warbs

Hi,

Been looking at the stealth boxes http://www.autoacoustics.co.uk/sbo-si93.htm, they're pretty expensive, so I'm going to try and build my own sealed unit for a MY01, if it works I'll be happy to post dimensions etc. - would 12mm MDF be thick enough - I've got an entire sheet spare from building spacers for the fronts!

The entire system will probably be 4 channel amp - 2 channels for the front infinity 605's and one bridged for the boot.

Having never payed too much attention to bass boxes, should I go for 12" or a smaller woofer - I only want the bass for Dance and Hip-Hop ?

Cost and complexity are limitations. I want to be able to just connect the amp to the cars battery in the simplest way without messing around with capacitors and resistors and stuff. If this is going to limit my choice of amp then i'd be interested in comments...

Really stupid question - how do you control the volume from an amp in the boot, assuming it's taking an unamplified signal from head ?

Cheers

Chris

Si.t

I've thought much the same, and I prefer to make my own boxes rather than buy someone else's. I've heard the autoacoustics box uses 12mm mdf, however i've always used 15 or 18mm. Are you going to make the rear of the box with fibreglass? The best guidleines to follow are to ensure it is totally sealed, good quality build - I've put extra sound proofing inside to beef up the punch a bit.

As far as volume control goes, I assume you are talking about running an rca from the hu - you use the volume control as per normal as this controlls the volume of the internal amp and the signal srength on the unamplified output. As far as capacitors goes, you won't need one unless you run a very powerful 4 channel or two strong amps that draw a lot of amps - this is when you get the headlight dipping when the systems draws more power and saps it from the car electrics (lights being particularly current thirsty).

warbs

Thanks for the advice Si.

No I wasn't going to use fibreglass for the back of box - just MDF all round - I was intending to just shape the rear of the box to fit between the wheel arch and boot as snugly as is possible, and make the front nice and neat and squarish. All sized so it's still possible to lift out the spare wheel panel without moving anything.

Probably mount the amp directly on the back of the seat. What do you class as powerful?

Cheers

Chris

chiark

Go for a 12" in my opinion. I'm running 2 10s and thinking of changing to something a little bigger.

Regarding the build, 12mm is too thin. I always have used 18mm before now. However, the current box is built from 12mm reinforced with a lot of fibreglass to try to keep weight down - not sure I succeeded on that one

I prefer the sound of a sealed box, but ported may be the way to go if you want more output. Just be careful how you tune the port, as the driver loses suspension under the tuning frequency. This is an example of why the bass cube is so brilliant, as you can boost the snot out of the port frequency and have the subsonic filter track a third of an octave below to protect your woofer. Damn fine invention IMHO, especially for ported boxes.

nom

Err, chiark...
eh? Sounds nasty...

Moving swiftly on, what's the better direction for the speaker to fire in? Back into the boot, or into the back seats? I'd normally say into the boot, but I'm fitting the amp rack on the boot side (so everything is entirely hidden) & not sure if firing straight at the back of the amp is a good idea...

Sorry to semi-hijack the thread

chiark

I had the same question. The general concensus is "give the face of the subs the biggest volume to play into".

However, I did have some Infinity 120BRs that actively liked being played against the back seats. A bit of front loading helped em out nicely.

I think the answer is "suck it and see". But firing backwards works for me.