# 2004 BMW e46 M3 SQ install



## ultimatemj (Jan 15, 2009)

Hello all,

I’m fairly new to DIYMA and it has been 20years since my last install. The time has come to return quality sound into my life!

*History*
My first system was in 1983 with a Sherwood HU, Blaupunkt amps and Alpine speakers…in a 1971 Toyota Corona MrkII :wacky: I’ll spare you the progression of vehicles and systems since, but my last install was a 91 Toyota 4Runner with 2v SonyHU, unilink 10disc changer, Alpine 3555, MTX4320, Polk MM3065s (nice tweeters) in the kicks and a JL microbox with a pair of 8s. 

The problem wasn’t the sound, but the vehicle. Great for 4wheelin, mountain biking, and camping…but not so much for a concrete jungle(moved to Chicago after building her out) commute…kinda like driving an empty school bus. :shame:

To improve the time spent commuting (hour each way), I sold the 4Runner and bought a 2004 BMW M3 






​
The M came with the CD53 Business HU and Harman Kardon “sound system”. While surprisingly good image and reasonably clean sound, it simply does not provide the type of “dynamic sound” that you can connect with. 

I’ve never been a thumper (trunk rattle-bzzt) fan, but do enjoy all kinds of music (blues, jazz, punk, rock, reggae, alternative, etc) full and “studio like”. 

*Mission:*
•	Achieve SQ that stimulates emotional response (improving my quality of life on my daily commute) 
•	Minimize weight gain (At 3400lbs & ~10lb/hp the M noticeably decreases in spirit with additional weight)
•	Maintain as much of the minimal trunk space as possible
•	Retain the factory head unit; keeping all of the factory steering wheel controls and a clean dash cluster.
•	Stealth (maintain the simple but elegant appearance of the M….and yet similar bravado).​

*System approach:*
Start with stock locations and try to stay 2-way front stage. Re-use head unit (respectable 5v balanced differential output) and old MTX amps (made in USA & >110db s/n ratio. 4320 is 75x4 or 280wx2(bridged) and 4200x is 40x4 or 200wx2(bridged)). Small coupe cabin might need signal processing, in particular with trying to keep the stock locations (13” PLDs). 

For midrange, use a wider bandwidth driver paper coned to put as much of the vocals in 1 driver, the one with the best PLDs. Use largest “drop in” IB subs that will fit without to much metal work and minimize trunk encroachment...8s.

Reading various installs and experiences shared here and on other forums, I decided to find out first hand if the HAT drivers are all they are hyped up to be. 

Based on prior e46 threads and then some tinkering with my door panels I came to the conclusion that the L6 series would not fit without breaking the stealth mission. Looking at the HAT Clarus C6s, their numbers, charts and reviews are impressive (strong and clean up to 5k!), so I'll give them a shot. 





​
Having had prior positive experiences with “high end tweeters”, I decided to pay for the (big) up charge from the Clarus tweeters to the HAT L1proR2 ring radiators. Their off-axis abilities should help out with the stock door locations. And if I need to drop the x-over up front, their size can handle it lower.





​
For the subs, I posted a question about 8" IB SQ choices and then after reading responses and a bunch of speaker specs I choose Image Dynamic ID8d2s.

Having selected drivers, the next decision was making a plan for the signal and amplification. The MTX amps in my closet have plenty of power, but little “tuneability” and can’t accept the balanced differential signal. And I can’t find a reasonable combination that keeps me from having to do passive front x-overs (4200x 200wx2 for the fronts and 4320 280x2 for the subs seems the best). This presents likely attenuation and phase challenges between the mid(90.4db 2.83v/1m) and tweeter([email protected]/1m equivalent to 94.5db 2.83v/1m).

While I was struggling with how to make this work I came across a classified for a Zapco DC650.6 

Nice…it accepts balance differential input and has super flexible digital signal manipulation. Maybe it would simplify this install to a single amp (4x50 & 2x100)? 

Well, I bought the amp and am stoked about its abilities (thanks to Complacent_One for an uncomplicated deal and merch as advertised!), but I got more than 1 credible source (Scott B, Bing, etc – thanks guys!) suggesting that 50w would not be enough for a dynamic front stage with the C6 mids. 

So here’s what I’ve got for a *System plan:
*




​*Source:* BMW Business CD headunit (CD-53)
*Signal:* Zapco Symbilink & Navone NE-744V (LOC)
*EQ:* Zapco DPN
*X-over: *Zapco DPN & MTX (sub)
*Amplification: *Zapco DC650.6 & MTX 4320
*Front Stage:* 2-wayHybrid Audio L1pro r2 – Zapco DC650.6 ch5&6 (2x100w)
Clarus C6 - Zapco DC650.6 ch½ & ch¾ (2x180w)​*Sub bass:* Pair of 8” subsImage Dynamics ID8d2 -MTX 4320 ch½ & ch¾ (2x280w)​

*Plan/Action steps:*
1)	Front stage
Baffles
Amp
Wiring​2)	Subs 
Baffles
Amp
Wiring​3)	Finish work
4)	Tuning​*Install to follow*:rockon:


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## Notloudenuf (Sep 14, 2008)

So far so good, subscribing.


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## dummptyhummpty (Feb 4, 2006)

I've got similar goals for my M3 (mainly weight and space) and I'm interested to see how this goes. Are you planing to install the subs in the factory location?


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## ultimatemj (Jan 15, 2009)

1) Front stage - Baffles

My M being an 04 there is a bunch of helpful installs already documented. So a quick shout out to a couple that I found particularly helpful

RSL (e46fanatic) Starting my first install
Meanmachine - bmw-e46-cd-focal
jvr826 (e46fanatic) Midbass issue - "tunnel effect" 
jvr826 (e46fanatic) Midbass issue - "tunnel effect" FIXED​First step was checking out the space that C6s will need to fit into…and verify that the L6s would or would not fit. Here is the C6 fitted in the door card. 










I had to shave a bunch of material off (with a chisel). This speaker (165mm) is the max diameter that will fit “down in” the card. I’m going to angle the driver up a bit and the plastic bracket opens up on an angle as well so there just might be enough room for the 181mm L6. Let’s see!


















Hmm, not looking good.
The template for the base of the baffle (used in the threads I linked) maximizes the opening and provides for solid mounting, so I began by making a pair.










Now looking at the 181mm diameter against the template I find that the angle required to fit the 181mm is simply not going to work without modifying the door card beyond a stealth/stock appearance. So as much as the L6SEs were calling my name, it is time to move on with the C6s.

















After reading the jvr826 threads, I decided I wanted to build the baffles with a negative cone shape to assist “the breathing” of the drivers. Additionally, due the depth of the drivers (76mm), and having seen some of the other installs saying 70mm was “max”.
Squeezing these in between the door card and the window rail mounting bolt means a baffle of about 2-1/4” total thickness. And The baffle template dictates how much taper I can fit, so I started with blanks 6-3/4” square by 1-1/2 thk. 









After laying out center, thicknesses and the taper, I cut cut them on the band saw.








To smooth the cut I sanded them on a wide belt before routing.









Seems I missed the pics of the router set up. Key was using the tapered waste as a sacrificial guide. I attached the cutoff with screws in the mounting ring area and then routed inner and outer diameters. Then I switched a basic straight bit out for a cabinet panel bit (to provide the inside and outside tapers. Note: This required flipping the ring and routing both sides.
Hmm, I’m missing the glue up pic as well. The only notable thing fro the glue up is putting the door panel on with the baffles taped inside to line them up. Once located and glued, I routed the assembly for inner taper.









Not sure why the first pic is large and the others are small with attachment links at the end?


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## ultimatemj (Jan 15, 2009)

1) Front stage - baffles (continued)

Here is the view of a test fit from the backside








Time to prep the doors!
First remove the door card and cut the holes (no turning back now)!















Removing the black glue connecting the foam panel to the door was a serious hassle! If there is trick to it, I don’t know it…and my hands were seriously sore from wrestling it off. Not to mention stained. My wife gave me the “eww, what’s up with your hands”. But I got ever dang last bit of it off!








Time to deaden the door~
Thinking about minimizing the weight gain I decided to try the Dynamat “Superlight”.









I covered the big opening in the door with some press board and sefl tapping screws.







I removed the airbag and electronics box, applied the deadener and the reattached.








Placed the factory foam back over the top.








Time to see if the drivers fit!


