Suggestions for A4 sub?

[DrNo]

Hi
Having tried unsuccessfully to get my factory rear speakers and sub to work with autoleads adapters, I've finally decided to replace the existing amp and sub. I would like an amp that powers a single sub and also the rear speakers but will let the new pioneer head unit power the fronts.

I want something that doesn't take much space so I guess my options are:
Replace the factory sub with a free air sub
or
Fit an enclosed sub in the boot cubby hole

I've seen sub boxes fitted into the rear left cubby hole (think AndyMac has done this with a 6.5" sub) but can't find any enclosures small enough to fit (and don't want to have to build one myself). If I could find a half decent sub-amp package that would fit that would be ideal.

Anyone able to suggest anything?
Also, just to check, in order to run a sub and rear speakers do I need a 3 or 4 channel amp?

 

[AndyMac]

You need a trimode amp or a 4ch with 2channels bridged for the sub, or use a mono amp (or 2ch bridged) and rewire the rears directly to the HU (which has been suggested about a thousand times on here)
There are no off the shelf solutions. You need to build your own, takes about an hour with a little DIY skill.
You also have to chop the back off the cubbyhole.

 

[dualmono21]

is this in the saloon or the avant
b5 b6 or b7

if it is the saloon there will be a free air infinite baffle solution if you wish
but as andy has allready suggested a home made box is the best solution
in either saloon or avant from

 

[DrNo]

Yes the rears are already wired up direct to the HU but I was wondering whether since I was getting a new amp anyway, I should get one with enough channels to wire the rears as well as the sub as they sound poo at the moment (or should I just get some new speakers)?
It is the saloon B6 version - there is already a sub mounted under the parcel shelf (perhaps 6.5" or 8") which I think would come out ok as their are screws underneath and the grill above is removable for access. I have seen a few free air subs for sale but a) don't know if they would fit b) don't know whether there would be much of a difference between one of these and one fitted in the boot in it's own enclosure. I might be wrong but as the sub mounting is steel and so should provide a nice solid foundation.
I have seen a couple of homemade enclosures on the web but seems like a lot of bother so was hoping I could buy one small enough to fit into the reccess in the rear right of the boot (which is roughly 12" X 12" at its widest point but tapers towards the back).

 

[dualmono21]

ive never put anything in a saloon version of the b6
ideally you would pick whichever side is biggest for the sub enclosure and work from there in the avant its the left hand side but the saloon may be differant
if theres allready a mounting for a sub and you would like to make use of this
if you can measure the sub and let us know what size it is i can advise on a suitable replacment which will be suitable for free air use
and also a suitable amplifier

will you be using brand new or secondhand equipment

 

[DrNo]

Yes the right hand side is the biggest - I'll take some pics this w/end and of the parcel shelf sub too. I've seen pics of other people home made enclosures in the available space but looks like soo much bother as I've never had a sub before let alone built the box (business opp for someone perhaps?).
Appreciate that-will find out the size of the sub also. Will be using new cheapish equipment - was thinking about a pioneer amp and sub as they do an 8" free air sub (if it fits) mainly due to the fact that I have a pioneer HU and it is the lack of it's compatibility with the OEM amp/speakers that I am having to buy new gear - so at least it should all work together. Sure I'm being overcautious but just want it to work!!

 

[DrNo]

Couldn't manage to upload any photos but the sub is 8" and is attached to a piece of sheet steel under the parcel shelf, facing into the boot (so the magnet bit is between the metal shelf and the parcel shelf above). Thought they were normally the other way around but I guess the infinite baffle idea wouldn't work anyway as there are quite a few holes in the steel mounting?
So would a replacement sub have to face the same way or would it be better facing into the cabin? And would I have to seal the holes in the mounting for it to work properly?

 

[dumdum]

Couldn't manage to upload any photos but the sub is 8" and is attached to a piece of sheet steel under the parcel shelf, facing into the boot (so the magnet bit is between the metal shelf and the parcel shelf above). Thought they were normally the other way around but I guess the infinite baffle idea wouldn't work anyway as there are quite a few holes in the steel mounting?
So would a replacement sub have to face the same way or would it be better facing into the cabin? And would I have to seal the holes in the mounting for it to work properly?

a sub can be mounted with magnet either way and still work just fine

for IB you would need to seriously reinforce the rear shelf and seal off any air gaps that exist, be they in the shelf/round the seats/over the wheel arch's, can be a complete ball ache to do properly and to do a half ***** job is pointless IMO and a waste of a sub, best way would be a stealth box on one side or the other

 

[DrNo]

I've decided to bite the bullet and build a sub enclosure. Should be able to fit in a 10" sub - the box will be sealed, about 20cm deep and total available volume will be about 17 litres (0.6 cubic ft). Can anyone suggest a good 10" sub and amp for less than £200 together. Thanks

 

[dualmono21]

you could probably do it very easilly secondhand but brand new you will not be getting good reliable equipment
if secondhand is ok let me know i have several options for good equipment
which will stand the test of time