Just bought the car...Got rid of my BMW X5, which was starting to nickle and dime me to death....looking forward to not having to work on this IS for at least a couple of years.

I like it so far, except the non-ML sound system has a lot to be desired. The upper-mids and the treble from the front dash speakers are almost non-existent, even after playing with the settings.

So I pulled the front corner dash speakers to take a look at its size, and to see what I can drop in there for a quick improvement.
I do plan to add a real sub in the back to replace what's in the rear deck....

Once I got the dash speaker out, I was thrown for quite a surprise. This speaker is coaxial, and its crossover network makes no sense to me.
If you take a look at the rough schematic, I think that you would agree.

I rewired the existing speaker to 1st order Butterworth, using the existing choke and using a non-polarized 6.8uF capacitor, but it didn't sound much better. The tweeter just isn't loud enough.
I'll end up ordering a 4" speaker to replace it, but I thought I'd post the pictures and the schematic for someone who may want it in the future.

Also, does anyone have a recommendation on a good sounding dash speaker? I used a pair of Infinity REF-4022cfx on my wife's NX300h, but I wanted to stay 4 ohms on the IS, since I see threads of the amps giving out on the IS.

 

 

I ordered and installed some RFs to replace it. Here's what my speaker looked like... 2016 non-ML. Did you remove the cover or something or is that how the speakers looked as you removed them?

Stock top, aftermarket below.

It did make a decent improvement. For testing, I installed one side only, then switched speakers to front bias completely, then cycled left and right. I did this with several songs.



Link to the speakers: https://amzn.to/2O2GhNE

 

My pic was taken as it came out of the car. They must have changed the speaker for the 2018MY.

I ordered a Kenwood 4 inch to put in the dash. There's an immovable object on the driver's side dash, and wanted to use a speaker with a small magnet as to not have to mess with that.




Did that Fosgate speaker fit without hitting anything?

 

I recall my MY16 having that too. looks like a vent duct? My speakers did not hit anything, but it did require minor trimming of the RF speaker brackets (2 on each speaker) to fit perfectly. I used a pair of snips--very easy.

I verified the speakers fit my car through crutchfield recommendations. didn't feel like trial and error. though technically they required some modification but thankfully to the speaker and not the car.

 

Cool. Thanks for the info. If I don't like the Kenwoods, I can go to something with a bit bigger magnet then.

 

I'd really like to run a 2 channel setup w/ sub addition; new 2 channel amp, new wire, new front component (or 2 way to keep the cost down) speakers. Did that to my 2016 Lexus CT and it made a world of difference for little money. I've been hesitant to try that on the IS though as I read someone saying that its not possible with the way our head units process audio. I can see it being not optimal, but not impossible. I think i read our headunits have an internal crossover preventing full range from reaching the aftermarket amp... but i've been too chicken to try. Haven't bothered to research.

 

I was eye-balling the Rockford DSR1 DSP unit to correct the signals on the IS, but it appears they do not have a harness (or the firmware) for the IS with NAV.

After I install the new 4 inchers in the dash, I am going to use your DIY to add a real amp and sub in the trunk. I'm hopeful that will be enough to satisfy my ears.
I do plan on doing a fiberglass sub enclosure in the passenger corner of the trunk though. I want to keep the trunk floor uncluttered.

As a side note, it appears you and I have the same taste in cars. I am currently without a BMW in my garage, but I hope to add a E46 330 with a 6 speed manual as soon as I can find a nice one (much to my wife's disapproval) in the empty spot.
Of all the Bimmers I've owned (E36, E46, E85, E70), I miss the E46 the most.
We also just traded a 2015 CT in for my wife's NX hybrid 3 months ago.

 

Seems we do! I am also considering a hybrid NX for my next car. i just wish they included the F Sport package w/ the hybrid in the US. i hate the shark front bumper of the non-f sport. but may just go IS350 F Sport. we'll see.

As far as BMW yep I had an E46 330i 5-speed. Drives like our IS but 200 lbs lighter. I'd like an E46 m3 convertible one day as my toy car. Having it as a daily driver though would be too much of a headache keeping it up. Extremely reliable but only with meticulous upkeep.

I have to do updated pics of my sub setup. it looks way cleaner than my original pic. I relocated the amp to the trunk so all that's needed is a quick disconnect (push with finger) to remove the wire and take the box out of the trunk. i can convert to an empty trunk in less than 10 seconds.

 

YES! I always do the entire brake job with Zimmerman rotors and Akebono pads, and refresh the entire cooling system including the radiator as soon as I buy a Bimmer.

Would love to see where you hid the amp.

 

I always used Genuine BMW pads or ATE pads but that's just me =P

I hid the amp in the lower section on the left side, next to the tail lamp. There's an empty space down there. Fit perfectly. I'll see if i can get some pics later.

 

Work completed. The speaker change made quite a difference in the sound.
With the stock set-up, I had to bump the treble up like 4 notches to get just a hint of strings and cymbals.
With the replacement Kenwoods, I now have the setting at 3 notches below center, mids at even, and bass at 2 notches up.
It now sounds like it should....almost sounds like I took the wet blankets off of the stock speakers.
Now, I'm not saying that this is audiophile quality....but it is certainly much, much better than stock.
I'm sure I could have done better in regards to SQ, but for under $40 including the wiring harness, this improvement/cost ratio is hard to beat.

The speakers I chose dropped right in. The small magnet structure,and its shallow depth made the installation easy.
90dB/w/m sensitivity makes good use of what little power the amp puts out to the front channel.
I did have to trim a bit of plastic off of the dash to clear the speakers, but it was a quick 1 minute job with a dremel.

Pic of the speaker, and the GM speaker harness I was able to modify to fitting our cars. The harness thing was not my idea....I saw a post on this forum that mentioned this.

 

Very interesting

 

nice upgrade. $40 and quick less than hour install. i echo that as well my treble isn't all the way cranked up as it was with the stock speakers. this and a sub makes a world of difference. not audiophile, but a clear improvement. since our cars aren't the most mod friendly when it comes to audio. which is a shame cause that's usually one of the first mods i do to any car.

 

Just a note. Your schematic of the LPF is awkwardly drawn and incorrect. The way you drew it is a Capacitance input filter, which makes very little sense as a filter for speakers.