flush with the back of the trunk, thus preserving the trunk space 100%. I thought that you would be using the trunk as the "sealed" enclosure itself.

I guess I am a bit glad that we didn't go through with the install because I don't think I would have been satisfied with the sealed box in the trunk taking up space.

But nevertheless, I want to say that your creative install solution for the L7 subwoofer is quite amazing. I'm sure there will be much demand for this solution from people who aren't worried about the small loss of trunk space to the L7 box.

Thanks for keeping us updated on your install progress.

Nihilistan

guji2... glad things worked out for you bro. Guess it's a good thing didn't get too far down the road with your install if you would have been disappointed. Post pics of your install when you get a chance

I originally intended to have the box follow the trapezoid shape of the trunk. If it did, it only had to be like 4" deep. I consider that essentially nothing. If it turns out no-one's really interested in this, I'll never go to the next step and just stay with what I have.

-- Nihil

Nihilistan

Wanted to get some opinions on how this "template" might look. I wanted to make the original box a trapezoid shape to match the shape of the trunk opening but didn't have the time (or tools) for the first one.

Now that I know it's worth it, I'm looking to do it all over again and upgrading the entire system while I'm at it. I just "ordered" Rockford Fosgate amps (550x and 550s) for Xmas and b-day to replace the stock bose and my current sub amp respectively. Going to use the same kicker 8" square sub mounted in the pass-through.

I think I'm going to mount the amps and everything on the rear of the sub box. Because of the changed shape, the box will only be about 4" deep. Add another few inches for the amps and I'll only be losing about 6" of useable trunk space (at the very front). What do you think about this basic layout? Please forgive the crappy cut-n-paste... I don't have photochop installed ATM and wanted to do something quick. Thanks SilverKnight for the trunk shot

SilverKnight

hahahah ... I looked at the pic before reading your post. At first I was like darn, that trunk looks like mine ... then hey, it's mine

I want to go your route now since mine is too heavy and taking up too much space. The only thing stops me is the squeaking noice you have when the armrest is up. I got to find a way to deal with it.

OKCL

Keep going on this. I'm thinking about steeling your idea anyway. Well if you would be so kind to give me the dimensions of the box after you finish making it, steeling it would be much easier.

dnd2984

iTrader: (6)

wow tahts some good cut and paste. What all does your system consist of.

Nihilistan

KY Jelly Honestly SilverKnight, don't think this setup can compete w/ your system (it wasn't designed to). Although if space/weight is an issue I don't think much could beat it. The noise w/ the armrest up isn't that bad... I can't imagine it would be any different than someone w/ a big box in the trunk facing the passthrough.

OKCL: Which design do you want dimensions for? I can post the design for the prototype, but don't have the second one (trapezoid) figured out just yet. Been on a lot of b'ness trips lately and the system has taken a back burner. Suppose I could still take some measurements and post em here.

[edit]

dnd2984: All speakers are stock. I made the crossover and it's set for 24 dB/oct slope @ ~73 Hz (high-pass and low-pass). I mix all 4 channels (front/rear left/right) into the sub channel so it's a constant/non-fading bass xover. The sub's driven by a HiFonics Z200 amp (temporarily cause it was cheap).

I'd consider selling the whole setup at cost (sub, box, amp, xover, wire, distro blocks x2) if someone's interested. I have box and manuals for everything and it's basically like-new. Think that would be ~$400. If in the LA area, I'd even help w/ the install.

-- Nihil

OKCL

I am mainly interested in the trapoziodal design, but I'll take what ever you have. I really like it becasue of the pass through. Trunk space isn't that important to me, maybe to my wife however.