Don't worry about it for now. I'm currently living out of a hotel, and all my tools are packed away in storage. I'm in the middle of purchasing a short-sale home, so it might be some time till I'm situated enough to actually do some creative work, so the project is on hold for the time being.

 

Now that the 'newish' JL audio 6wOs have found a new home, I do have a mono amplifier that was in my car prior to my installation of the 10". It is a Rockford Fosgate Punch 325.1 (325w @ 2ohm or 175w @4ohm) Has speaker terminals for two (2) subs, and this was installed when I was powering two (2) 8" subs at one time, and it had plenty of power. The amp has its cover, which makes a really good clean install (see pic when it was in the car - smaller one on the left) and it comes with a remote gain control and chord (about 20') that fits perfectly in that small sunglasses case near your left knee. I found the user manual too. I'd like to find this a new home also, asking $50 plus $10 to ship. Send me a PM if you'd like to have it, I guarantee it to work. Makes a good upgrade to the factory subwoofer output.

 

You had two 8 inch subs in your XK8? Where did you fit those...and "how" did you get them to fit......? How did you like those..?

 

I'd be interested but the up-side-down lettering indicates an obviously cheap knock-off amplifier. LOL - j/k

Beav

BTW, if anyone is interested in the subs I'll be happy to sell them for what I paid for them. I've decided to go in a different direction.

 

magnet, the two 8-inch subs were in a custom box, and we basically integrated it behind, and into the backseat seat cushion...we gutted the foam and wedged it in there, facing towards the boot. It wasn't the best location for subs, nor was it a concealed install, the box...though shallow, you could see the outline of it. I've got the box still though want it?

Beav, amplifier was sold to Bassmania, so which direction you headed now?

 

Probably MM691s in OE location. After looking under the rear seat and seeing how much space is already there, and never needing it for anything more than dead space, I may raise both the cushion and seatback a few inches...

I also think I've figured out a way to install a DD head unit - split the switch panel and move them to the sides or in place of the coin tray. I don't have heated seats (and would probably never use them anyway) so I don't have their oversized switches to deal with.

 

^ nice idea! that hazard button is pretty large though. I don't see enough room for it if the DD is centered...but if its say offset to the driver side (more room there) there should be plenty. Let me know if I can be of any help, sounds like a cool project.

 

Can always scour the boneyard for a smaller hazard switch and place its button on top of the Jag's button then mount it sideways (tall.) Don't really care about the ASC switch, it's more of a gimmick anyway. I've had an AVX800 in the Lincoln for about five years and enjoy it. Too bad JVC's subsequent models aren't 5.1 and/or sound as good. It would be nice if someone would make a Pandora compatible unit that didn't require using an iPhone. Or, at least, an android phone that would accept voice commands to change artists.

 

[QUOTE=h20boy;365701]magnet, the two 8-inch subs were in a custom box, and we basically integrated it behind, and into the backseat seat cushion...we gutted the foam and wedged it in there, facing towards the boot. It wasn't the best location for subs, nor was it a concealed install, the box...though shallow, you could see the outline of it. I've got the box still though want it?

Thanks for the offer. I've solved the sub problem...I was curious how you got two 8 inch subs in there..might take you up on that offer though.

 

You guys rock. And this forum is the best - really what the internet was supposed to be about. Am new member and relatively new owner of an 99 XK8. Love the car and can't believe I am driving such a great car. Car is fantastic but the back speakers were blown (who knew they were sub-woofers) and silence was the preferred sound over the ripped up bass noise from the rear. I got the build sheet from the dealer and found the car came with the premium sound. Agonized for weeks about what to do - then I found this thread. Gave me the confidence to fix it myself - followed the great advice from h2oboy and the experience of ek_mundo and mcoker. Bought the Kicker speakers for $130 bucks and they went in like butter. Took about 3 hours total - done very carefully. Instructions were letter perfect and the plastic trim cutting advice was very accurate - I cut back to the metal and the speakers fit right in - the freakin holes even lined up!! Sound is great and the enjoyment even better - thanks to everyone for sharing their experience. Rob

 

good work Rob, just remember, those little puppies don't like the rap music Hate for you to have to go back in and replace them again. lol

 

I just finished putting in my Kickers in the rear. Love to have great sound back after 6 months. Was impressed that the fronts could handle the music and really allowed me to wait for a while before tackling this job. Thanks again to all who submitted to this thread as it was fairly easy. One thing that I noticed though is I am missing a seat belt bolt cover! The parts search never ends!!!

