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Discussion Starter · #1 ·
Hi everyone,

My wife just bought a 2002 SportX with only 7k miles...nice car.

We've purchased a Pioneer AVIC-N1 so my wife can have a Nav (she needs it everyday for her work (+ we're going to add rear LCD's for the kids on trips). We are only trying to maintain the stock sound quality or improve it a bit. We just don't want to go backwards. I'll be bypassing the stock amp(using the HU's amp), keeping the front speakers, and I plan on possibly changing the rear speakers and that's where the question comes in.....

First, I've searched exhaustively here and pretty much understand all the issues with the stock speakers/amp/HU on the sedan, but even though I can find similar questions, I can't find any answers specifically addressing the specs on the stock rear speakers in the SportX. I understand what are back there (2 - 1" tweeters, 2- 5 1/4 midrange??, and a small woofer - size?), but I don't know the specs on them. Based on the wiring diagrams, the amp appears to be the same as the sedan, so I assume the tweeters and 5 1/4's are 4 ohm and the single woofer is getting both the right and left 2 ohm feeds.....but what is the spec on the woofer? 1 ohm, 4 ohm? Or can you tell without knowing how it is wired....or can anyone hazard an intelligent guess if you don't know for sure.

1 - What is the best way to deal with the rear speakers? Keeping in mind, minimal work and cost, and that I'm only trying to maintain the stock sound quality. If it comes out better, that's fine too, I just don't want it worse. :)

2 - Are there any 5 1/4's that I could replace the stock one's with that would provide bass equal to the stock 5 1/4's and separate small woofer setup...in other words mimicking the setup of the sedan with its 6X9's.

3 - The reason I want to know what the stock woofer is to figure out if it is possible just to run the HU's built-in amp to the rear stock tweeter and 5 1/4 speakers, and run the sub woofer pre-amp lead from the HU to a small amp in the rear to power the existing woofer. Does this make any sense. If it does, would you need a two channel amp to run the stock woofer?

...and then there's the crossover issue for the front and rear main speakers and tweeters.

Any and all help is appreciated. Thanks in advance.

BTW, you guys have created a great resource for IS300 owners. It's a real gem.

Bill Pryor
 

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Discussion Starter · #2 ·
...more info for SportCross owners

I have made a little more discovery and thought I'd add the info to help any other SportCross owners that also can't find answers about their speakers. It still kind of amazes me that after a couple of years of SportCrosses being around that at least one of the experts up here hasn't worked on a SportCross.

Although I have not removed the headliner to look under the "tweeter" grills, they appear to house speakers bigger than 1". Also, on the wiring diagram it indicates these are squawkers(for those that don't know what these are, like me, they are mid-range speakers) and not tweeters.

Based on this knowledge, I've decided to install 5 1/4" components in the back, and cut the little woofer out of the loop. This is going to be a real pain since the headliner will have to come at least partially out to get the squawkers out and the tweeters in, and that doesn't look like an easy task. I'll also add a passive crossover up front to mimic the stock amp's crossover.

Although this will not be ideal, it should sound decent now, and it gives me the option of relatively easily adding an amp and sub in the rear if I want/need to (I'm going to run the RCA's, control wire, and power while I have the car torn up).
 

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You have to consider that the number of SportX owners is very small. IS300 isn't exactly a great seller and the SportX takes only a fraction of those.

This thread could become useful to the other SportX owners. Could you take pictures of the work that you do and of the stock components? Please, record resistance indicated on the speakers.
 

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Discussion Starter · #4 ·
pics

You have to consider that the number of SportX owners is very small. IS300 isn't exactly a great seller and the SportX takes only a fraction of those.
I realize that, though I didn't have any idea just how small it is. I just figured that this forum is so active that someone would have done it by now. Anyway, I'm glad to be the guinea pig. :)

As far as the pictures and resistance indicated on the speakers, will do. I had already planned to do the pictures. I'm about ready to start, and it looks like it is going to be a much larger job than on the sedan. It appears that the entire interior cover behind the seats is only in a couple of pieces, not counting having to remove the headliner to get to the tweeter location.
 

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Re: pics

bpryor said:
You have to consider that the number of SportX owners is very small. IS300 isn't exactly a great seller and the SportX takes only a fraction of those.
I realize that, though I didn't have any idea just how small it is. I just figured that this forum is so active that someone would have done it by now. Anyway, I'm glad to be the guinea pig. :)

As far as the pictures and resistance indicated on the speakers, will do. I had already planned to do the pictures. I'm about ready to start, and it looks like it is going to be a much larger job than on the sedan. It appears that the entire interior cover behind the seats is only in a couple of pieces, not counting having to remove the headliner to get to the tweeter location.
Any info you can share will be greatly appreciated. I will add that, that is useful to a sticky for other X owners. I have yet to see one let alone work on one.
 

