Low profile subwoofer discussion and build thread

[coloradojay]

I want more bass in my 01 Box S. I'd also like to eliminate some of the existing distortion from bass heavy music (likely either by raising the high pass crossover point of the door woofers, or being able to EQ bass out with a sub doing the heavy lifting). I'll likely do other stereo upgrades in the future, but adding sub-bass seems like the area it lacks the most from the factory, as well as the the trickiest to solve given the space constraints in the 986 platform. I've researched several of the shallow subs available on the market and last night I pulled the trigger on one of these:

PHS.13 - Phantom - Subwoofers - Products

They are available for about $100 shipped, which seems like a good deal given the specs and design. They claimed at the time of release that was is the shallowest sub on the market at 2" mounting depth. Even the 8 and 10" shallow subs I was considering are deeper than the PPI (2.5" for the Pioneer 8" and 3 1/4 for the JL 10"). Rated at 200 watts, it's not going to win any Bass competitions, but I'm hopeful it will be able to cleanly fill the bottom end at a reasonable volume.

I will likely build an easy to remove, tall wedge box (5" or so deep at the bottom up the seat back to maybe 2" at the top yielding just over 1/2 cubic foot) with the driver firing into the passenger seat. The idea being I can pull it out to reclaim leg room when when I want to.

This specs say it can operate in a sealed enclosure as small as .5 cubic feet and designed for only .75 cubic feet. I might play with some box modeling software to see how ports might work too (with the idea of porting under the seat to take advantage of some additional cabin gain), however it's not designed or recommended for ported enclosures likely because the throw is so shallow.

I'll post updates here as the build progresses.

Has anyone else installed a shallow sub in your Box? I've seen a bunch of the footwell boxes, but they mostly seem to have standard depth/throw small subs in them.

[SpikeJr]

I will be interested to hear how this works out for you. Many threads on subwoofer installs out there - from what I've seen, it's difficult to get one in place without compromising legroom, aesthetics, sound, etc...

I am finishing up an install and I think I'm going to be adding a sub at some point. Right now I have JL Audio C5-653's with crossovers installed. Also running a JL Audio XD600/6 amp located in the front trunk. The HU is going to be a Pioneer DEH-x6700bt which was a compromise after the Clarion CZ-702 sounded like garbage. That's another story...

Anyway - the 653's are a nice improvement over stock - however, the low end isn't quite where I would like it to be...an option might be to replace the 6.5" mid-bass in the door with a dedicated 6.5" woofer if I can find a decent shallow-mounting one.

If that doesn't produce the bass I'm looking for, I like the idea of the removable enclosure behind the passenger seat idea. I think you'll find that the space under the seat is going to be a challenge - running ports under the seat will limit the seat from being fully lowered. I believe that if you lower the seat as far as it will travel, that the structure literally skims the carpet when moving the seat forward / aft. There was some discussion awhile ago about using bushings and longer bolts to raise the seat - however, the unknown was the change in shear loading on those components in the event of an accident.

[JayG]

Ive also been looking for a decent sub for my Boxster. I often have my wife in the car, so a footwell or behind the seat enclosure wont work. I have the basic sound system, no rear or door speakers although I am about to add the rear speakers.

I want to go with a sub under the right seat. 2 in depth would work for the speaker without raising the seat rails, but I think 13" diameter may be too big. I was not planning to have an enclosure for it, just the speaker under the seat. I realise that is not the best way for bass, but ya got to work with what ya got.

There are a few powered subs that are smaller, but the only one I found that would fit without raising the seat is no longer made and I have not been able to find one on the web anywhere

When you get the sub, it would be interesting to see if it would fit under the seat with the magnet in the section that is lowered in the floor pan

[coloradojay]

SpikeJr,

That JL setup looks nice, but a 6.5 can only make so much low end without a substantial enclosure. My Boxster has the factory woofers in the doors, and they actually sound pretty good, but I'm thinking I'll just bandpass them up at like 120 Hz once I have a sub so they can sing in their more optimal range. I've read a bunch of other sub threads here and elsewhere including one that talked about a custom fiberglass enclosure behind the passenger seat, but there were never any pictures of that one. Some legroom will be lost, but my goal is to keep it to a few inches, so for short trips even I at 5'10" can tolerate it while letting my 5'6" wife pilot (however she usually isn't driving ;o)). It seems that any speaker-well design is going to get kicked with my size 12s. My idea for porting under the seat wouldn't be physical tubes under the seat, just that the port(s) would fire there. With an enclosure this small (~.5 cu ft) and cone this big, ports probably won't actually be a benefit over sealed. Any sub enclosure in the cockpit is tight, which is why I'm thinking removable would be ideal- no passenger=sub, passenger=no sub. I'm tempted to try fiberglass so it is more form-fit, but I don't have much experience with it, and it can be kind of a mess.

