3rd Gen rear door 6.5" speaker upgrade

Snowden

New member
I decided to update my stereo head unit and speakers in Snowden. There are a few threads on this subject so rather than try to pick one and post with I'll start a new one simply to show a successful rear door 6.5" mod. Most of the threads out there just go back and forth about whether they would fit or not and the general consensus is to stay at 5.25" to keep it safe while only a handful of guys report 6.5", and even 6x9, but little to no detail on specifics.

For my upgrade the fronts are the same speaker (Kenwood KFC650 - 3Way) and those were literally plug & play so I'm not adding write-up about the fronts. For my head unit I went with a Sony Double Din WX900BT model. No need for me to post up regarding the HU there are plenty of threads about the HU swap. Any questions about it though pls feel free to ask.

So... For the rear door speakers. Did a ton of research on this before diving in and what became clear is that you need to get the right balance between how deep they mount, how wide they are, and how much they protrude. The Kenwood KFC650 had the shallowest mounting depth at under 2" in this size and competency range.

I did first try the JBL GX602 but while they did barely fit in the front doors they would have required metal trim in the rear doors in order to keep them low enough that the window didn't hit them when rolled down. I wanted to stay away from metal trimming. The other issue I discovered was that they are 2.3ohm and the HU calls for 4-8ohm so just as well anyway.

Once you decide on the speaker it is first necessary to mod up a spacer piece. It's possible to order them on-line but I found a cool suggestion; to simply Dremmel them out from cheap cutting boards (under $2. each !). Holding a steady Dremmel isn't easy with the material but I did manage to get it well enough for sealed fitment.

I mounted the spacers using the original factory mounting points in the door. Two of which I also used to pick up two of the mount locations on the speaker frame. The remaining two speaker mount locations didn't align with the factory position so I drilled and screwed those into the spacer. In addition I added Tacky Butyl Sealant tape to both the spacer to door contact and the speaker to spacer contact. This stuff is great and not only seals it tight but also has a holding power to it.

The final fit is perfect. The windows don't touch the speaker magnets and the door panels clear the fronts with room. The final product is amazing with quadraphonic sound in 6.5". In fact when I installed the HU I removed the factory amp with the intention of adding an aftermarket. But with 20RMS on this Sony and the 3Way 320w (max rated) Kenwood's, I don't think I even actually need to add an amp after all. The sound is so deep and rich and it completely fills the vehicle. By the way, if you are doing a stereo upgrade be sure to buy the Metra harnesses, it's the only way to fly...

Here is the original 4" next to the new Kenwood KFC 650.
KFC650 install 3rd Gen - 001.jpg

This is the factory mount/spacer that the 4" comes out of. Remove this.
KFC650 install 3rd Gen - 002.jpg

New spacer installed.
KFC650 install 3rd Gen - 003.jpg

Final fitment 6.5" rear door.
KFC650 install 3rd Gen - 004.jpg
 

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I've been looking to do this and I really appreciate what you've done here.

I have a 5 channel pioneer amp and have been waiting to do my rear speakers til I could figure out how to do 6.5".
Thanks for the help!
 
To amp or not to amp.....

So you are running these without a amp, and think they are good enough without one? Looking to upgrade speakers all around.

This audio stuff all comes down to personal preferences. My age (older guy) and music taste plays a roll in my preferences. I do have a discerning ear and appreciate crankable tuneage but I don't need subwoofers and or volume requirements to an unrealistic level simply for the sake of being able to annoy the car next to me at the red light. As long as I can crank it clean and enough to shut up any annoying passenger I'm good. What I missed were the aftermarket systems of our muscle cars in the 70's/80's. I had a JVC/JBL combo system in my 73 Camero that bumped.

But those head units had onboard power that is a thing of the past. That's all I wanted to achieve again and this set up did that for me. 20RMS is at the top of the onboard power game these days but after i hooked it all up it seems like enough horse power for me already. But I agree with [MENTION=120787]Bijan[/MENTION] that, if you want to, sure go ahead and amp. The extra power helps add to how clean music comes through and it isn't all about volume intensity.

My point though was that, originally I thought I was going to add that little Alpine inline amp unit for $149. but I found this set up throaty enough for me. And no underpowered distortion that I could tell. Pat Benetar sounded tasty for damn sure... But maybe after I actually drive the rig at freeway speed maybe I'll change my mind.
 
Great job!! Now you have 4 tweets up front. I was wondering how they would sound. Glad they sound great. Let us know how they perform with noise and exhaust drone. I am a big fan a clean sound. I am sure a small amp will do wonders. You can always seal the door to get the most from those drivers. Either way, sweet mod!!
 
