I have a 1997 XK8 convertible with premium sound system. The rear speakers (on either side of the car in the backseat area) contain a housing with one roughly 6” speaker and one roughly 1.5” speaker. The large speakers are wearing out and I’d like to replace them but am confused as to what type of speakers they are. Based on previous research, I was told they were subwoofers. They don’t however, produce any bass (only mid range sound). Oddly, the front speakers in the doors produce the bass. Why do these rear large speakers produce no bass when they are supposed to be subwoofers???

 

https://www.jaguarforums.com/forum/x...hlight=Speaker

This link has lots of info to sort through, plus several suggestions on replacements. Note the poster's name, search further under their name - you may find a detailed review of specific replacements.

Now, on your question: is it a sub or not? Well there clearly is a dedicated sub in the coupe, those lucky dogs can replace their fuel pump after removing the speaker.

From my experience listening and reading about it, I'm going to vote yes; your rear speakers are sub woofers based on the crossover circuit in the amp.
Now you and I know that its incredibly difficult to reproduce impressive, loud, flat low frequencies without a proper enclosure (sturdy materials [we're talking red oak for example, not pressboard or plastic], relatively large enclosure internal volume, ported vs sealed enclosure design = each are complicated to get right). You are further frustrated by the designer's choice of the high bass tone control crossover frequency & aggressive attenuation/boost steps built into the notched volume control. I'm going down this path for 2 reasons:

1) you can have more control. I, like many of us, added bluetooth to the system. My android phone, which now provides 90% of my music has much more refined graphic equalizer built in. The bluetooth feeds through the EQ to the amp.
2) I want to acknowledge that properly set up, you can get some very satisfying bass from this system.

Hope this helps, let us know how you do.
John

 

Thank you very much for the information. I actually figured it out. I had the stupid wires reversed. Someone who I think had the Alpine system said the black wire was positive, that’s the way I hooked it up. Then I read somewhere else that with the Harman Cardin system (mine), the black wire is negative. I replaced the OEM speakers with a set of Kicker subwoofers. Although Kicker told me they were a perfect fit, they were actually 1/16” too wide for the ring on the vehicles speaker box. I took a Dremel to the speakers and trimmed down the diameter and got them to fit.

 

Ah, the old out of phase effect! Glad you got it cleared.

John

 

Here’s what I did on an old post. Used Kickers too
https://www.jaguarforums.com/forum/x...-214035/page2/

Particularly liked Dale’s (crbass) input into the thread aka the speaker that can repel small moons

 

I'm getting ready to install some new speakers for the back of an 1998 XK8. An old post recommended Kicker 10CVT 654 shallow mount 6.5 sub-woofer, but those speakers have been discontinued. Can you post the exact speakers that you purchased? I was hoping that I can use 4ohm speakers as some posts have indicated that 1998 is 2ohns and not 4ohms. Original speakers are Alpine. I read where you can just repair the old speaker cones with new cones? I'm thinking that there have been a lot of changes to speaker quality and that it may be better to just buy new speakers. Thanks for posting.