I have a '04 sedan with base audio which I want to upgrade, preferably without the added expense of new amps or a significant re-wiring job. Originally, I thought about doing this relatively simple tweeter replacement only, but instead would like to try replacing all front components while retaining the stock base audio head unit. After searching, I still have these questions:

Q1.) I'm pretty certain the sedan tweeters are rated 4 ohm for both base or premium audio system. Also, I see that the premium audio Bose drivers are either 6 or 8 ohm, but what is the ohm rating of the BASE audio door drivers (panasonic drivers, I believe)? I saw somewhere that the Base driver rating was different than the Bose, but I can't find an actual ohms rating for them. Hoping 4 ohm. If anyone with a manual or door panels off and an ohm meter in hand can confirm, it would be great.

Q2.) Depending on the stock base audio driver ohm rating, I may try Polk Audio db6500 components. I know the drivers will fit, but there is still a question whether these tweeters will fit under the stock grill without modification to the door cutouts. Don't really want to mount on top of stock grills if I can avoid it. Since the ex3560 component set and ex3500 tweeter set have been successfully installed by others, I know there is a minimum depth of 9/16" in the door cutout (each has a tweeter flush mounting depth of 9/16"). But the flush mounting depth of the db6500 tweeter is much greater, 1-1/4". I have found only one reference to the depth of the sedan's tweeter cutouts which suggests 3/4" is the max depth for a replacement tweeter. More detail about this question can be found in Upgraded my Bose system, very easy!. So if someone with their sedan tweeters removed could be kind enough to actually measure the depth of the tweeter cutout to verify max depth, that would be a big help.

Q3.) If the base audio head unit cannot power the new components sufficiently, I'll have to add an amp to power them. At that point, I'll probably just give in and add a new powered sub as well. So, I am also trying to find an easy way to add a new amp in the rear (where the Bose amp goes in the premium equipped G) by using the car's stock wiring harness, something that may work if Infiniti uses the same wiring harness in all sedans. For more info, see amplifier placement. Basically, I will need to verify that all sedans (i.e., base, premium, 6mt) use the same electrical system wiring harness, which may allow for simply hooking up existing (but currently unused) wires. Anybody here have a G35 wiring harness diagram for the various trim levels?

A call to dealer tech didn't do much, so any help from members in answering these questions is greatly appreciated! Thanks.

 

I installed a replacement set of Focal Utopias in the front doors (coupe).
The TN 51 tweeter is 2" dia. and 20mm. deep w/o the basket.
I was able to locate them in the factory location. I used a dremel tool and removed the outer OE mounting post. Used black silicone and dynamat extreme to form a good tight fitment.
The Focal 6.5 midbass wouldn't fit in either the OE basket or in the cutout in the door. Using a template and marking the door cutout i was able to fit the driver to the door by removing a VERY small piece if the door skin.
Caution! The new tweeters will be very bright compared to the take offs. It will take a head unit with time correction to center the stage properly.
The Panasonic speakers were 4 ohm. Focals are 3.7.
You'll need a crossover as well. One matched to the replacement components would be advised.

 

Thank you DbSQjunkie. Based on your install, it sounds like max tweeter depth is at least 15/16". That's a bit better than 3/4", but not enough for mounting the db6500 tweets behind the stock grills, ****. Do you remember if there was still any room behind them, or were you at the max depth? And, 4 ohms, great! I found so many "don't do its" when discussing replacement of the premium audio's front drivers because of the goofy Bose ohm ratings, I'm very pleased to see that the base audio drivers are conventional 4 ohm. That suggests the stock head unit will be sufficient to power replacement components with a db efficiency equal to or better than the stock components without the necessity of a new amp, right? The Polk drivers are 92db @ 4 ohms and tweets use a 2nd-order Butterworth external crossover so they should be very compatible if I can get them to fit. Not sure why you might experience any negative imaging impact with a front component swap if you already had tweets. Doesn't the stock head unit already compensate or use time correction to center the high stage properly when using the balance controls? What would change? Again, I appreciate your help.

 

More comments..
First there is no "time correction" in the OE headunit. Biasing the balance right will not soften the brightness of the tweeter.
Vocals will be way left. As mine is now, only to be corrected by real time delay technology.
Even though the efficiency rating on your component set looks good on paper your going to loose base level (not defination) by installing an upgraded driver. The new speakers will require amplification to accurately reproduce midbass tones. Truthfully the midbass drivers are too low in the door to produce good vocal staging. I haven't tackled this delima as of yet but will prior to my final installation.

 

dholly,

I just installed the DB6500's in my G35 Sedan tonight. The tweeters fit fine. I didn't use any of the mounting brackets for the tweeters. Just mounted them right to the stock grills.

I had to drill some holes in the 6.5" factory (white) mounting supports for the woofers. Other than that, it was a pretty painless install.

Man, what a difference in sound. There are high's that I haven't heard in my "G" before. Not sure the 6.5's improved my low end sound, but they sure are a better quality material.

Don
2003.5 G35 5AT Sedan, tint, XM, premium, winter, wood, & nav

 

Hey Don, glad to hear you like it. It's not quite clear though, did you mount the tweets on top of the stock tweet grills or into the door cutout under the stock grills. If there is room to mount the tweets in the door cutouts under the stock grills, that is what I'm after. I doubt losing the "swivel mount" bracket is that big a deal. I can live without it if the tweets fit under the grills without it. So if you mounted them under, was it a direct bolt-in without the bracket or did you have to silicone them in? Also, looks like you have the premium pkg on your sedan. Do you have the Bose or Base audio? I understand there is a difference in mounting hole patterns between the Panny and Bose drivers. Thanks.

 

I removed the door panels and tweeter panels as per previous threads/posts. I removed the crappy bose tweeters and pulled the Polk tweeters out of the box. I then used this plyable 2 sided sticky black electrical tape looking adhesive (tape) I buy for a lot of projects (at Advance, etc). I ran it around the rim inside the infiniti tweeter grill. Pressed the new tweeter into place. Stuck real good. I added some 3M 2 sided molding tape to double secure it. Ran the wires down like other installs and put the infiniti grill back into place. I mounted the crossover in the same place as previous threads/posts. I installed the new 6.5's. The Polk woofer mount is smaller in diameter than the Bose, so you have to center it right and drill 4 holes. That was the most time consuming part of this whole process.

After listening to the new speakers all day driving. The highs are brighter. I now have the treble setting at 3, where it used to be at 5. At 3 I have more highes than I've ever had in this car. The bass is tighter sounding. I used to have it at -1, I now run it at 0 and it sounds better over all. I purchased my DB6500's at Circuit City for 169.00, complete set.

 

Just in case I still wasn't clear. All speakers look stock. You can not tell I even messed with anything except for the improved sound.

 

OK, gottcha. Thanks for the detail, this is the first I've read of anyone mounting directly to the BACK of the stock tweeter grills, and it adds another install option I hadn't even considered. It also explains why there is sufficient clearance via your install method but not enough when attaching the tweets to the cutout flange. And, thanks to other posts here, looks like us base audio guys don't have to modify the driver mounts for the Polks (another unforeseen benefit of not ordering the Bose, hehe).