JayG,

There are some prefab under seat subs out there which might work if you can keep the passenger from lowering the seat onto them like SpikeJr mentioned- it's really shallow and narrow under there.

Running a woofer of any size without an enclosure would result in nearly 100% wave cancellation from the front to the rear. You could still probably feel it a little bit, you would probably only hear physical noise from the cone/surround travel if there is no baffling or box to cancel or line up the phase of the back of the speaker with the front. You'd almost definitely be better of with a bass shaker like: http://986forum.com/forums/diy-project-guides/28126-sound-system-upgrade-plus-subwoofer-answer.html

Still waiting for the sub to arrive...

[tonichristi]

Did you ever get your sub installed, G-money?
Pimpin ain't easy, playa.

[JayG]

Originally Posted by tonichristi

Did you ever get your sub installed, G-money?
Pimpin ain't easy, playa.

huh ?????

[Nine8Six]

Originally Posted by JayG

There are a few powered subs that are smaller, but the only one I found that would fit without raising the seat is no longer made and I have not been able to find one on the web anywhere

Jay I did stopped at the AV street last Sunday afternoon. Thousand and thousand of those mini subs. Well mini... all were something like 30*22*7cm. The smallest I saw was 6.6mm tall (2.25") but still very wide (6" SW). Loosing faith lol

I have a feeling your idea of using shims, spacer, on the seat bracket is the way to go x100. I wouldn't wait if I were you and just get it done your way.

ps. also notice from the available stocks here that the smallest it is i.e. width&length, the tallest it goes :/

[JayG]

Originally Posted by Nine8Six

Jay I did stopped at the AV street last Sunday afternoon. Thousand and thousand of those mini subs. Well mini... all were something like 30*22*7cm. The smallest I saw was 6.6mm tall (2.25") but still very wide (6" SW). Loosing faith lol

I have a feeling your idea of using shims, spacer, on the seat bracket is the way to go x100. I wouldn't wait if I were you and just get it done your way.

ps. also notice from the available stocks here that the smallest it is i.e. width&length, the tallest it goes :/

Thanks Fred.
If you cant find it, it probably does not exist

I'm gonna get some longer grade 8 bolts and some spacers and see if I can raise the seat 1/2 inch. I'm not overly worried about shear strength with Grade 8's and I tighten it down properly. Besides, if I'm in an accident where the shear strength of the bolts comes into question, I have bigger problems. In any case it would likely be my wife in the seat and she is well insured

[Nine8Six]

Originally Posted by JayG

Thanks Fred.
If you cant find it, it probably does not exist

I'm gonna get some longer grade 8 bolts and some spacers and see if I can raise the seat 1/2 inch. I'm not overly worried about shear strength with Grade 8's and I tighten it down properly. Besides, if I'm in an accident where the shear strength of the bolts comes into question, I have bigger problems. In any case it would likely be my wife in the seat and she is well insured

Gr8 in those size will do just fine is you get them in anything other than carbon steel (those get rusty quick).

Anything custom you need machined, just shoot me a quick PM. Just incl a basic hand drawing with dims. Got SS rods in 304 in all sizes here, can do any types of threads, length or sizes. Same goes for your spacers mate, anything fancy you need just let me know.

Thanks for helping me out on the RL forum btw

[JayG]

Originally Posted by Nine8Six

Gr8 in those size will do just fine is you get them in anything other than carbon steel (those get rusty quick).

Anything custom you need machined, just shoot me a quick PM. Just incl a basic hand drawing with dims. Got SS rods in 304 in all sizes here, can do any types of threads, length or sizes. Same goes for your spacers mate, anything fancy you need just let me know.

Thanks for helping me out on the RL forum btw

Thanks and my pleasure
The 996 Rl forum can be a bit brutal
more than a few wankers as well

[Timco]

Mine has the sub box that takes up the entire shelf over the engine compartment. Plenty of bass. 2x 8", pics if anyone wants to see it, but you lose the shelf. Great sound. It's the stock Bose unit that came with the SE.

[Giller]

Originally Posted by Timco

Mine has the sub box that takes up the entire shelf over the engine compartment. Plenty of bass. 2x 8", pics if anyone wants to see it, but you lose the shelf. Great sound. It's the stock Bose unit that came with the SE.

