Enhanced Premium Sound upgrade

[Technic]

My main complaint of the Enhanced Premium Sound system is that somehow the voices sound "muddy"/"muffled". Adjusting the iDrive EQ helps some, but only 7 bands just can't make it for me.

Therefore, as it seems that in the USA the iDrive CCC cannot be re-programmed from digital to analog outputs (as it can be done in Europe) I have to use the OEM amp converted/processed/EQ/amplified output signals and then re-processed them into what I wanted to sound. The worst source to be used but that's what it is for now.

So the idea was to normalize (flatten) and remove as much as possible the overprocessing of the output response of the EPS OEM amp and then apply my own EQ curve to taste. It will be required to perform several analog/digital conversions to accomplish this, not a perfect solution but the only one that can deal with what I wanted.

The equipment installed:

- JL Audio Cleansweep DSP
- Jl Audio Summing Device
- AudioControl DQXS Processor
- Alpine PDX 4.100 amp
- Alpine PDX 4.150 amp
- Earthquake SWS-8 (replacing the 7 ohms OEM subs)
- CDT Audio CS-256
- 4" component and coaxial (4 ohms) speakers retained.

The Summing device takes the OEM front/rear/underseat woofers outputs and create a full range, 4 channel output by "summing" the individual inputs; the OEM fader functionality is thus retained. That full range output is in turn input to the Cleansweep to perform the normalization/de-processing.

The DQXS takes this "new" flat signal and process it into 8 separate channels/zones (front high pass, front lowpass, rear, subwoofer) and provide 130 EQ bands, 6 parametric EQ and 3 crossovers for an overload of personal adjustment.

To keep the center speaker relevant, a CS 256 CenterStage crossover module was installed to complement the front stage in a parallel connection. It can be adjusted for different crossover points and attenuation. In my case, it was adjusted for 400Hz (high pass) at -7db relative to the front speakers.

This new signal is amplified by two PDX amps, a 4.100 supplying 100W RMS per channel for the front/center (3) and rear (4) OEM speakers, and a 4.150 with 150W RMS per channel for the SWS-8 and 300W RMS for a yet-not-decided trunk sub.

Custom harnesses were used (RCA and speaker wires) with Molex connectors, all soldered (not crimped). Main power 4 gauge cable for the whole system was done at the OEM distribution block on top of the battery, with the OEM connector and housing soldered as well. Ground connection was made at the OEM ground point at the top of the left fender.

The whole system was designed as plugged in as possible, so the original system can be returned to stock by just unplugging connectors/unbolting.















The result of all this installation is a crisp, deep, totally transformed sound system. Now the voices -regardless of the source- are "alive", clear, sharp. The Cleansweep/summing device surprised me, both in how easy the set up was and its output. It really does work for this particular use, and as a bonus the OEM control of the volume can be retained with no penalty in noise by setting the Cleansweep main volume to 75%.

The SWS-8 in the OEM enclosures sound like my old E46 M3 JL Audio Stealthbox, due to the amout of adjustment (output level, EQ, crossover) that I can perform; IMO, the use of a trunk mounted sub is suddenly not that necessary. The OEM 4" component/coaxial speakers are the equivalent of any high end aftermarket sets in sound quality once they are also adjusted with the DQXS. Definitely they are made to play increasingly better at higher volume.

The SWS-8s are crossover'd from 36Hz to 250Hz, and the 4" are 250Hz and up.

The only issue so far is a noisy PDX 4.100, which produces a pretty maddening subtle hiss at the tweeters without any inputs. If the 4.150 amp is used instead it does not produce any hiss at all. Otherwise, there is no alternator whine, no turn on pops (there is no dedicated OEM remote turn on wire in the EPS, it is done thru the fiber optic traffic), no strange noises.

Overall, I'm extremely happy with this set up...

[808MGuy]

That's pretty awesome. I'd like to see more pics too. Especially the mounting of the amps.

One interesting thing about the SWS8 subs. I've been looking into many options as far as shallow 8" subs to see if I could find anything better. Well, it seems like there aren't too many subs that will fit in the OEM enclosure other than the SWS8s. I decided to use a computer modeling program to model outputs of the SWS8, Pioneer 8" shallow subs, an Alto Mobile Falstaff 8 and even a Morel home audio 8" (MW267). Considering that the SWS8 was among the cheapest of the subs (the Alto Mobile was the most expensive at $500+ per woofer) I was shocked at the results. I modeled two enclosures. One small sealed enclosure with about 0.35 cu ft of airspace and I also modeled a free air application. Now I expected the Alto Mobile to be the best given its price and it was but I was shocked to see that the SWS8 was nearly as flat as the Alto Mobile in its response curve. It was also a surprise that the Pioneer was the worst by far. It had a huge peak at 80 Hz and rapid drop off in response below that. So it seems like unless you want to squeeze every last bit of SQ out of your sub, the SWS8 is the way to go for both SQ and ease of installation.

[808MGuy]

If anyone is interested, here's the simulations I ran. I know the yellow text in the legend is hard to read but that is the Pioneer 8" sub. The 1st graph is the free air driver response and the second graph is a small sealed box model with the effect of cabin gain taken into account. The cabin gain used is a generic car cabin gain and not specifically the M3s cabin acoustics.

[Technic]

Sorry guys, no photos of the amp base as I stupidly deleted them.

The base is a 0.5 MDF 14" x 8.5" plank bolted to the OEM amp rack with metal strips (bent into form). The CS-256 CenterStage module is installed to the left (towards the rear of the car) of the two PDX amps.

[Sedan_Clan]

Great write up! Subscribed!