Enjoy!

 

When making decisions on speakers with respect to impedance a couple things to keep in mind:

A lower impedance will draw more current at the same voltage (12V).
A lower impedance therefore gives more power at the same voltage (12v).
A lower impedance looks more like a short circuit (zero Ohms) and is more challenging for an amplifier to handle.
If an amplifier can handle the lower impedance they generally will deliver more power into a lower impedance speaker than a higher impedance speaker.
Some car amplifiers have internal power supplies that boost the power supply voltage for the amplifier to overcome the basic 12 volts we have to work with. A few of these will deliver the same power regardless of impedance but this is very rare.
Because of the relationship of power delivered for a given voltage, most car loudspeaker are 4-ohm where we worry about only starting with 12 volts. Most home loudspaekers are 8-Ohm where we have large voltage to work with.
Remmber, especially if you are lowering the imedance from the stck woofer either by dropping to a device with a lower impedance rating or if you parallel two woofers 9(cuts impedance in half) to check tha actual impedance curve. The impedance is not the same throughout the audio band, this is an average, the amplifier does not care about averages it cares about current draw. check the impedance curve (if available - usually you have to go on line) and look for the lowest point on the graph.

A good rule of thumb, don't install a loudspeaker or combination of prallel connected loudspeakers that will give you a low point below the lowest point on your stock speaker with a new speaker set up.

If you move up in impedance from 2 Ohm to 4 Ohm because you do not have data to figure out the above, you may have to turn the sub up a little more, depending on the efficiency of the loudspeaker itself but you should be relatively safe at the compromise of absolute volume.

If you move down in impedance it is likely to be louder but may draw too much current through output transistors and amp may fail early.

Best bet = match rating to amplifiers designed rating.

Good luck to all,
Steven Hood
Consultant in audio visual systems

 

Yah, what he said ^ I think I understand.

 

How is everyone wiring a new subwoofer amp into the system?

P.S. 4 ohms is safe; it puts half the load on an amp. I also went with the Kickers, great replacement. It was the only one I found that fit perfectly. Instead of machining down the plastic mount, I broke it off with a screwdriver. Ten minutes, done.

 

Regarding the ohm/impedance ratings on the sub woofers; going from 2 ohm to 4 ohm is not a big problem. Increasing impedance from 2 to 4 is OK. Decreasing impedance causes the amp to run hot and leads to premature failure. By substituting a 4 ohm for a 2 ohm you basically cut your amp power by about a third, but the amps runs fine. Might be a good idea to add the right resistor in the speaker wiring to get back to 2 ohms. It is common for auto manufacturers to use low impedance for subs as you get more power.

 

How do you remove the subwoofer grills? I need to replace the woofers and do NOT want to damage the interior.
Thanks for any help.
Will

 

they are actually easy to get out. The grills are held in by metal tabs attached to them, they tabs are bent outward once the grill is installed iinto the side panel slots for them. To get to them, simply take off your seatbelt guide, the top upholstered trim piece (convertible has three screws...ok, one of them is a snap. Once that is off, the interior panel just clips into place, or you could reach down and carefully pry those tabs out from the grill. eazee peazy

 

Before I found this fantastic thread, I spoke with Crutchfield technical support about speakers that would fit the XK8 subwoofer box. They did mention the Kicker 10CVT654, but also a JL Audio C5-650cw. This is a new JL and has a depth of 2 9/16", which I think is less than the Kicker.

I went with the Kickers anyway, though. They cost 1/3 as much as I was encouraged by all the sucessful installs on this bb. Amazon sold me the Kicker 10CVT654 for $49 apiece, whereas Crutchfield wanted $170 apiece for the JL Audio C5-650cw. Crutchfield did have some "scratch & dents" for $119 apiece.

 

I would like someone to try the JL Audios if they can afford it, I've tried 8-inch kicker and jl Audio's in a box, one installed after another, and I found the JL Audio always a bit better overall (output and quality). I think the JL Audio's are marine units, IIRC.