ALi-B

iTrader: (1)

This maybe helpful to anyone who doesn't want a sub in their boot....

Sure nothing is going to beat a big enclosure (With subs bigger is always better ) not even with quarter-wave folded horn enclosures. I know from my experience with OEM underseat/footwell setups; Honda, Mercedes, and BMW they do give the bass that the door speakers cannot replicate, albeit a little boomy or "plasticy" sounding resonance (well, they often are plastic enclosures).

But if you "have to have one" we need some closure....

So here I am....in the shape of upgrading the audio my old Jag....Whilst I'm on the verge of binning the Focal front speakers as they are so disappointing, I convinced myself to sort out the bass first; The 6x9" aren't upto the job as the rear quarters vent outside they are running pretty much in free air meaning the cone's suspension struggles to cope with controlling low frequencies. Now I assume nobody is familiar with the chassis/bodyshell construction of a XJ-S, so I'll explain it...the boot is a totally sealed area...unlike modern saloons and coupes which vent cabin air through the boot, the XJ-S has no air path between the boot and cabin; The cabin is vented out behind the rear windows instead. Behind the rear seats is a sealed steel bulkhead, behind that is soundproofing, behind that is the spare tyre, battery and fuel swirl pot; That's probably about 2ft of separation area between the boot and cabin. The rear C-pillars and rear quarters are sealed and wiring through the cabin is via grommets. Its made like this to stop battery and fuel fumes entering the cabin (batteries and fuel tanks were open vented back then), its also possibly done for Federal (American) crash safety to stop a fuel fire spreading into the cabin, as this was the late 1970's and the Ford Pinto was fresh in the minds of American vehicle safety boffins/politicians. British Leyland was probably petrified of being sued should it ever sell a car in the USA that could kill someone from a fuel fire (the Americans don't like foreign manufacturers....just look at the flack VW and Toyota have got recently).

Anyway enough of the history: Unlike a scoob which vents the cabin through the boot, a sub in the boot of a XJ-S is fairly pointless as all it'll do is shake the car and you'd probably need a pair of 12" subs in a huge enclosure with huge amps to be able to get some decent bass heard in the cabin. Trust me, I tried it with the 12" MTX sub and amp out my Golf and whilst it rattled the car nicely, it was more audible outside of the car than it was inside and was useless at lower volumes.

Underseat sub is the most practical option. So I bought one...a Kicker hideaway 11HS8

This was not done ***** nilly...I looked long and hard at Focal's iBus20 and Pioneer's TS-WH500A. The Kicker is the most expensive, I've had Kicker subs before and I currently have a pair of old 8" substation in the boot of my Golf as I wanted more boot space as the previous MTX guzzled most of it.

Well its all plumbed in, as you can see from the pics its a very tight fit!

Verdict...suprising. It is by far more powerful and gives tighter bass than any OEM underseat/footwell setup I have come across so far. It does go low, it does rattle the interior and it kicks, everything you expect it to do really. The only criticism sound-wise is its a little boomy on the higher bass notes and its doesn't go quite as loud as some may want it without the bass starting to go flabby. Obviously the frequency response doesn't go as low as a traditional sub, but its low enough for me and certainly dishes out the bass which none of the the other speakers can muster (the front were already on a 100hz HPF as they just sound nasty when allowed to produce anything lower - cardboard door cards can be blamed for that).

The build quality of this sub is IMO pretty good, its solid and heavy, the speaker cone is a aluminium disc, the enclosure is very solid feeling metal. The only thing I could comment on is maybe better quality stuffing could improve its response (or maybe not).

The installation kit is OK, including a nice long battery lead. Although the wire is aluminum, not copper and the blue remote turn-on wire is way too short; It didn't even reach halfway, which as you can see from the pics the sub isn't that far from the head unit.

Only other criticism is no proper low level input (phono sockets), you have to fit some phono plugs on the high-level input wires. I just used the speaker outputs from my headunit as it has no sub pre-out, but its a bit of an **** if you wanted to use sub-pre-outs.

All in all a thumbs up. Next job is to sort out those damn Focals.

For the record the setup is as follows:

Pioneer DEH-P6100 head with CD-RB20 aux adapter
Focal Access 100AC 4" 2way coaxials (disappointing for the price) Front
Pioneer TS-6987 4-way 6x9" Rear
Pioneer GM-X564 4ch amp (powering both front+rear)
Kicker 11HS8 Sub

Some mixed pics of the sub (including autopsy) and speaker install: