XK8 Conv - Rear Subwoofer Replacement
#101
09-29-2014, 10:17 AM
As a new (bought just last week) and first-time owner of a '98 XK8 convertible, I am so glad I found this forum! Great resources. I've got a blown speaker in front and rear and want to replace them all. So as I've gathered, the stock audio system has a built-in crossover that sends only bass signal to the rear sub-woofers...ideally, I'd like to replace the stock with comparable subs instead of full-range speakers. I'm wondering if anyone has looked into using Kicker 40CWRT672? If they fit, these seem like they would be ideal since they are 2 ohms (like the stocks) and strictly subs (more punch!). Any thoughts?
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2005 XKR (04-04-2018)
#103
09-30-2014, 10:46 AM
I haven't pulled the old speaker out yet, so I'm not too sure...but I don't believe it is the upgraded system. Thanks for the tip on the enclosure. There doesn't seem to be a whole lot of choices out there for 6.5" or 6.75", 2-ohm subwoofers...perhaps I'll end up going with a decent 2-way.
#105
10-01-2014, 07:30 AM
Senior Member
As a new (bought just last week) and first-time owner of a '98 XK8 convertible, I am so glad I found this forum! Great resources. I've got a blown speaker in front and rear and want to replace them all. So as I've gathered, the stock audio system has a built-in crossover that sends only bass signal to the rear sub-woofers...ideally, I'd like to replace the stock with comparable subs instead of full-range speakers. I'm wondering if anyone has looked into using Kicker 40CWRT672? If they fit, these seem like they would be ideal since they are 2 ohms (like the stocks) and strictly subs (more punch!). Any thoughts?
#106
10-01-2014, 08:18 AM
Senior Member
Hi Andymax, welcome to the forum and congrats to your new toy. Rear speakers were my first task with my '99 Sapphire/ Oatmeal XK8 conv. ( notice guys, I stopped calling her Blue), I did replace my blown rear speakers with Kicker Compvt65 subwoofers. Install was easy enough. Speakers fit fine with a little speaker box trim. pleased with the results. Purchased on Ebay. Rich
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AndyMax (10-01-2014)
#107
10-01-2014, 09:04 AM
Thank you Rich, I am enjoying the new toy very much...just too bad I'll have to put it away for the winter pretty soon. But that's what happens when you buy a convertible in the Fall in the Midwest :-) And thanks also for the sub recommendation...found some on eBay for about half the price of the one I linked to on Crutchfield! Much appreciated!
#108
10-02-2014, 05:17 AM
The Kickers work fine. I replaced everything in my system. The head, amps, speakers and crossovers, but unfortunately, the sub enclosure is just too small to produce anything close to a thumpin sub system. It's WAY better than the original HK stock system, super clean/loud, but the super deep bass just isn't there. I'll have to take a pic of the rear speaker panels I made. The cloth ones are really bad as they don't allow much air pressure through them. I also put high end polk tweeters on the rear plates and replaced the pathetic HK tweeters in the front windows. I thought with the right crossovers and enough power to push the subs they'd produce more, but physics is against it. they make for really nice mid-bass speakers tho.
#109
10-02-2014, 09:14 AM
As a new (bought just last week) and first-time owner of a '98 XK8 convertible, I am so glad I found this forum! Great resources. I've got a blown speaker in front and rear and want to replace them all. So as I've gathered, the stock audio system has a built-in crossover that sends only bass signal to the rear sub-woofers...ideally, I'd like to replace the stock with comparable subs instead of full-range speakers. I'm wondering if anyone has looked into using Kicker 40CWRT672? If they fit, these seem like they would be ideal since they are 2 ohms (like the stocks) and strictly subs (more punch!). Any thoughts?
the speakers come with about 4 or 5 holes for screws. (u dont need the plastic top ring nor do u need to cut anything).
Even if they dont match up Perfectly to the jaguar holes u can at least get 3 good screws in there which is more than enough to hold the speaker in place securely. Thats what I did.
I didnt like the kickers at all. Ended up taking them out and replacing them with another brand. HOnestly as someoen noted this system and its stock amps and set up just isnt goign to give u a "WOW" sound. You can certainly get a good enough sound and better than stock, but unless u doign a complete overhaul it stops about there.
Good luck..its extremely easy if u follow the steps outlined in this thread. Everything comes off just as folks say. Took me no more than 20-30 minutes per speaker and that was putting everything back on as well.
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AndyMax (10-02-2014)
#110
10-02-2014, 12:44 PM
The Kickers work fine. I replaced everything in my system. The head, amps, speakers and crossovers, but unfortunately, the sub enclosure is just too small to produce anything close to a thumpin sub system. It's WAY better than the original HK stock system, super clean/loud, but the super deep bass just isn't there. I'll have to take a pic of the rear speaker panels I made. The cloth ones are really bad as they don't allow much air pressure through them. I also put high end polk tweeters on the rear plates and replaced the pathetic HK tweeters in the front windows. I thought with the right crossovers and enough power to push the subs they'd produce more, but physics is against it. they make for really nice mid-bass speakers tho.