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Discussion Starter · #6 ·
Info

Any info you can share will be greatly appreciated. I will add that, that is useful to a sticky for other X owners.
Sounds good. I'll gather as much info and pictures as I can.

I have yet to see one let alone work on one.
You're not alone. When my wife bought this car she was actually looking at another type of car, spotted the IS, and we both said, "What's that?". She fell in love we it, and off she went. We both are pretty Leuxus savvy and knew all about the IS300 sedan since it was released(I had a GS400 at the time), but neither of us even knew the SportX existed. Lexus' best kept secret I guess.
 

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Bill,
Keep us informed! I have a 2002 Sportx and am considering an aftermarket install (leaning towards the Kenwood ddx7015), and I wasn't sure what the stock rear speakers were. I knew the Sportx has a subwoofer that the sedan doesn't have, but I didn't know if it could be used with an aftermarket setup, or even if it was worthwhile to try.
Good luck with your install.
(I've owned my Sportx for one year now, and I've only seen two other Sportx's on the road in that time)
Stan
 

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Discussion Starter · #8 ·
Using stock woofer

Hi Stan,

I'm hoping the stock sub is usable too, but I don't have my hopes too high. Unless the crossover in the stock amp for the SportX is different than the sedan, then I would guess that the sub that's in there isn't really optimized for lows, since with the stock crossover(if same as sedan) it's being fed both mids and lows.

Hopefully when I get the pictures, and specs off of it, the experts here can let us know if it would add much to the system when using an aftermarket amp and crossover with it.

If things go to plan I'll have the pictures and specs up here Saturday night.

Bill
 

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Discussion Starter · #10 ·
Update

Hi Stan...and other interested parties,

I haven't forgotten to post, but to no surprise, things have not gone as planned. Besides distraction issues, the job at hand has turned out to be a much larger one than I originally thought. After examining in detail what was going to have to be removed to get to all the speakers in back(all side liners, floor liner and headliner), I decided to change my plan of attack. Instead of working on changing the speakers in the rear first, I'm installing the AVIC-N1 and a GEX-P910XM XM tuner first, patching into the stock wiring from the stock amp (which I removed....what a pain). After I get this completed and hooked up, I'm going to make a decision on the rear speakers depending on the sound using all the stock speakers. My decision would be a lot easier if I had access to workshop manuals to give me some guidance in taking the rear apart....it is not obvious.

Of course, even using the stock speakers, it's not really as easy as it sounds. I still do not know the impedance of the stock woofer. I'm guessing it's a dual coil 2 ohm, based on what the stock amp does in the sedan, but I don't know for sure. On top of that there's a "amp+" connection directly between the stock radio and the woofer, which does not exist on the sedan at all. I don't know what that is for either(if anyone knows, please let me know). What I have done is bought a tiny 100 watt 2ch RockBox amp to run a small separate woofer, whether it ends up being the stock one, or a small aftermarket one mounted in the stock location. The problem is that I can't hook up the amp to the stock woofer without knowing its impedance(the RockBox is designed for 4ohms)....which means unless I can find out the impedance of the stock woofer through some other means, I have to pull the back apart, whether switching the speakers or not, if I want to hook up the RockBox. If I end up having to do that, I might as well go all the way and put the components in too(which I already bought).

BTW, I'm mounting the RockBox where the stock amp was. It fits easily since it's only about 1/3 the size of the stock amp. There is access there to the speaker wires to the back, and it's a easy run to the HU for the control wire, plus the battery is a short shot for power, and the ground point is right there too.

I am taking pictures as I progress, but since I can only work on this a couple of hours here and there, it could be some time before I finish.
 

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It seems that the woofer has a built-in amp. I think the Amp+ wire is the remote turn-on wire.
 

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Discussion Starter · #12 ·
Maybe.

Hi vlad_a,

It seems that the woofer has a built-in amp. I think the Amp+ wire is the remote turn-on wire.
I considered that but I couldn't understand why it would have leads coming from the main amp, and an amp in the woofer itself. Is it possible it's some sort of booster on top of the stock amp's output? If so, my idea of hooking up an aftermarket amp to the stock woofer is out the door, and I'm back to ripping the back out, which is getting pretty obvious that's what I should be doing....sigh.

Bill
 

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Another close look at the diagrams revealed following:

Front - 4 ohms
Rear - 4 ohms
Woofer - 2x 2ohms

Why? Look at the pin numbers. Sedan's output is identical to Sport-X. The only difference is the 2 channel woofer output is combined by a module inside of the Sport-X woofer into one. Sedan's rear speaker (mid & high) output is split into squaker/tweeter in the Sport-X.

