I've been investigating the audio system in the X150's...

...because i'm not really thrilled with the sound quality. It's been mentioned before that there is a definite lack of midrange in these cars, which is no surprise since there aren't actually any midrange speakers, well not like the other JLR vehicles; for example the XF and the F-Type have 100mm midrange speakers in the doors, the Freelander2 has 80mm midrange speakers in the dash, the X350 XJ has 60mm midrange speakers in the dash, etc, etc...

The X150 has a really ****-poor audio system in it, especially when compared to the other JLR vehicles that had been in development at the same time, or even released a couple of years before (e.g. the Discovery 3, the Freelander 2, etc)

Anyhow, here's a breakdown of the good and bad.

There are three different audio systems available in the XK.

The Base system, "4x 25W", 6-speakers on 4 channels.
No subwoofer, no centre speaker, the front doors have a bass and a tweeter, which are on the same channel.
Really crap speakers, exact same ones as the Base audio in the X-Type!

The Alpine system, "525W", 5 channels plus sub, 8 speakers on 6 channels.
Subwoofer in the passenger footwell, centre speaker, bass & tweeter in the doors, again on the same channel.
Better speakers, all Alpine branded except the sub. Same tweeters as the Alpine system in the X-Type and X350 XJ, but the others are unique to the XK.

The Bowers & Wilkins system, basically the same as the Alpine except the speakers were changed to the B&W design, which is yellow kevlar cones, and the tweeters have aluminium domes. Same 525W rating. Same amp, same head unit, same subwoofer, so far as I can tell, same software too. The 525W rating is total BS by the way.

When comparing the Alpine/B&W XF/LR2 system in the XK, to the B&W system in the XF, and the Alpine system in the LR2 (those two are all but idential, btw) aside from the massive difference in speaker count; 8x vs. 15x, the other difference is the channel assignments, the XF/LR2 has 10 channels, the XK has 6 channels. What's crazy here is that the audio head unit in the XF, XK and LR2 is the exact same unit, same part numbers even. The difference is the amp in the XK...

In the XF/LR2 the front stage actually has separate channels for the bass speaker in each front door, and the tweeters & midranges on each side as well. This means the bass speaker has just to produce low tones, the tweeter and mids take care of the midrange up.

In the XK, the bass speakers in the doors get the whole sound spectrum (less the lowest tones that the sub handles), and the tweeters, wired in paralell, reproduce only the higher frequencies, thanks to a capacitor which is functioning as a high-pass filter (budget crossover). This is actually even worse than the Alpine system in the X-Type, which has a separate channel for each front tweeter...

So regarding the speakers themselves...

Tweeters;

Here's one of the B&W tweeters, and the Alpine tweeters, as you can see they were made in the same factory, the difference is that the B&W one has the aluminium dome, the alpine one has a silk dome.





The capacitors are different, but I don't think that makes much difference here, given that both are used in the exact same application.

Unfortunately I threw out the "base" tweeters from my old X-Type, which were the same ones used in the base system of the XK. They were branded Philips, and looked much cheaper than the Alpine ones...

Door bass speakers;

They are 165mm or 6.5", here's a comparison of the B&W bass speaker from the XK, and a B&W bass speaker from an XF. The construction of the cone is basically the same, except for the raised dome in the middle of the XK one, and the hole in the middle of the magnet. The hole is venting the raised dome. I can only assume this is to try and get a bit more midrange & treble out of it, given that it get's the full frequency range, whereas the XF one is only for low frequencies.





And here is a base bass speaker from an X-Type and the XF B&W, you can see the base ones are pretty crap in comparison, don't even need to hear them to know it...




I was going to try fitting one of the XF B&W bass speakers in the XK, they will bolt in if we trim off the locating pins, the three bolt holes line up perfectly, and I can make an adaptor cable, have the required connectors here so there's no need to cut the wiring, but with the full range going into these bass speakers, I can't imagine there would be much improvement. And the construction, design and weight of the XK and XF ones are so similar anyhow. The weight is important!