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## Mless5 (Aug 21, 2006)

Watch out for Navone, my buddy had issues with his: David Navone NE-774V LOC kills the bass - CarAudioForum.com


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## ultimatemj (Jan 15, 2009)

1) Front stage - baffles (continued)

Time to see if the drivers fit!

















Time to see if the drivers clear the window rail!










Whoa, these are a seriously tight. I had to remove the rubber magnet ring to make them fit!
Painted the baffles black. You can’t see the tab (@10oclock) that is under the dynamat. These things are solid.










You can see I still needed to enlarge the hole to benefit the work put into the baffles…and I did but I missed the pic. Here is the final assembly with weather stripping foam in between the driver and baffle.









Argh, I also forgot pictures of the non-hardening clay I stuffed in the gaps on the inside. The outside is wrapped with dynamat~

So, the tweeters were WAY less work~
For those curious about what will fit, here are measurements of the stock mid















The foam ring on the back of it keeps it from vibrating on the metal of the door. 

A simple ½ plywood piece was cut(and painted) to mount the L1proR2s in the place of the stock mid.
I added a piece of dynamat to decouple the driver…and to cover the stock tweeter hole.









You can’t see the tweeter's sexy brass cones on the other side, lol. 









Depending on how well the stage images, I might have to consider sails or a-pillars…if just to show of these hot looking tweeters. 

For now, stock/stealth it is…








If I keep them here, I might have to do something about that name plate lol!

Front Stage amp is next~


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## ultimatemj (Jan 15, 2009)

@dummptyhummpty - Plan is to drop the two 8's in from the top of the rear deck, where the HK sub was...but for sure I'll have to open up the holes to make it work.

@Mless5 - Thanks for the heads up; I'll check it out~


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## rcurley55 (Jul 6, 2005)

ultimatemj said:


> @dummptyhummpty - Plan is to drop the two 8's in from the top of the rear deck, where the HK sub was...but for sure I'll have to open up the holes to make it work.
> 
> @Mless5 - Thanks for the heads up; I'll check it out~


You can get 2 8's under there without any cutting - the holes are not big enough, but it still works and is a pretty easy install.


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## ultimatemj (Jan 15, 2009)

1) Front Stage – amp location

The Zapco DC650.6 being as wide as it is and with subs going in the rear deck, that leaves me with placing it in the “wheel well”. I’d really prefer to avoid raising the floor and to not give up the factory “fix-a-flat”. Luckily the DC650.6 is narrow enough to fit between the Styrofoam support and the rear trunk wall! 








[Sorry for the crappy cell phone pics...ugh]

To mount it I traced the stock foam piece onto a ¼” piece of plywood and mounted the amp and handles to it.










It wedges into place nicely!










I still need to figure out the floor top, but I’ll push that into the “finishing” phase. That said, I have some ideas for the floor~










You can see in the amp pics the wiring…but here are the pieces being put together.

Front Stage – Wiring
For the drivers I picked up 8conductor cable from Parts Express








and 8 conductor Neutrik connectors



























I used the same Neutrik connectors for the signal. I spliced a symbilink cable and the Navone LOC into it.
















Seems I forgot to take pics cutting the factory connectors and attaching the Neutriks, but there are good pics here William - bimmer.roadfly - DIY post - Full H&K Audio Upgrade (long!) and here rcurlley55-project-m3-underway

Here is the wiring scheme I used:

Factory Amp - Black Connector
PIN 38-Yellow / Red (FL+) Neutrik 1+ Symbilink White (pin 5)
PIN 30-Brown / Orange (FL-) Neutrik 1- Symbilink Yellow (pin3)
PIN37-Yellow w/Black stripe (RL+) Neutrik 3+ 
PIN29-Brown w/Orange stripe (RL-) Neutrik 3-​
FActory Amp - Gray Connector
PIN 9-Blue / Red (FR+) Neutrik 2+ Symbilink Red (pin 6)
PIN 17-Brown / Orange (FR-) Neutrik 2- Symbilink Black (pin4)
PIN 8-Blue w/Black stripe (RR+) Neutrik 4+
PIN16-Brown w/Orange stripe (RR-) Neutrik 4-​
8 pole connector to speakers – 