Great job!! Now you have 4 tweets up front. I was wondering how they would sound. Glad they sound great. Let us know how they perform with noise and exhaust drone. I am a big fan a clean sound. I am sure a small amp will do wonders. You can always seal the door to get the most from those drivers. Either way, sweet mod!!

Thanks Rally. Just to be clear though I didn't hook the factory tweets back up I just kind of thought that wouldn't work or something...(?) but I wasn't going for the Componant set up. And the metro wire harness sends it all to the base speaker. Once you get the door panel off you'll see the factory tweeter robs its signal from the main two wires after the fact anyway. Yes I do agree; I may go back in and add the insulation to the door panels DTR...
 
But I agree with [MENTION=120787]Bijan[/MENTION] that, if you want to, sure go ahead and amp. The extra power helps add to how clean music comes through and it isn't all about volume intensity.

My point though was that, originally I thought I was going to add that little Alpine inline amp unit for $149. but I found this set up throaty enough for me. And no underpowered distortion that I could tell. Pat Benetar sounded tasty for damn sure... But maybe after I actually drive the rig at freeway speed maybe I'll change my mind.

A properly tuned amp will always make a system better. An improperly tuned amp can make a system sound like total shit. I've seen guys turn up the gain on there amps to distorting levels. Sure, it's loud but it sounds like crap. You want to find the balance of loud and clean. It's more of an art then a science and everyone's ear is different. So my proper tuning may be different than your proper tuning with the same set up. But if it's distorting at all it's usually because people are over-powering the speakers.
 
A properly tuned amp will always make a system better. An improperly tuned amp can make a system sound like total shit. I've seen guys turn up the gain on there amps to distorting levels. Sure, it's loud but it sounds like crap. You want to find the balance of loud and clean. It's more of an art then a science and everyone's ear is different. So my proper tuning may be different than your proper tuning with the same set up. But if it's distorting at all it's usually because people are over-powering the speakers.

Not all amps are tuneable. This was all I was thinking of adding. Just something to 'give you 11 when most only go to 10' , to quote a line from Spinal Tap. 45RMS per channel x4, a sweet little set up for another buck-fifty.

"Alpine - Power Pack 180W Class D Bridgeable Multichannel Amplifier with High-Pass Filter - Black" $149 at BB. $149 at CF.

EDIT: further inspection reveals this Alpine PP amp is in fact tuneable. Independent Front / Rear gain controls.
 
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Not all amps are tuneable. This was all I was thinking of adding. Just something to 'give you 11 when most only go to 10' , to quote a line from Spinal Tap. 45RMS per channel x4, a sweet little set up for another buck-fifty.

"Alpine - Power Pack 180W Class D Bridgeable Multichannel Amplifier with High-Pass Filter - Black" $149 at BB. $129 at CF.

While it may not be user tuneable it's tuned. Alpine just has already set the gain for you. I trust them to not make my set up sound like crap. lol
 
Nice job, looks pretty similar to what I did except with MDF. Only need a spacer to make them fit really, most speakers are pretty small in profile nowadays.
 
I decided to update my stereo head unit and speakers in Snowden. There are a few threads on this subject so rather than try to pick one and post with I'll start a new one simply to show a successful rear door 6.5" mod. Most of the threads out there just go back and forth about whether they would fit or not and the general consensus is to stay at 5.25" to keep it safe while only a handful of guys report 6.5", and even 6x9, but little to no detail on specifics.

For my upgrade the fronts are the same speaker (Kenwood KFC650 - 3Way) and those were literally plug & play so I'm not adding write-up about the fronts. For my head unit I went with a Sony Double Din WX900BT model. No need for me to post up regarding the HU there are plenty of threads about the HU swap. Any questions about it though pls feel free to ask.

So... For the rear door speakers. Did a ton of research on this before diving in and what became clear is that you need to get the right balance between how deep they mount, how wide they are, and how much they protrude. The Kenwood KFC650 had the shallowest mounting depth at under 2" in this size and competency range.

I did first try the JBL GX602 but while they did barely fit in the front doors they would have required metal trim in the rear doors in order to keep them low enough that the window didn't hit them when rolled down. I wanted to stay away from metal trimming. The other issue I discovered was that they are 2.3ohm and the HU calls for 4-8ohm so just as well anyway.

