Bass box in audi 90?

[CHEN]

Calling all sound geeks. I have just got hold of a 10" audiophile sub speaker and a kenwood KAC-529S amp at a very reasonable price (free), Couple of questions are either any good? is it worth building a bassbox in my boot bearing in mind they are sealed in by a fuel tank? and a metal parcel shelf?

[iain1067]

Dunno but if it's a quattro you won't have much boot space left. I have always thought saloon cars stereo systems sound better anyway cos the boot naturally acts as a speaker box, i got some really nice 6.5 inch speakers into the rear shelf of my old 90 by cutting a little of the metal away underneath, i was delighted with the results, depends on what kinda sounds you want.


iain


iain

[s2carlo]

BTDT.
My previous car was a 90 quattro.
First I put an amp with bassbox in the trunk but the sound was to much muffled. (open boot sounded fine, close the lit and nothing was left)

I didn't want to cut such a big hole in the steel plate to preserve stability in the rear. (seen some dramatic things).

I ended up with two big oval speakers on top of the shelve.
This was changed with an MDF panel to get is flat and enough space for the speakers to go into without cutting big holes in the shelve and the steel plate below.

This setup worked fine..

Good luck
Carlo

[CHEN]

Thanks guys I think I will lose the bassbox idea and just get some good speakers for my shelf as and when I can afford it

[Fat Audi 80]

I had a bass box in my Audi 80 saloon. IMO it sounded great. You will always get a better bass response from a dedicated sub rather than some full range speakers on the rear shelf.

The most important thing IMO is to have a correctly designed box (either ported or non ported.) My box in the '80 sport was ported and I think that helped in the sealed boot...

Cheers,

Steve.

[Rusty]

Ported 10" sub, somewhere between 30 and 35Hz is the way forward BTDT.

The boot sealing is nowhere near good enough and will damage the speaker, unless it's designed for free air operation.

Making a box is quite simple, 18mm MDF and lots of screws. Seal all joints with silicon sealer or no-more-nails type stuff and give the inside a couple of coats of varnish as MDF does breathe. A couple of layers of loft insulation on the bnack face should help dampen internal reflections of the box too.

Or just buy one from Halfrauds, not a bad price at £40 with carpet etc. TBH.

Programs like boxplot can be used to calculate response curves, or do some research and find out what the manufacturer recommends in terms of volume and port diameter & length.

I've designed a couple of boxes for my cars over the years and they've used a pair of 10" subs with some stinger ports. Always been quite happy with them, although a pair of 12s has alwas been very tempting, shame I can't fit them in the boot of the S2!