Factory Amp - Black Connector
PIN 33-Tweeter Front Left +Yellow/Red Neutrik 1+ Dayton White 
PIN 34-Tweeter Front Left -Yellow/Brown	Neutrik 1- Dayton Black
PIN 23-Woofer Front Right +Blue/Red Neutrik 2+ Dayton Brown
PIN 22-Woofer Front Right -Blue/Brown Neutrik 2- Dayton Teal
​Factory Amp - Gray Connector
PIN 11-Tweeter Front Right +Blue/Black Neutrik 3+ Dayton Yellow
PIN 12-Tweeter Front Right -Blue/Brown Neutrik 3- Dayton Green
PIN 4-Woofer Front Left +Blue/White Neutrik 4+ Dayton Blue
PIN 3-Woofer Front Left -Blue/Brown Neutrik 4- Dayton Red​
Also of note, I grounded the amp in the same place as the battery. After reading this about Grounding at frame where battery grounds, I’m comfortable that I’d never have the negative disconnected from the battery, with the positive still connected, and try to crank the car.

*Subs next!*


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## jab4au (May 31, 2010)

I'm liking this...... From install to choice of equipment. Well done!


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## BigBadBakken (Feb 16, 2010)

Looks great! subscribed!


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## slvrtsunami (Apr 18, 2008)

Love the wine accents!! great work so far. Nice detail.


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## Audioguy36 (Jun 10, 2010)

Damn nice install!


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## sydmonster (Oct 5, 2009)

indeed some great work here... nice car to nice gear.


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## beyondredline9k (Nov 28, 2010)

Great Work


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## ultimatemj (Jan 15, 2009)

A bit of Turkey day delays...and some house projects.

*Bring on the subs!*

Again, thanks to those that posted before me! Good inspiration for dropping 8’s in the deck came from these 2 installs:

12Velectronics - bimmerforums - 8s in rear deck
admranger - bimmerforum - E46 M3 Hybrid Audio Technologies L8 install (finally)​Lots of good ideas and pics here: rcurlley55-project-m3-underway

And I found a good rear deck removal explanation here:
Shuskan3-e46fanatics-***BMW E46 Coupe Rear Deck Removal DIY***
Only thing missing from that post was any kind of visual on the (frustrating) headset clips. I found that once you I had the trim removed from the leading edge I was able to pry it up enough to see and remove the clips.





​ 

I didn’t take pics of the stock deck, but here are the holes after enlargement~








Anybody know what that little sensor is to the left center? Curious~

Locating/fitting the top level of the baffle. Making sure I'm not too high, nor letting the woofer rest on the metal, and locating/spacing them.








Due to pic limits I left out routing the spacers to support the baffle and the glue up, but here is a pic showing the bottom of the finished baffles and their various support pieces. 









Well this is a crappy pic, but it shows how close the plastic rear deck support piece was to the baffles. It cleared, but not enough room for the driver surround. Also shown in this horrible pic is the non-hardening modeling clay stuffed into the gaps from the I.D. to help connect and seal.









I decided to just remove what I needed to remove from the bracket…so I could still use the stock mounting bolt…and it worked out just fine. One side notched...the other done similarly.









Can’t forget the Dynamat! A couple of layers to complete the seal and deaden the deck~







My son was helping...in his own way!

*
Subs are in!*
Top view








Rear view – Being dual voice coil, the positioning of the connections was a big part in having to make the hole bigger. The magnets cleared the stock holes, but the baskets and the connectors did not. I had to choose between bigger holes or a custom rear deck cover. The other deal killer was the holes were not positioned far enough away from the glass to allow the back edge to mount without modifying/removing the plastic that holds the stock deck topper in place (seen in the bottom of the prior pic).








Honestly, this pic doesn’t relay how little they encroach into the trunk. In fact, I think I GAINED space as compared to the stock HK sub 

Sub amp next!


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## wdemetrius1 (Aug 16, 2007)

Subscribed. Great thread.


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## bertholomey (Dec 27, 2007)

Sub'd!


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## FartinInTheTub (May 25, 2010)

I have a 2000 328i and I have been considering the same sub setup as you. I have 2 idqv3 10s like yours and am thinking about getting this started. You're running the idq subs free air... is this optimal? It seems as if you'd lose a lot doing this. I was considering enclosing them from below. any ideas?