#111
10-03-2014, 04:03 AM
Polk Audio DB1001 1-Inch Silk/Polymer Composite Dome Tweeters
Here's a link:
I used the existing tweeter housing (front), the fabric covered, triangle shaped plastic part on the jag, took out the old tweeter and mounted the Polk tweeter to the plastic housing. Used surface mounting parts from Polk. So the tweeter housing is essentially a "stand" for the polk tweeter. Looks cool. Sounds incredible. Also used surface mount for the rear tweeters. I made plates (covers) for the rear subs. (I'll have to take a pic) The stock rear tweeters, again junk, are barely heard. The rear polks really add nice surround presence. It's been awhile, but I think I used the rear tweeter leads or may have hooked them up to the "rear" balance of the new head amp. Sorry, can't remember. But the Polks sound great and give nice finishing touch.
Here's a link:
I used the existing tweeter housing (front), the fabric covered, triangle shaped plastic part on the jag, took out the old tweeter and mounted the Polk tweeter to the plastic housing. Used surface mounting parts from Polk. So the tweeter housing is essentially a "stand" for the polk tweeter. Looks cool. Sounds incredible. Also used surface mount for the rear tweeters. I made plates (covers) for the rear subs. (I'll have to take a pic) The stock rear tweeters, again junk, are barely heard. The rear polks really add nice surround presence. It's been awhile, but I think I used the rear tweeter leads or may have hooked them up to the "rear" balance of the new head amp. Sorry, can't remember. But the Polks sound great and give nice finishing touch.
#112
01-31-2015, 01:34 PM
Junior Member
Replacement Subwoofers for 97 XK8
I too had the rear subs disintegrate, and need replacement. After reading many posts, I purchased the Kicker 10 CVT65, 4-Ohm, CompVT Subwoofers as well. The install was no problem, however, the sound quality is terrible. At even a very reasonable volume, the subs pop, like they are not getting enough power. I double checked the wiring to make sure they were not out of phase, but have not been able to solve. I have to turn the Bass down on the Head Unit to -1 or -2 to keep them from popping. Has anyone else had similar problems/solutions?
#113
01-04-2016, 10:25 PM
nujagowner, did you get the system working? If you used the stock amp, it's really bad. No power and just plain dirty sound. Nothing about the stock system is good. I just got a newer jag and forgot how bad the original was so it's project time again. This time, I'll be doing something totally different for the subs in the back. Reconfigure the sub housing, add ports and tune it to 40 hz. I'll take photos of the entire job as I know this has been an ongoing issue. I'm still not happy with the kickers I put in the other jag. This time custom system. more to come...
#114
03-15-2017, 07:05 AM
XK8 Conv - Rear Subwoofer Replacement
I know this thread is a couple years old but I thought I would throw in my 2 cents anyways. I have a 97 XK8 coupe from my research the factory HK amp is 4 Ohm my front mids on the dash had a capacitor in line to filter out the low frequencies from what I seen on wiring diagrams and the pictures of the rear speaker housing the reason your factory speakers were rated at 2 Ohms was that they are wired in series with the tweeters which will combined be a 4 Ohm load
#115
08-22-2020, 11:31 PM
Junior Member
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I know this thread is a couple years old but I thought I would throw in my 2 cents anyways. I have a 97 XK8 coupe from my research the factory HK amp is 4 Ohm my front mids on the dash had a capacitor in line to filter out the low frequencies from what I seen on wiring diagrams and the pictures of the rear speaker housing the reason your factory speakers were rated at 2 Ohms was that they are wired in series with the tweeters which will combined be a 4 Ohm load
Did you ever find out what ohm speaker the real calls for? I've noticed that if you pan the real speakers from left to right, the bass stays in both speakers. Only the mids and muted highs pan. Would this validate your observation?
LMK,
JetBlackCat
#116
08-28-2020, 05:55 PM
Hi Badcat97,
A few thoughts :
1) anyone can mess with how car came from factory and there are differences between models so double check to see if this makes sense.
2) Professional audio consultant for around 40 years or so.
3) you probably have separate left, right and sub woofer amplifiers with sub woofer receiving a mix of lows from both left and right. Check this on control unit.
4) there are capacitors in series with mid/tweets to filter out lows and protect them from excursion damage. Although sometimes part of a crossover network, where you have the woofer receiving the lows, on my 03 XK8 with the HK set up these are just blocking capacitors.