Once you decide on the speaker it is first necessary to mod up a spacer piece. It's possible to order them on-line but I found a cool suggestion; to simply Dremmel them out from cheap cutting boards (under $2. each !). Holding a steady Dremmel isn't easy with the material but I did manage to get it well enough for sealed fitment.

I mounted the spacers using the original factory mounting points in the door. Two of which I also used to pick up two of the mount locations on the speaker frame. The remaining two speaker mount locations didn't align with the factory position so I drilled and screwed those into the spacer. In addition I added Tacky Butyl Sealant tape to both the spacer to door contact and the speaker to spacer contact. This stuff is great and not only seals it tight but also has a holding power to it.

The final fit is perfect. The windows don't touch the speaker magnets and the door panels clear the fronts with room. The final product is amazing with quadraphonic sound in 6.5". In fact when I installed the HU I removed the factory amp with the intention of adding an aftermarket. But with 20RMS on this Sony and the 3Way 320w (max rated) Kenwood's, I don't think I even actually need to add an amp after all. The sound is so deep and rich and it completely fills the vehicle. By the way, if you are doing a stereo upgrade be sure to buy the Metra harnesses, it's the only way to fly...

Here is the original 4" next to the new Kenwood KFC 650.
View attachment 232903

This is the factory mount/spacer that the 4" comes out of. Remove this.
View attachment 232904

New spacer installed.
View attachment 232905

Final fitment 6.5" rear door.
View attachment 232906



What did you use for the material for the new spacer?
 
He mentioned he used 'cheap cutting boards', I guess you'd have to look for the thickness you need or simply double up thin ones?

Personally, I'd rather go to all this trouble for the front speakers, where all the action is! Luck and enjoy. :cowboy:
 
He mentioned he used 'cheap cutting boards', I guess you'd have to look for the thickness you need or simply double up thin ones?



Personally, I'd rather go to all this trouble for the front speakers, where all the action is! Luck and enjoy. :cowboy:



6.5" speakers I the front doors is easy. Not really any fab issues at all.


Sent from my iPhone using Tapatalk
 
What did you use for the material for the new spacer?

"Once you decide on the speaker it is first necessary to mod up a spacer piece. It's possible to order them on-line but I found a cool suggestion; to simply Dremel them out from cheap cutting boards (under $2. each !). Holding a steady Dremel isn't easy with the material but I did manage to get it well enough for sealed fitment."

Bought a couple of cheap Polymer cutting boards from Wallymart. $1.80 each. But as I also noted you have to be careful with the high-speed Dremel and sharp cutting bit with this material. You can see my edges aren't perfectly straight as it tried to get away from me and blaze its own trail.

The reason I ended up going this cheapo route was my cost/benefit ratio plummeted since Amazon reported the wrong spacer product would fit the 1998 4Runner. They were a complete waste of money by the time I received them because of that. These are the incorrect spacers;

https://www.amazon.com/gp/product/B007ZQGZWO/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

FWIW if I were doing this again I would probably order these below as this appears to be the correct spacer. They are for 5.25" so might require opening up a bit but one could use the Sander Bit instead of the aggressive Cutting Bit. YMMV.

https://www.amazon.com/1996-2002-To...83550693&sr=8-30&keywords=car+speaker+spacers

This really is not that difficult of a mod you just need to get the correct items. The important thing to note is that speakers are not actually all the same overall size in any one size category. As I noted for example; My original choice was the JBL but in the end they were too deep (without cutting the door to lower them away from the window) at over 2 1/4" plus their total diameter of the frame made them hang up on the door panels. The Kenwood's were shallower at under 2" (just enough) plus their overall diameter was smaller.

I disagree with the folks that say don't even bother with rear door speakers. All you have to do is sit in your rig and; fade to front, fade to center, and you will absolutely hear how much more the sound fills in all around. And since these are all the same size now you hear it that much more - IMHO.
 
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3rd Gen rear door 6.5" speaker upgrade

It's more of an art then a science...

Quite the contrary; setting the gain on an amp properly is done with math.
It should be measured and set to match the RMS of the components/speakers.
Google "How to set gain...", and you'll find plenty of threads/articles/videos on how to properly set gain.
 
def need this

Def a needed upgrade. riding in my 335 and hten in the 4runner... sound is horrible in comparison haha
 
I have Infinity kappa 6.5s in front. Is it a no-no to mix and match brands?

Edit: The Kappas have a mounting depth of 2.125. With the mounting bracket on there do you think these will fit?
 
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Anybody have issues with the large magnet in back of the speaker and the window not going all the way down? Havent seen anybody address this?
 

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