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## ultimatemj (Jan 15, 2009)

@FITT - Regarding IB versus sealed, I guess it depends on what you are looking for. I am SQ focused and not expecting to give anything up from going IB, but I won't know until I get to tuning 

Now I am giving something up by going 8s instead of 10s. I'd expect more SPL from increased surface area, Xmax and power handling of the 10s. 

But to fit the IDQ10s, I think you'll have to choose between hiding under the stock trim/deck panel and cutting into serious sheet metal (double layers and likely into structurally significant areas). Much more basket clearance would be needed for the 10s~








Mic10s - BMW version2.1 put 4 10s in his rear deck, but he both did a custom deck and (I assume) cut a lot of metal....but maybe he lifted the baskets high enough to avoid getting too crazy with the cutting?

If I was going 10s, I would not cut further and would mount from below and give up trunk space. Then again, if I was looking for more SPL, I'd follow rcurlley55's  approach and simply add two more 8s where the stock rear speakers lived. 

But I'm just not willing to give up stealth interior, trunk space and only "safe metal modification"....or I'd mimic Mic10is install!

Good luck and show us pics of your direction!


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## FartinInTheTub (May 25, 2010)

I have another option I'm considering. The CDT Eurosport ES-06+ makes a nice dedicated subwoofer I've heard. I was thinking 2 of these in the rear deck mounted under the stock deck in small sealed enclosures mounted from below. I'm not looking for crazy bass... just smooth clean SQ bass. I would be running these with an Audison VRX 2.150. what do you think?


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## minibox (Mar 25, 2009)

nice work so far! Love the car!


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## ultimatemj (Jan 15, 2009)

Sub amp install~

So I installed the MTX4320 and found the x-over didn't adjust!
Note: the postion of the amp is so I can access the adjustments through the factory trim's CDchanger door.








I turned the pots back and forth...and no matter where I had it set vocals were being played through (guessing @ the 200Hz high end of the internal x-over's range). It was *super* distracting to the stage 

Luckily I also had a NIB 4200x sitting in the closet. And when I say NIB, I mean NIB; check out the t-shirt and the birth sheet 














Anywhose, here is what the space looks like behind the driver's side rear quarter trunk trim panel.








I'd show more, but the other builds I referenced earlier cover this extensively. I removed the factory amp, the BMWAssist module (I don't use it) and 1 of the metal bracket assemblies. 

For an amp rack, I made a plywood frame that attaches at the bottom and near the shock tower. The top of it is angled to receive a "french cleat".








This pic shows how the cleat gets secured to both the frame and a set of mounting blocks. These 2 screws secure things such that there is not any movement, but it is fairly easy to unscrew for removal.








Note: The orientation of the amp is so that the adjustment knobs are on top and the majority of the wires are on the bottom.








Note 2: There is enough room to mount another amp on the back side. I originally was going to use both MTX amps and had planned the size/location of the rack to handle them...but I stumbled across the used DC650.6 leased:

I've still got some wiring "clean up" to do, but I thought I'd go ahead and share the progress.










So, I temporarily wired the subs, just to get the quick fix of sound.

Good news is I've got bass! Plenty of low end from the 2 ID8s 

Bad news is I've learned I've got *a lot of work to do *on deadening the rear deck. Bzzt, bVrt, kzT​

*Next up - Sub wiring and rear deck fortification!*


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## sydmonster (Oct 5, 2009)

props to the real-school gear!! that MTX series were mint!

...Such a cool DIY install, yet kinda let down by lo-q photos. No harsh criticism.. just noted it.


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## ultimatemj (Jan 15, 2009)

Thanks!

I'm guessing you can't read it from my super compressed crappy phone pics, but the *A-weighted S/N on the birth sheet is 124db! *I don't recall seeing anyone claim numbers like that for their amps~

If that measurement reference is apples to apples comparable to today's amps, it might be "cleaner" than the DC650.6  Note: I don't have it's birth sheet, just the >95db spec from the manual.

That said, it is hard to know what the Navone LOC is doing to the noise floor...where as balanced differential directly tapped into the symbilink is (likely) as low as it can possibly go


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## Mirage_Man (Jun 29, 2007)

I loved those MTX amps. I had a 2150 and a 275 up until a couple years ago. 

Love the install BTW!


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## Chayse (Nov 23, 2010)

Very nice install. Looking forward to more.