Something tells me if you send a 4 ohm capable output to WL- and WR+ on the woofer and short out WR+ and WL-, you will get a 4 ohm load. Stock amp must be disconnected (not an issue, as you have already removed it).
 

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Discussion Starter · #14 ·
Sedan's output is identical to Sport-X. The only difference is the 2 channel woofer output is combined by a module inside of the Sport-X woofer into one.
I had been going on that assumption, I just wanted to confirm by seeing the woofer to make sure. I hadn't checked parts numbers to see if the amp is identical between the SportX and sedan, though I figured they probably were.....but since the HU isn't identical, I was thinking the amp might be different too.

Something tells me if you send a 4 ohm capable output to WL- and WR+ on the woofer and short out WR+ and WL-, you will get a 4 ohm load.
Question 1: What is the risk(s) in trying this?

Question 2: What about the "amp+" connection? Will the woofer still work without it?

Thanks for the help vlad_a.

Bill
 

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You're welcome! :D

Amp+ would send a positive 12V when the headunit is on. Your new headunit should have amp remote wire. You should be able to use that.

The risk of trying it out is buring up your amp and, possibly, the subwoofer.

BTW, how is the Sport-X headunit different? I've never got to see one.
 

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Discussion Starter · #16 ·
Your new headunit should have amp remote wire. You should be able to use that.
Yep, I've already run that to the RockBox, so I guess I can just branch off and splice into the Amp+ wire.

The risk of trying it out is buring up your amp and, possibly, the subwoofer.
I figured the might be the answer. :cry: I think I am moving closer to the conclusion that I just have to bite the bullet and pull the rear apart. I've mainly been resisting because I don't really have the time, but if I don't have a real choice....and it obviously is going to be the better solution sound-wise.

BTW, how is the Sport-X headunit different?
I only meant because it has the "Amp+" connection. I was assuming that the sedan version doesn't have one...but maybe it does and it just isn't used.
 

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bpryor said:
...I only meant because it has the "Amp+" connection. I was assuming that the sedan version doesn't have one...but maybe it does and it just isn't used.
It is likely the two are identical. That way, it is easier for the factory to manufacture only one version of the HU and amp than two.
 

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vlad-a,

vlad_a said:
Another close look at the diagrams revealed following:

Front - 4 ohms
Rear - 4 ohms
Woofer - 2x 2ohms
Does this mean we can likely keep the factory rear tweeter and squawker (4 ohms) with an aftermarket amp?
Thanks!
Stan
 

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soareyes said:
vlad-a,

vlad_a said:
Another close look at the diagrams revealed following:

Front - 4 ohms
Rear - 4 ohms
Woofer - 2x 2ohms
Does this mean we can likely keep the factory rear tweeter and squawker (4 ohms) with an aftermarket amp?
Thanks!
Stan
That's is my assertion. Just don't send any low freq to the squaker/tweeter. In many amps you can adjust the cut-out frequency. I believe Lisnup65 recommended the cut-out range for sedan's mid/tweeter speaker to be set at 1KHz. Same should be true for the Sport-X.
 

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Discussion Starter · #20 ·
update

Does this mean we can likely keep the factory rear tweeter and squawker (4 ohms) with an aftermarket amp?
I think that is a definite yes from what I thought, and what I have confirmed.....

...but as a point of clarification, there are 5 1/4" speakers and approx 2" squawkers in the back, not squawkers and tweeters. There are no tweeters in the back of the SportX.

What I am assuming is the amp is crossed internally the same as the sedan, which from what I've read, that means they currently are crossed at 100hz high. Assuming that, and from talking to a local radio shop about this setup, he said there is likely a passive crossover between the 5 1/4's and the squawkers. What I am doing while trying the stock rears to see how they sound is installing 100hz caps on the stock set of wires feeding the rear 5 1/4's and squawkers(if I don't switch speakers first).....also, if this is the case, you probably can safely send the lows to the rear speakers if you completely disconnect the woofer....but I doubt it will sound very good, or they wouldn't have put the woofer in there in the first place.

Also, I missed on the wiring diagram that the woofer is indeed powered, plus it has the amp+ going to it, which pretty much conclusively means the woofer has an amp in it.....so, this pretty much rules out hooking up an aftermarket amp direct to the stock woofer. Another thing I found was a diagram in the service manual that shows the woofer and "box" that it's in. It's not totally clear, but the picture looks like there is a plastic odd shaped box filling the back corner behind the woofer.
 
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