Under seat subwoofer/ stealth enclosure.

[rsbowling]

Hi,

I have a 2005 a3 sportback and am wanting to replace the boot sub with something a little punchier. I currently have the non bose system with a concert 2 headunit.
I have read the forums for a few weeks now and have come to a couple of suggestions that i would appreciate some advice on.
The first being a stealth enclosure. As far as i am aware andymac stealth only fits in the 3 door, is there a alternative to this arrangement? Also what is the favoured brand amongst keen audiophiles?
A alternative is a idea i have not been able to track down. I have been looking into underseat active subs, and was wondering if i remove the old sub, cut a piece of mdf to size so that it could use existing brackets, and then mount the underseat sub to that. Firstly would that fit in and perform well? Also would I be able to use the old audi amp to drive the rear speakers only? I have seen some clarion, vibe and alpine options on ebay.
I would add sound deadening material regardless of which modification.
My main criteria are to keep everything looking oem, but a bit more kick and quicker sharper bass from the sub, allowing me to drive the cabin speakers higher without distortion. I am very much a novice when it comes to car audio & vehicle electronics, however i realise obvious implications and sacrifices. For both options i have raised, are there any wiring adaptors for such situations? I really dont fancy chopping wires, ideally would like to be able to revert back to oem come the point of selling the car. Also does the existing sub have a feed to it from the battery? If so could i utilise this, or is it too under strength?
I have a budget of up to £300 and am not expecting top notch sound, just a improvement on the original, so it sound like it should do.
Thankyou in advance.
Richie

 

[AndyMac]

My stealth sub can fit the sport back but you have to modify the boot panel by pushing out the pointless scoop that would normally foul the speaker. Doubt you will find a small enough underwear sub to fit the space where the stock sub sits. Plus underseat subs are poor at best and designed to give your **** the impression of bass, rather than delivering proper bass, it would be even less effective mounted in the boot
You can still use the stock amp to drive the rears
No you can't use the stock power feed it is only 5 amp

 

[rsbowling]

Thankyou very much for your reply. I will rule out the underseat idea. How much is your stealth set up?

 

[Mart77]

What Andy says really, I can't remember any under seat sub that's real sounded good, done a few custom fits on BMW's in the stock locations under the seats that sound great however when it comes to real under seat subs go they suck I wouldn't waste your money.

brand wise my favs over the years it's deffo JL audio , dls , moral ........ Way too many to pick from, so it really depends on what you're looking for speaker wise if you're looking for sound quality I would probably say away from the main brands.

just out of interest what part of the country are you from? Reason I'm asking is I've been in the trade for a long time I could probably point in the right direction to hear sounding with your own ears

 

[rsbowling]

Hi Mart,
Thanks for the reply, i live in county durham. Just after a bit of punch and clarity. For the time being im doing a bit of soundproofing. Got some dynamat extreme and am going to to add that around speakers. Was thinking of putting some on the standard sub just to try firm things up. You any advice when soundproofing? Apart from this what would you recommend as a cost effective o, oem in appearence mod?
Many thanks
Richard

 

[Mart77]

You probably already know this but heat the dynamat up, in this weather using a heat gun is the best thing it just makes it a lot better to work with . Depending on how many sheets you've got I would go with the area around the speakers first then directly on the door behind where the magnet is, after that any large pieces of single layers of metal or weak spots on the door, also really push the dynamat into the door use a roller helps

Ok well if it was me I would go with a 2x 6" subs or a single 8" sub in a small custom side panel box and probably 30 or 400 watts rms will be plenty for what you're saying you want , you'll be surprised with the sound you'll get . One thing I will say is this kind of thing is down to the box get it wrong and you could make the best sub in the world sound like crap, get it right and you can make a poor sub sound great .

if you didn't want to take it to that level then you could try putting a after market amp onto the speakers and sub did it on a a4 cab once it sounded unreal

 

[Avantsline]

I recently upgraded the stock crap stereo in my Caddy van and went for an underseat Focal Ibus 20 active sub, plug and play straight into headunit for power but it is an iso connection so you may need an adapter if audi don't use an iso connection. on the vw caddy i had to get an adapter to connect an alpine hu iso connector to the stock stereo wiring feed then plugged the focal ibus into this when i bought it.

Very impressed with it to be honest punches a nice bit of bass, couldn't put anything in back of van due to work tools sliding about etc.

You can either screw it down or it comes with two velcro strips, works a treat. £200 dynamicsounds.co.uk

 

[rsbowling]

TThankyou both for your input. Mart, where would i put the aftermarket amp? Would a lower powered one work off the standard power supply? Also what are the main factors in building a stealth enclosure? Avantsline, that gives me something to think about! Have you done anything to your door speakers?
Thankyou
Richard

 

[Mart77]

Honestly it's totally std mate, reason being I've been around it since I was 17 and was in the trade for a long *** time at one point I was living car audio 24/7 if I was selling it or installing it we was building a spl car for competition. I'll never rule it out in the future .

common place is back of the back seats however false floor or under the front seats, if you've got the money to throw into in have a look at the the JL audio HD stuff it's pretty small or the new Rockford fosgate stuff they do a range that tiny smaller that the oem one.

box is down to the speak ts params which will be in the manual. Subs in that size only need small boxes if you're looking to DIY it probably going with a sealed box is a better option just make sure the box is sealed totally with no leaks. The recommend cuft of the subs will also be in the manual

 

[AndyMac]

If you remove the back right polystyrene bolster from under the boot liner you can mount the amp underneath for a stealth install

 

[rsbowling]

Thankyou for your replies, leaves a lot to think about. Today I decided to do a bit of soundproofing. I did behind the door speakers, and took the sub out and wrapped it in dynamat. Its has not transformed it I to b&o quality sound, however it has made a good difference. The sound seems to fill the car now, and I noticed I had to turn the volume down a couple and the bass also. a great 20quid spend.