Centre Speaker;

Here's the Alpine branded centre speaker, it's 100mm or 4", alongside it some midrange and surround speakers from the later Meridian-equipped cars. What's most obvious is that the XK centre speaker also takes the full frequency range, it has no capacitor, and the magnet is friggen huge. Sadly it's a single-cone speaker so it doesn't reproduce the highs like the later coaxial ones do...




The B&W is the same design, just with yellow Kevlar cone



This speaker has to do the job of both the surround sound, and the midrange in the front stage, to be honest it's such a compromise, it doesn't do either job particularly well. I was hoping to put one of the "B&W" coaxials from the X351 XJ and the 2012 XF in here, but i'm afraid they won't handle the lower frequencies like this one does. Not only that the mounting holes of the later model speakers don't line up so it wouldn't just bolt straight in anyhow.

Subwoofer;

This was the biggest disappointment...

The sub is a 165mm or 6.5" driver, mounted in a ported enclosure in the passenger footwell. The amp is mounted to the enclosure. This driver is the cheapest, nastiest piece of crap i've ever seen in a late model JLR vehicle...





Shocking... To make matters worse the internal cavity of the enclosure is so tight, it will be tough to find an aftermarket sub to fit. Might need one of those reverse cone type drivers.... not sure which way to go here, but there is room for improvement no matter which way we go...



So that's the factory systems. What can we do to improve it?

Well the biggest limitations, in my opinion are;

- The front doors only having one channel each, and full range going to the bass speaker in the doors.
- The lack of midrange speakers in the front stage.
- The awful sound quality of the rear bass speakers, probably because of no tweeters or midrange.
- The sub is a bit weak.

Compared to the the XF and LR2 (and even my XJR) the lack of midrange in the front stage is terrible.

I set the DSP to the front, and the Surround turned down a little so that you can't hear the garbage coming out of the rear speakers. .

I've got the Bass and the Sub set to full to get the best out of it, that shouldn't be but that's how it is...

So what's the solution?

Well without adding more channels to the amp, and midrange speakers to the front, it's always going to suck...

But first of all, adding some tweeters to the rear is worth a shot. The problem is that the two potential locations to put tweeters, will basically blast a rear passenger right in the ear. So anyone unlucky enough to ride in the back will not only need their legs amputated, they had best be deaf as well...

Two potential locations I can see (the cardboard cutouts)




This may or may not be worth the bother. And cutting holes in the trim panels is something I'd have to be 100% sure about before jumping in. I'd also insist on using the OEM tweeters, along with the grilles and mounting taken from the front doors, so they match. I'm on the fence about this to be honest. But this would not need any extra channels on the amp, since they would be wired up same as the front doors are now.

What we really need is the same front door split channels like the other cars...

Maybe it will be possible to run an amp from a B&W XF or Alpine Surround LR2, since the head unit in the XK is the exact same one as the XF and LR2, this would give us two channels to each front door, while still having the centre dash speaker channel. I will need to get another amp and test this out. Without this I think it will be difficult to improve the sound much, even if I can get some midrange speakers in the front.

The alternative to this would be to ditch the factory amp altogether, and use an aftermarket amp. But this would need some sort of interface to take the MOST fibre optic signal, and convert it to multiple analogue channels. At the moment i'm not aware of such a device, but potentially there could be one, from an Aussie company called Mobridge. They have their DA3 DSP Proffessional interface, which works with later model JLR vehicles, it "may" work with the system in the XF, XK and LR2, perhaps some different software would be needed for it. It won't be cheap to get this working though...

Now, IF the XF/LR2 amp works in the XK, and we get the extra channels, then adding a midrange speaker to each front door would be an option, but, the problem is where to put the speaker. In the XK the seat controls are exactly where the midrange speaker would have been in the XF. And there's no space in the corners of the dashboard to put the midrange speakers like we have in the LR2 and in the X350 XJ...

