Another attempt: Under the parcel tray

[WhiteR33]

Hello

I am planning to install a subwoofer underneath the parcel tray, next to the battery, in order to save maximum boot space. What size have people been successful with? Which way should the sub be facing? Angles?

I've seen fhrx's install of 10" in a small box, the other day. I realised that the HICAS Control Unit stayed in the same spot. Is there any reason that HCU can't be moved? That is, does it have some sort of g-sensor? I want to move is to the left or behind the battery, is that possible?

Cheers

Andy

[wolverine]

check PM

[cooks44]

I'm putting mine in there now, whole design leaves me with practically as much space as you have originally.

I'm putting a bandpass box in (all sound comes out port), with this port coming through one of the original parcel shelf speaker holes. Sub is an 10" Infinity Kappa Perfect. Factory recommendation is for a 0.6ft³ sealed box, or 0.95ft³ bandpass box which fits perfectly in this space! I don't believe the HCU has a sensor in it therefore it can be moved (well, it is in mine!) There is a sensor mounted under the edge of the parcel shelf (where my speakers now are) - this needs to be in the same orientation as it was installed.

I'm putting some plyboard up where the back cover (battery cover) would usually be, this will have my amp and stacker inset, whilst being on hinges so I can still get to the batteries behind.

It's a big job though, being done in about four steps. Up to step three now! Will have to post pics when it's finally finished!

[WhiteR33]

Wow! 0.95ft^3.... that's like 27L... How did you manage? Just wandering how much did that sub cost you, and where does your amp go?

Can't wait to see the pictures (before, during after work.... any)

Good Luck!!

[WhiteR33]

Also, just wandering, is your skyline a 2 door or 4 door r33?

[cooks44]

Yup, about 27L. This is Infinity's recommended enclosure size for a bandpass box with this sub. (Was going to provide a link, unfortunately their site is a little screwed.)

Two door R33 coupe, same as the majority. I had two goals: leave as much boot space as possible, and no noise/vibration in the boot. This was the only choice left! I was initially opting for an old Cerwin-Vega subwoofer I had around, but the box design was horrendous as it required around 1.8ft³ for its optimum box. I then saw the specs for this Kappa Perfect sub and its tiny box (sealed box is only 0.6ft³!) and figured it is the one.

They're fair subs, primarily designed for "quality not quantity" in their bass reproduction. These are their high-end subs, rated 1,400W Max or 350W RMS. Of course putting it in a sealed box (the back part of the bandpass box is literally just a sealed enclosure) causes it to lose half its dynamic level compared to a ported box, I prefer sealed for the control it gives the woofer, providing nice, clear bass notes.

For the amp I got a big 6 channel, I don't like the idea of having one power power supply on the circuit board for all those channels but don't really have much room to play with (Would really prefer two amps!). At least we all have very short cable runs from the battery! Might add a cap later just to be on the safe side. I'm replacing the carpet-covered, plastic panel that sits in front of the battery with plyboard on hinges, can then fold it down and get to the batteries still. The amp itself will be in a box-like structure, mounted to the back of this board. A cutout in the plywood lets the centre of the amp protrude through, whilst leaving the heatsink fins behind. These are force-fed air from the cabin, with the idea that on a hot day I let the 60°C air out of the cabin and might even turn on the A/C, but don't always open the boot. Stacker is to be mounted in this board too, majority behind with only the face in front for access. Running out of room for the stacker, so I'll see how I go once everything else is in.

Might have to scan my drawings for you to have a look at, I'm having enough trouble explaining what the design is to my chippy mate who's helping me build it without showing him! Give you a better idea. Check your PM for buying info on the sub.

Cooks44.

[WhiteR33]

I am a bit confused; are you running sealed or bandpass box? Does your amp can boost up to 300W all up?

I think the hardest part is finding a place to start, because I don't know about cars, nor do I know about car audio stuff, and I can't draw for crap.