5) You have some limits on power in cars, you start off with 12 volts. Power = voltage squared/impedance. So, until you go to a trick power supply, 12 v squared = 144 Volts, so 144V/8-Ohms = 18 watts. If you use a four ohm speaker 144 V/4-Ohms = 36 watts. if you use a dual voice coil 4-ohm, wired in parallel or a 2-ohm loudspeaker 144 V/2-Ohms = 72 watts. All these figures are increased with better units that have more power output but the relationship between impedance (ohms) and the voltage delivered is the same.
6) To get the max power transfer a lot of designers will use a dual coil (4-ohms each) sub woofer wired in parallel.
7) Some less expensive set ups will use a dual voice coil woofer with a passive crossover (capacitor) to separate the mid/high for left and right. The problem comes in here when you try to substitute speakers as the crossover matching of tweeter level to woofer level as well as the frequency it occurs at will change with a small change in the woofer impedance at that specific frequency.
8) If you have separate sub woofer control on your radio, don't worry about impedance matching to your tweets, woof is not connected to them. If you don't, use stock items or be prepared for some trial and error.
9) When connected in series (positive to negative, positive to negative) ADD the total impedance 2 Ohms + 4 Ohms = 6 Ohms, power is distributed proportional (twice as much power to the 2-Ohm speaker as 4-Ohm speaker).
10) When connecting in parallel and speakers are same impedance (4-Ohm and 4-Ohm) divide the initial impedance by the number of speakers 4 Ohms/2speakers = 2 Ohms. Power is distributed equally.
11) When connecting un-equal impedance loads in parallel, things are different, particularly if there is a large difference in impedance. A 4-Ohm speaker and 2-Ohm speaker in parallel will register around 1-1/2-Ohms with twice as much energy delivered to the 2-ohm unit.
Hope this background helps
A few thoughts :
1) anyone can mess with how car came from factory and there are differences between models so double check to see if this makes sense.
2) Professional audio consultant for around 40 years or so.
3) you probably have separate left, right and sub woofer amplifiers with sub woofer receiving a mix of lows from both left and right. Check this on control unit.
4) there are capacitors in series with mid/tweets to filter out lows and protect them from excursion damage. Although sometimes part of a crossover network, where you have the woofer receiving the lows, on my 03 XK8 with the HK set up these are just blocking capacitors.
5) You have some limits on power in cars, you start off with 12 volts. Power = voltage squared/impedance. So, until you go to a trick power supply, 12 v squared = 144 Volts, so 144V/8-Ohms = 18 watts. If you use a four ohm speaker 144 V/4-Ohms = 36 watts. if you use a dual voice coil 4-ohm, wired in parallel or a 2-ohm loudspeaker 144 V/2-Ohms = 72 watts. All these figures are increased with better units that have more power output but the relationship between impedance (ohms) and the voltage delivered is the same.
6) To get the max power transfer a lot of designers will use a dual coil (4-ohms each) sub woofer wired in parallel.
7) Some less expensive set ups will use a dual voice coil woofer with a passive crossover (capacitor) to separate the mid/high for left and right. The problem comes in here when you try to substitute speakers as the crossover matching of tweeter level to woofer level as well as the frequency it occurs at will change with a small change in the woofer impedance at that specific frequency.
8) If you have separate sub woofer control on your radio, don't worry about impedance matching to your tweets, woof is not connected to them. If you don't, use stock items or be prepared for some trial and error.
9) When connected in series (positive to negative, positive to negative) ADD the total impedance 2 Ohms + 4 Ohms = 6 Ohms, power is distributed proportional (twice as much power to the 2-Ohm speaker as 4-Ohm speaker).
10) When connecting in parallel and speakers are same impedance (4-Ohm and 4-Ohm) divide the initial impedance by the number of speakers 4 Ohms/2speakers = 2 Ohms. Power is distributed equally.
11) When connecting un-equal impedance loads in parallel, things are different, particularly if there is a large difference in impedance. A 4-Ohm speaker and 2-Ohm speaker in parallel will register around 1-1/2-Ohms with twice as much energy delivered to the 2-ohm unit.
Hope this background helps
#117
09-06-2021, 04:28 PM
After some searching I found a subwoofer to replace the blown rear units without breaking the bank or the need for major surgery to get them to fit. The replacement speakers are the Kicker 10 CVT65, 4-Ohm, CompVT Subwoofer. Nice sound.
The mounting holes match and the required depth is less tham the original equipment. Retail they would have been $100 a piece. On the Internet, I found them for $66 each.
Another alternative, the JL Audio 6w3v3 would have been about $120 over the net and may have needed modification to interior of the subwoofer boxes to accomodate their mounting depth.