This is the only spot they will fit without looking like a hackjob;



They can't go any higher, because of the end of the dashboard meeting the door.

I honestly don't know if this position will be high enough for the sound to come out clearly...

Next problem is which speakers will fit in there... The cardboard circle I stuck on there is 70mm in diameter, or 2.75", there's not much in the way of speakers that size to choose from. However...

The speakers in the corners of the dashboard in the X350 XJ are about 65mm in diameter, roughly... and they are Alpine branded units, and they sound pretty good in the XJR!




The next challenge is finding a speaker grill 70mm in diameter, that will match the bass speaker lower down. So far I have not found one in a suitable size that won't look like crap...

But if we can find a grill, then we have some speakers that should be OK.

There are also some Bowers & Wilkins 80mm single cone midrange speakers available, in the same yellow kevlar design, from the Volvo XC90 and S90, I would like these because they will visually match the bass speakers, but 80mm will be a bit tight to fit in the available space in the door cavity...

So that's about it... I need to find a 70mm speaker grill to match, I need to test out the XF/LR2 amp, or I need to throw some money at Mobridge...

 

I have changed the speakers and tweeters in my 08 Alpine to B&W slight better sound but still to bassy with no midrange would really like to see what you decide to do

 

Thanks for the write up on the sound system. Very useful reading to anyone looking into changes.

If you do put in the rear tweeter, could you just shut off the rear balance when you have a rear passenger?

I've never had music on with a rear passenger in the car as conversation tends to rule in that situation.

 

I am in the middle of switching from an 07 XKR with the Alpine system to a 10 XKR with the B&W and I actually reckon that the Alpine is better. Even with the bass and sub on full it doesn't seem to have the same bass output as the Alpine system.

I did switch the output to each individual speaker and also stuck my head in the foot well to see if the sub was working and it all seems to check out OK.

The iPod cable is missing so I couldn't check what the sounds quality was like through the ACM but the radio sound quality is poor.

 

My Peugeot 207 (2007) has a lot better sound then the Jag with the OEM speakers and radio. The car has also only 4 speakers and 2 tweeters but the sound is so much better.

So one can wonder how Jaguar could get it so wrong!

 

These look interesting. Instead of a big paper cone maybe these would work.
https://www.parts-express.com/tang-b...eeter--264-866

Response down to 700hz.

 

Pulling fuse 19 helps improve the sound system dramatically.

 

This is a very worthwhile project, thanks for diving into it Cambo!

Even the B&W system is in need of substantial improvement; it's fine for acoustic or classical music, but anything with electric guitars is absolutely unbearable. However, I would caution against a couple of the proposed remedies.

First, you should give some consideration to creating a sound stage. Music is recorded and engineered to be listened to as if you were in a live audience with the band performing on a stage in front of you. This is fundamentally different from cinema, which is recorded and engineered to immerse you in a movie. I will concede that there are a couple of surround sound music formats out there, but they're pretty rare.

The point is that tweeters in the rear of your vehicle would probably do more harm than good. High frequencies are easy to localize and this would destroy your sound stage. Also, without a custom DSP it would be impossible to get the time alignment right on your rear tweeters, which would detract from the realism and clarity of your music. Lastly, many of your proposed locations are significantly off-axis, which means that frequency response would decline rapidly as you move up into higher frequencies, creating an unnatural and "peaky" sound. I've had some excellent car stereos before and when set up properly, you would never even know that I don't install any speakers behind the front seats except a subwoofer.

The midrange is definitely where this system is lacking, so adding midrange speakers seems like it would be a good solution. However, there are some problems with this approach as well. First, as you have mentioned, there are not many potential locations for them. The position on the door panel that you proposed would be a good location, but if you were to surface mount them, they would be about 45-80 degrees off-axis, which again changes the audible response throughout the frequency range.

Personally, I believe that the stock door speakers (B&W or Alpine) could probably extend into the lower-to-middle midrange where this system is weak; approximately 300hz to 800hz or so. The problem is that the stock head unit only allows control of Sub, Bass, and Treble frequencies and none of these filters are centered anywhere near this range so there is no way to EQ it!