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## ultimatemj (Jan 15, 2009)

Holidays have gotten in the way!

I've had no time to address the rear deck reinforcement, but I have been doing a little tuning 

I tried the C6s as low as 50 and as high as 100, but for now have settled in on 70Hz HP. 

On the high end, I tried 2k, 3k, 4k, 5k, 6k and all sounded decent. Impressed with the L1proR2s range! Right now I'm set at [email protected], as the higher x-over point seems to help separate/open the stage.

I was sensing a bit of mid-bass "muddiness" and found clarity by turning the sub x-over down to ~60Hz LP (from 80) and EQ'd a 3db cut @1k. This SERIOUSLY opened things up...mud is gone.

Through all these x-over tweeks I found that I had to keep adjusting my levels (Tweet, mid, sub) and think that I need to stop here until I get my sub playing clearly. The vibrations I'm getting on certain songs/frequencies is likely confusing my efforts. 

That said, when I turn the sub down (fade amp signal via rear output of HU) the front stage is really shaping up! *Clear, wide and about top of the dash high. *

Really happy with the HAT drivers 

Now if I can just find the time to finish the sub install! Looking like January


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## ultimatemj (Jan 15, 2009)

Long time between updates, but some progress was made 

I enjoyed the Zapco DC tuning ability so much that I have replaced the MTX sub amp...with a Zapco DC1000.4 

That led me to redo my trunk amp install altogether!





























I re-tuned the system and have a much better integration. With exception of a few resonant rattles that can draw attention rearward, the front stage now contains the large majority of the bass!

Since the IB install doesn't requires anywhere near the power a box would, I've got 2 free channels to play with


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## Derekj (Aug 11, 2011)

Some great info here! I just got a 2001 325xi wagon and want to do some stereo upgrades but really don't want to change the head unit. Looks good!


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## ultimatemj (Jan 15, 2009)

Happy to hear it might help you Derekj!

Please share your efforts with DIYMA when you start~


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## Derekj (Aug 11, 2011)

ultimatemj said:


> Happy to hear it might help you Derekj!
> 
> Please share your efforts with DIYMA when you start~


I sure will!


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## ultimatemj (Jan 15, 2009)

Long time no update!

I've had too many other projects going on to turn the system into a 4way (3way+sub), but I now have REW and a Umm6 mic and can spend some time dialing things in with the ZapcoDC processor 

Good news/bad news....Overall the levels match up with my housecurve, but my cabin dimensions with door mounted mid ranges appear to have serious modal issues in the mid range! 
All speakers playing 1/3smoothing vs HC








Sub 1/12th smoothing, Mids+tweeters ( L only, R only) 1/6th smoothing, & All 1/6th smoothing








This was taken after 4 EQ iterations, which also included trying the sub x-over moved up to 90Hz but it had NO impact on the null @70Hz...and resulted in an even bigger hump from 90 to 120 

Before I go much further, based on JohnM's recommendation (REW's author), I need to take some measurements with periodic Pink Noise to reduce the influence of uncorrelated "random" pink noise and/or need for long (30s) averaging (which I was not doing!)


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## benny z (Mar 17, 2008)

Very cool! Love seeing HAT bimmers.


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## ultimatemj (Jan 15, 2009)

Sounds to my ears like I'm making progress on the tune, but I'm clearly struggling with comb filtering and unclear if the use of high Q filters is helping or "making a mess".

Baseline (no EQ) ugliness from 200 to 600Hz was mirrored when I measured from the passenger seat (Left looked like Right from driver's seat) :worried:









The big change in my tune started by lowering my mid/tweet x-over to make use of the L1proR2s low Fs (580Hz) and to address the "hole" from the 6-1/2 beaming around 2000Hz....as well as I found flipping my tweeters 180 phase provided a better sum at the 1800x-over point. After about 6 iterations of EQ, measure, repeat, it feels like there are a ridiculous number of EQ points...
















But the resulting graph looks better and the sound is improving!









All speakers playing vs House curve shows a wicked null ~75Hz. I tried moving the x-over point up and down, changing time delay, and even adding up to +6db Q6 @75Hz and the null was unaffected  








This graph is with 80Hz x-over and no EQ on the subs.

Traveling for work this week, so I'll review to see what EQ I might be able to backout and try to come up with a strategy for 60 to 80Hz!


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