Installation on the Kickers only required removal of the speaker grills and then trimming of the plastic rim that surrounded the original speakers. Dremel makes a neat attachment to cut or form things like plastic (cost $16.00). The removal, modification and installation took maybe 40 minutes or so. FYI, the solid black wire is the positive & black with white stripe is negative.
Not the audio system sounds better than the day I drove her home the first time.
Later
Ed K
The mounting holes match and the required depth is less tham the original equipment. Retail they would have been $100 a piece. On the Internet, I found them for $66 each.
Another alternative, the JL Audio 6w3v3 would have been about $120 over the net and may have needed modification to interior of the subwoofer boxes to accomodate their mounting depth.
Installation on the Kickers only required removal of the speaker grills and then trimming of the plastic rim that surrounded the original speakers. Dremel makes a neat attachment to cut or form things like plastic (cost $16.00). The removal, modification and installation took maybe 40 minutes or so. FYI, the solid black wire is the positive & black with white stripe is negative.
Not the audio system sounds better than the day I drove her home the first time.
Later
Ed K
4 ohm mine say 2 ohm. That's not a problem or were yours 4 ohm to start with? How do you get the full panel off each side? Remove rear seats?
#118
09-06-2021, 04:29 PM
After some searching I found a subwoofer to replace the blown rear units without breaking the bank or the need for major surgery to get them to fit. The replacement speakers are the Kicker 10 CVT65, 4-Ohm, CompVT Subwoofer. Nice sound.
The mounting holes match and the required depth is less tham the original equipment. Retail they would have been $100 a piece. On the Internet, I found them for $66 each.
Another alternative, the JL Audio 6w3v3 would have been about $120 over the net and may have needed modification to interior of the subwoofer boxes to accomodate their mounting depth.
Installation on the Kickers only required removal of the speaker grills and then trimming of the plastic rim that surrounded the original speakers. Dremel makes a neat attachment to cut or form things like plastic (cost $16.00). The removal, modification and installation took maybe 40 minutes or so. FYI, the solid black wire is the positive & black with white stripe is negative.
Not the audio system sounds better than the day I drove her home the first time.
Later
Ed K
The mounting holes match and the required depth is less tham the original equipment. Retail they would have been $100 a piece. On the Internet, I found them for $66 each.
Another alternative, the JL Audio 6w3v3 would have been about $120 over the net and may have needed modification to interior of the subwoofer boxes to accomodate their mounting depth.
Installation on the Kickers only required removal of the speaker grills and then trimming of the plastic rim that surrounded the original speakers. Dremel makes a neat attachment to cut or form things like plastic (cost $16.00). The removal, modification and installation took maybe 40 minutes or so. FYI, the solid black wire is the positive & black with white stripe is negative.
Not the audio system sounds better than the day I drove her home the first time.
Later
Ed K
4 ohm mine say 2 ohm. That's not a problem or were yours 4 ohm to start with? How do you get the full panel off each side? Remove rear seats?
#120
09-08-2021, 06:25 PM
After some searching I found a subwoofer to replace the blown rear units without breaking the bank or the need for major surgery to get them to fit. The replacement speakers are the Kicker 10 CVT65, 4-Ohm, CompVT Subwoofer. Nice sound.
The mounting holes match and the required depth is less tham the original equipment. Retail they would have been $100 a piece. On the Internet, I found them for $66 each.
Another alternative, the JL Audio 6w3v3 would have been about $120 over the net and may have needed modification to interior of the subwoofer boxes to accomodate their mounting depth.
Installation on the Kickers only required removal of the speaker grills and then trimming of the plastic rim that surrounded the original speakers. Dremel makes a neat attachment to cut or form things like plastic (cost $16.00). The removal, modification and installation took maybe 40 minutes or so. FYI, the solid black wire is the positive & black with white stripe is negative.
Not the audio system sounds better than the day I drove her home the first time.
Later
Ed K
The mounting holes match and the required depth is less tham the original equipment. Retail they would have been $100 a piece. On the Internet, I found them for $66 each.
Another alternative, the JL Audio 6w3v3 would have been about $120 over the net and may have needed modification to interior of the subwoofer boxes to accomodate their mounting depth.
Installation on the Kickers only required removal of the speaker grills and then trimming of the plastic rim that surrounded the original speakers. Dremel makes a neat attachment to cut or form things like plastic (cost $16.00). The removal, modification and installation took maybe 40 minutes or so. FYI, the solid black wire is the positive & black with white stripe is negative.
Not the audio system sounds better than the day I drove her home the first time.
Later
Ed K
How did you determine the rears were no good? I'm asking because mine only had terrible, muddy non musical sounds coming from both. I took them both out and they looked new. I hooked them to my home stereo and they played fine.
I hooked them back to the car, same muddy non musical noise. Is it fair to assume it's the amplifier rear channel? Should go ahead and replace the amp? Is there another test?
thank you
Mark