One of these day when I have a few less projects around the house that need funding, I do plan to implement what I believe to be the most likely solution: the previously mentioned mObridge DA3 Pro and a couple of aftermarket amplifiers. It will be expensive, but I think that the stock B&W speakers could do a good job if EQd and timed correctly.

Just my humble opinion, and by no means the end-all source. I really hope that somebody tackles this project and reports back on their results!

 

I don't get it!?

My peugeot 207cc from 2007 is a much cheaper car and with a similar set up but the sound is so much better!? Why would some new Alpine or Pioneer speakers not improve the sound quality?
I bought other tweeters(JBL) a week ago and tested one instead of the OEM and I found the sound improving.
Would a couple 6,5" speakers from JBL or Alpine not improve the sound substantially?

I have a small plan of disconnecting the rear speakers and connect them to a pair of 9x6" speakers in the rear shelf with a small amp. Am I stupid thinking that is a good idea?:-)

 

Cambo,
I will suggest some hardware changes.
However, ultimately you will discover the issue is the erroneous software.

I should have the software solution ready this week.

I suggest you do the following before making any irreversible mods to the driver housing. Go to a proper hifi shop, ask to listen to the B&W speakers you see with aluminum dome tweeters, with the best amp and source they have in the store. They will be surprised because one would not normally put a mid-level speaker with a top-tier electronics package, ask to be indulged.

If you still find the tweeter to be disagreeable, go ahead and change it. But not with another tweeter- that is also a problem. Change it with a midrange.

Flyc2c is on the right track.

The one massive difference between tech from a decade ago when our sound systems were designed, is the improvement in 'full-range mini speakers' due to the insane demand from tiny blue tooth boxes. Such as a little Bose boombox, its a marvel for the 2" drivers it uses.

One thing you must look into is if there is any way of providing some cabinet volume behind the driver. So, is there room in the pillars to run a small tupe or even leave the back open. this will be crucial in deciding what driver you go with. And the big reason why our sound system sounds bad. What they did is use DSP to overcome the absence of cabinet volume, so that they could stick a driver in its own box and use it across all different models and get the same sound. Historically, the entire cavity inthe door for example is used as the baffle.

 

This is what you want to look out for.
Here is a 2" driver that looks like the perfect candidate, until you look beyond the top line.
Look at that green line on the graph, its the 60 degree off-axis response- its disgusting. https://www.parts-express.com/pedocs...spec-sheet.pdf
You will only be able to listen to the driver off-axis the way it is mounted in he car from the factory!!
Note very few drivers if any have good response when you listen to them off-axis, (from the side) so one thing to consider along with a new driver is changing the angle of the driver more towards the driver- the difference is not subtle.

 

Thanks everyone for your inputs, all are appreciated.

In the meantime (with a bit of help from our friend in NZ, u102768) we could identify the different software versions between the Alpine and the B&W systems.

As the factory amps are all "the same" with continuous supercession, the only difference is the software.



Later this week I will have a chance to flash the earlier Alpine software into my XKR, see what sort of improvement that makes.

I've also bought a B&W/Alpine Surround amp from an XF/LR2, so that will be the next test. It's going to take a couple of weeks to get here though.

I won't claim to be a car audio expert. But after retrofitting the factory Premium system to a dozen JLR vehicles (X-Type, F-Type, XF, LR2, LR4, etc) I think i've got a pretty good feel for what sounds good, and what works.

The factory car audio is always a compromise, the speakers are never in the ideal location, all the marketing claims about "B&W worked on speaker location in the car" is BS. The speakers were put where the interior designers allowed space... looking at the factory location of the midranges in the F-Type, they aren't ideal either, but they make a big difference nonetheless.