+1 I have the stock Bose surround like Timco and I think it sounds great.

[juiced99ws6]

Hey all,
I realize this is a fairly old thread but I have done a full custom stereo in my 2002 boxster so I will outline what is done.
I did the dual din conversion which was a pain in the butt, but worth it. Went with a Pioneer DVD player with 6.5 inch touchscreen. I did the micro-bypass so I did not have to hook it up to the e-brake and have full functionality at all times.
I then replaced all speakers with pioneer highs. I had the door and dash speakers in my car. When you do this the speaker buckets in the dash will have to be modified. There is a write up online for this that is very informative. The door speakers were direct replacements.
Now the door speakers will not do anything through the factory amp since the factory speakers were made to be purely for bass. With the updated deck you do not need the factory amp any longer. I removed the amp and cut both connectors off. Then I capped the amp power ground and remote wires. You should then be left with 8 wires out of each connector. You then find the corresponding colors from each bundle and simply splice them together. Also on the radio end you will have to cut the old harness to splice the wires on that end to the speaker wires on your new deck. You will have 5 wires instead of 8. One is a common negative for all speakers so you will just be splicing all four negatives to that wire. Then you simply match the colors for the other four.
Now since this whole thread was about bass, I used a Kicker Hideaway 8 inch woofer. I am 5'7 so I was able to put it behind my drivers seat and not lose any leg room at all. the seat back can still sit all the way back and the seat is only slid forward no more than about 2 inches on the rails. If you do not want to lose any personal legroom it could easily be installed behind the passenger seat back without your passenger even losing enough legroom to notice. It cost 300$, took about an hour to install, and provides substantial clean bass to my stereo. The car sounds amazing and everything can be heard crystal clear at highway speeds. Any questions feel free to ask.

[flete25]

can you post pics of the kicker hideaway sub install in your car ? I was thinking of buying that sub but wasn't sure were to put it since am 6'3" in guess ill put it behind the passenger side wife is only 5'3"...

[JAAY]

I am running a 987 footwell enclosure with an external amp. I have tried everything and this is the best solution and fits like factory. My .02

[JAAY]

http://986forum.com/forums/show-tell-gallery/37265-subwoofer-box.html

Since died black.

[flete25]

thanks jaaay !
very nice and it looks perfect fit..am gonna work on finding one for my car.

[Hogosha]

I know I'm a rookie to the forum, but I have been using the search button like crazy, trying to soak up as much information as possible. One of the projects I plan on doing this season is speaker upgrades, dash first, doors next, and eventual rear deck installation. I have not picked out a new head unit yet. The subject of Subwoofers has come quite a bit, and some of the solutions have been fantastic.

Like some, I would love an under the seat subwoofer, but the limited clearance has thrown a monkey wrench into our efforts. Nine8Six has even scoured the market place near him without any luck. But I think I may have found a limited solution, and if this has already been discussed, please disregard. It seems Panasonic makes, or has made the under seat Subwoofer in the Subaru Impreza. It measures 2" x 8.5" x 10" , and is 120W. Although not he most powerful, this form factor might be just the ticket for some of us here that just want a bit more OOMF to round out the sound. They can be had for as little as $80 used on eBay. I think it is a 6 wire plug that would need to be spliced.

[JayG]

Originally Posted by Hogosha

I know I'm a rookie to the forum, but I have been using the search button like crazy, trying to soak up as much information as possible. One of the projects I plan on doing this season is speaker upgrades, dash first, doors next, and eventual rear deck installation. I have not picked out a new head unit yet. The subject of Subwoofers has come quite a bit, and some of the solutions have been fantastic.

Like some, I would love an under the seat subwoofer, but the limited clearance has thrown a monkey wrench into our efforts. Nine8Six has even scoured the market place near him without any luck. But I think I may have found a limited solution, and if this has already been discussed, please disregard. It seems Panasonic makes, or has made the under seat Subwoofer in the Subaru Impreza. It measures 2" x 8.5" x 10" , and is 120W. Although not he most powerful, this form factor might be just the ticket for some of us here that just want a bit more OOMF to round out the sound. They can be had for as little as $80 used on eBay. I think it is a 6 wire plug that would need to be spliced.

that sounds perfect at least from the size.

do you by any chance have a part/model number?

[JayG]

found it on Ebay and found the wiring info on a Subaru forum
it gets power and both +&- signals from the rear speakers
the unit has gain and hi-pass adjustments

Looks like it should work fine

Good find!