If it's not too much trouble for you, could you please scan some drawings later? I kind of, designed a box, but I don't know if it will fit in that compartment because I don't have a proper measuring tool. The dimension at the moment is 14"(w)x14"(l)x 8"(h)....gives about 17L or 0.6ft^3. I think this sticks out by about 2 inches, but that was when I dreamt of putting in a 12". I will make a cardboard box to check soon.

Thanks for the details and expertise

/* Andy */

[cooks44]

Sorry, am sitting here at work rambling cos' it's too hot to work! Now, I'm not an expert - I've just done it a few times.

It's a bandpass box - I wanted all the sound in the cabin. Apart from having the box on the back seat (which is where it is now) doing this was the best way for me.

My amp is 6 channel, works out to about 71W RMS by 4, and 110W RMS by 2 (which when bridged works out to around 205-210W RMS for the sub.)

It's not easy at all to do this kind of installation without a fair woodworking knowledge. You end up building things that don't fit when you're working to such a small area. Happy to scan the drawings I've made - pretty crappy (may as well be drawn on a napkin) but gives you an idea.

Best way I found to measure is to get some wood offcuts, say around 14" x 4" off a plank. You can put one down on the floor and one against the back so you can see where things are uneven and where you have to allow for this. Then you can hold another plank under the parcel shelf to give you some much better points to measure from/to. Don't forget to allow for the width of the wood and the thickness of any carpet you're adding.

Perhaps it would help you if you started where I'm now at, changing the battery/electricals mounting and putting some wood in there...

I'm turning the battery around 90° and shifting it and the relay/fuse/whatever box as far left and back as I can. By taking out the original metal bracket and putting two MDF panels in there (you'll see there's an angle in halfway across where the floor starts bending down) you'll have much more room for your box and you'll have the main starting points for measuring and fixing to. Now, before I get flamed a few things:

- Don't forget your battery contains lots of acid! I'm planning on covering everything in heaps of lacquer, putting the battery in one of those battery boxes, and maybe making the base where the battery sits out of AC cement sheeting.

- Don't forget you car is primarily a car, and mechanics, etc will need to get in there at some stage. Your fuel pump, etc are all accessed through this area.

As I said, I'll scan these drawing to give you an idea of what I'm doing. Hope it helps!

Cooks44.

[WhiteR33]

Hey.... I was looking at some other forums, and saw that some people's rear speakers had holes put in by the subwoofer. What really happens there?

[R33TypeMS2Wooshka]

guys if by chance, ive got a coupe r33 and 2 twelves, can anyone give me the best place to put the 2 12" without restricting axs to the battery/hicas/pumps etc... and still have axs to the damn spare wheel if infact the police pull me over and say... no u cant and get defec ted...

cheers

PM would be most prefered as i barely am able to get on regularly enuff to answer back.... cheers

any drawings/dseigns/measurements that u can give me to help me in this endeavor... please do... cheers

:headspin:

or if any of u boys/gals are from around melbz area... specifically Dandy/noble/or north side near epping/reservoir and the like etc... i travel alot each day and if need be can come meet up with any of yaz to give me a better idea if theres need for it... cheers

[WhiteR33]

me just want to know if a sub under the parcel tray will pop the speakers? Any one???

cheers!

[cooks44]

It can... Have seen it happen. You need to be able to move a fair bit of air though! (ie. a single sub wouldn't do it).

R33 boots are pretty much fully-sealed, save for the vent strip along the edge of the rear window and a few holes behind the seats. If you're moving enough air that the vent can't keep up, the next weakest point would be the speakers themselves, the pressure pushing straight through the cone.

Either way, having any subwoofer pushing on your rear speaker cones will prevent them from producing a nice, clean sound.

As per PM, I'll send you my new drawings (sorry, I'm a slack ass.... No, I'm just a Uni student) and show you how I've moved my speakers outwards, so they're no longer protruding into the boot.

[jimmy 00]

me just want to know if a sub under the parcel tray will pop the speakers? Any one???

cheers!

the only way that would be possible is if the speakers above the sub are out of phase with the sub. (ie sub pushing outwards while speakers push inwards) this is done by the + and - being round the wrong way on the speaker leads or signal leads.