The B&W Surround in the 2008-2011 XF is pretty bloody good, the Alpine Surround in the LR2 a close 2nd. These are my benchmarks. They both have the same hardware (head unit & amp), same speaker count, and similar sound. From the same era as the X150 too. I'm not expecting 2017 sound from 2005 hardware...

In the XJR, those two ~60mm midrange speakers on the dash take care of just about everything, you can barely hear the tweeters in the front doors, so it's obvious that this is what's missing from the X150.

So let's see where it goes from here.

I'm not convinced about adding tweeters to the rear anyhow, the thought of cutting the holes to mount them (in any position) makes my stomach turn... but that'll be the same issue with adding midranges to the front doors too so i'd better man up.

Adding midranges to the front really depends on getting the XF/LR2 amp working and how it sounds. Once that's sorted i'll have to make up a temporary wiring harness to split the bass and tweeters in the doors, and add the mids, for testing, to see how it sounds, before doing something irreversible. The mids will have to be wired in paralell to the tweeters (same as the factory setup in the XF/LR2).

 

Yes the problem is the aim of the speakers, they are pointing at our legs!

Those ones you linked to have that drop-off at 10KHz, but that range & above would already be well and truly covered by the tweeters in the A-pillars..

 

The issue with the door speakers (workhorse) is simple.
When you have a wok, all you serve is stir fry.
B&W has no experience in car audio, and the choice of kevlar (their trademark [wok] midbass driver) is simply wrong.
As you know from many cars the overwhelming choice is paper, because it can simply do more in a car environment.

2. points:
large magnet is not a good sign, it shows that it was not a driver made for car audio. And very wrong for a sports car. Neodynium mags is what every high-end car audio manufacturer uses, thus lightweight and more efficient paper cone that requires fraction of the magnet size.

Secondly, if you can measure if the wires to the door speaker or tweeter are indeed getting full frequency. My guess is not! I suspect that the frequency manipulation and attenuation is going on in the DSP. The capacitor may be used as way of avoiding phase-shift.

If it is getting full frequency, just take the leads from the speaker at foot level and piggy back to tweeter so as not to worry about DSP etc.

 

Yep, for sure.

Here's an interesting example. On the left is the bass speaker from the LR2 with "Alpine" Surround, on the right the one from the XF with B&W Surround.




As you can see, apart from the cone construction, they are all but identical, both made by PSS.

I put the B&W ones into an LR2 as part of a Surround retrofit, they did sound "stronger", but it may have been an excellent placebo effect. We've also put these B&W ones into an F-Type to replace the god-awful factory bass speakers in the doors, and it was a huge improvement in that car. Also put them in a 2014 XF, replacing the factory "Meridian" speakers, again it was a noticeable improvement. (obviously the Meridian is not made by Meridian, actually PSS again).

I know, it's a bit of a joke actually (Boris The Blade didn't put the humour across enough?)

One interesting thing to note, is that the Alpine branded bass speakers in the X-Type and X350, the ones with the blue-colour paper cones, have a tiny magnet on them... but they sound pretty good regardless!

These ones https://www.ebay.com/itm/JAGUAR-XJ8-...4/332009282557

I don't have the necessary equipment to measure the frequency spectrum, but listening to the bass speaker in the door of the XK, there's a lot more midrange coming out of it than the bass speakers in the LR2. Also there is only one channel from the amp to each door, so it has to be the full range (less a lower cutoff) in order for the tweeter to get the highs. There's no external crossover, just the cap in the tweeter.

The way it's wired from the factory, the tweeter is paralell to the bass speaker on the same channel. If adding mids to the same channel we'll need a crossover of some sort, otherwise that mid will get the low-range that's going to the bass speaker as well. This is solved in the XF/LR2 by having two channels to the door, one for bass, one for mid/high. There will be some frequency limitation on the mid/high channel with that amp, as the mid/high speakers in those cars definitely do not get lower tones, and there is no cap or external crossover on the mids in those cars.

Regarding the capacitor on the tweeter, I went through this when I did the Premium Sound retrofit on my X-Type. The factory tweeters have the cap on them. I used aftermarket tweeters that didn't have a cap. The sound was awful, because the tweeter was being overdriven, being fed midrange tones that it couldn't handle. I took the caps off the factory tweeters and put them on the aftermarket ones, big improvement, no more distortion.

 

This is very sad and disappointing. It appears that the only thing Bowers and Wilkerson about that driver is the change in specification of the cone material and dustcap, so it merely looks like a signature B&W driver. The really bad thing about this is what you already proved via demonstration. The motor designed for the cone material will sound infinitely better than one being used arbitrarily with a Kevlar cone.

We have just hit a brick wall.

 

Perhaps B+W just had input on the 'tune' of the speakers, similar to Alpine doing it in years previous. Kind of how Dolby 'tuned' signals back in the day to sound different.

Speakers look made by the lowest bidder so why not just upgrade them to something mid grade and go with a co-ax or tri-ax speaker. I went with some mid grade Poly co-axial's for the rear shelf on my Lincoln LS and it made a huger difference over the stock 'premium' paper cone speakers that the OEM installed. Picked up sound quality all over. Back glass acts like a reflector / projector so aiming wasn't as critical.

My passenger door speaker is buzzing so a speaker upgrade is upcoming.

Cambo, perhaps look at tweete in the C panel vs. the leather quarter. That way if you don't like the result it's easy enough to cover up (or just leave them hidden behind the material so it 'looks' stock).

 

I guess it's more of a branding/marketing thing, than actual technical input. I'd like to blame B&W for the software in the amp though!

Not sure I follow what you mean here. I've heard both of those speakers in that pic, in the exact same vehicle (the LR2) and they both sound "good".

Actually the 100mm midrange/surround speakers in the XF and LR2 are the same in that the B&W version is the same everything except for the cone & dust cover. I put the B&W 100mm ones in the LR2 in place of the standard ones, and it sounded good, i'd say even better than the standard ones. I never touched the software in the amp...

I don't think so.

There are a number of different OEM bass speakers from "premium" systems that will bolt straight in, some of them will need wiring adaptors, but I have the parts on hand to make those. Take your pick from;

B&W from XK, yellow kevlar
Alpine from XK, black paper
B&W from XF, yellow kevlar
Alpine from LR2, black paper (not the same as the XK ones)
Alpine from X400/X350, blue paper
B&W from X351, black kevlar

All of them will fit, it's just a question of which ones will be the "best" with the software in the amp, be it Alpine or B&W...

I guess they also had a hand in the software. But it's interesting for me that there is nothing B&W in the touchscreen, whereas in the XF there is a B&W logo in there.

LOL you have summed up the entire automotive industry

When I did the Premium Sound retrofit in the X-Type, I used some highly reputable aftermarket splits, and the sound was pretty disappointing if i'm honest.

Later on I helped another X-Type owner with the same retrofit, he bought the same speakers, and he was also disappointed. Later on he got a full set of the blue Alpine door speakers, and matching tweeters out of a wreck, and put them in. It sounded a lot better.

So after that, I developed a theory, that OEM speakers sound better with OEM amps, aftermarket speakers sound better with aftermarket amps. Another friend of mine who is a car audio installer, has said the same thing (he'd never put it in writing though, his livelyhood depends on selling aftermarket speakers...)

Well whatever you put in, get some of my adaptor cables so you don't have to cut wires. https://www.jaguarforums.com/forum/p...150-xk-192057/

I had another listen to this system on the way to the office today, I think doing anything for the rear stage in this car is now at the bottom of the list...

 

I like that you sourced stock pigtails. On the LS I resoldered the OEM connections off the old speakers onto the new ones. If you ain't cheating you ain't trying hard enough.

 

It may be different today, but years ago when I played with these things, it came down to impedence matching. The aftermarket stuff, at the time, was 8 ohm at some reference voltage, while the OEM stuff was ‘different’ and varied by manufacturer. So you could never get a good sounding mix of the two.