[d_dot]

Originally Posted by Sedan_Clan

Great write up! Subscribed!

+1
now im just waiting for that detailed DIY!!! Also do you still control everything thru the idrive knob and screen?

[Technic]

Originally Posted by d_dot

+1
now im just waiting for that detailed DIY!!! Also do you still control everything thru the idrive knob and screen?

Unfortunately there is no "detailed" DIY, as this installation is actually based in several existing DIYs in this forum. For example:

Premium/Logic7 OEM amp pin assignments for Molex connectors set up:

http://www.fdebrus.be/car/logic7.jpg

http://www.e90post.com/forums/showpo...8&postcount=27

SWS-8 installation:

http://www.e90post.com/forums/showthread.php?t=163804

My installation diagram (numbers are the OEM amp pins):

[808MGuy]

I finally took delivery of my 09 E90 today and when I looked in the area where you have the amps mounted, mine doesn't have that huge space available. The cover on top is much closer to the trunk floor. There's maybe a little more than an inch rise in the panel. Looks like I'll need to look deeper into this to see where amps can be mounted.

[Technic]

Originally Posted by HIS4

I finally took delivery of my 09 E90 today and when I looked in the area where you have the amps mounted, mine doesn't have that huge space available. The cover on top is much closer to the trunk floor. There's maybe a little more than an inch rise in the panel. Looks like I'll need to look deeper into this to see where amps can be mounted.

Congratulations for your M3...

That trunk trim is for the CD Changer/HD Radio; my M3 also did not have it as yours so I bought that OEM trim (some $70) for this upgrade.

[808MGuy]

Originally Posted by Technic

Congratulations for your M3...

That trunk trim is for the CD Changer/HD Radio; my M3 also did not have it as yours so I bought that OEM trim (some $70) for this upgrade.

Good to know. I already have HD radio since it's part of the premium package for 09 but I don't have a CD changer. I guess I'll look into that when the time comes.

[Technic]

Originally Posted by HIS4

Good to know. I already have HD radio since it's part of the premium package for 09 but I don't have a CD changer. I guess I'll look into that when the time comes.

It is P/N 51477070549...

[Bye Bye GTI]

did the sws8's hit the carpet under the seat once you put an amp on them?

[Technic]

Originally Posted by trebat

did the sws8's hit the carpet under the seat once you put an amp on them?

No that I can notice... the OEM enclosure "ribs" are cut so the SWS-8 are installed without any gasket as other installations with carpet problems. So they are as low in the enclosure as the OEM woofers.

[808MGuy]

Technic,

How are your SWS-8s doing with the 150W input. Does it seem like it could handle more or are you already near the limit of over-excursion. I know the RMS rating for the SWS-8 is only 150W and using it in a free-air application reduces that number a little so I'm just curious how much can they really take. Right now it seems like the jump from 150W would be either to 250W or even 375W depending on the amp I decide on but if that's already pushing it to over-excursion then a 5ch one amp solution with the PDX might be the answer.

[Technic]

Originally Posted by HIS4

Technic,

How are your SWS-8s doing with the 150W input. Does it seem like it could handle more or are you already near the limit of over-excursion. I know the RMS rating for the SWS-8 is only 150W and using it in a free-air application reduces that number a little so I'm just curious how much can they really take. Right now it seems like the jump from 150W would be either to 250W or even 375W depending on the amp I decide on but if that's already pushing it to over-excursion then a 5ch one amp solution with the PDX might be the answer.

I used them once in a sealed enclosure with 200W RMS without any issue. However, they will start complaining at any power rating if you use an EQ and increase the level of the frequencies below 60Hz. Even increasing the bass adjustment from the OEM HU can make a difference.

So level adjustment is as important as max power rating in this particular case.

[Technic]

After some tests I'm pretty sure that this subtle hiss that I mentioned before is coming from some OEM module of the car when it is on, as the other PDX amp (4.150) that I have is also showing some hiss after re-testing.

It seems to me now that when I tested the 4.150 that module was off (the car was off), so it made me think -incorrectly now- that I have a bad 4.100. But additional tests with different scenarios showed that regardless of the amp there is a very subtle hiss and even some times a faint whine that goes on and off at different times, like there is something else turning on and off even when the car is not running. None of these noises vary with engine speed or they increase with volume, so alternator or fuel pump interferrence is out of the picture. All this testing is done without any inputs to any of the amps...

There are still a couple of things that I can do to try to further minimize the hiss to acceptable levels, with better cables, shorter grounds and speaker wires, and better layout of all the components. I will not be able to completely eliminate the hiss as I'm using the Cleansweep remote volume at 75%, so I can use the OEM volume controls but that's acceptable for me.

[Technic]

Amp base:


Remote turn on is pin 13 (tuner antenna amplfier turn on, black wire) at the main CCC connector; to access just remove trim piece with trim tool and then 4 Phillips screws:

[808MGuy]

Can you crank up the input/output gains on the DQXS so you can minimize the gain on the PDX amps? That might help minimize the hiss.

[Technic]

Originally Posted by HIS4

Can you crank up the input/output gains on the DQXS so you can minimize the gain on the PDX amps? That might help minimize the hiss.

The issue is beyond that... the hiss is there without any PDX inputs and at the absolute minimum gain. The last thing that I have not tried yet is moving the main 12v line from the OEM distribution to the positive terminal straight.

The main reason that I have to go with the OEM remote turn on instead of using the Cleansweep signal sensing mode was that I was also noticing some faint whine at just start up, then 3-5 seconds later was gone. Coincidentally those 3-5 seconds were the time that the signal sensing took to turn the whole system on and audio start playing after sensing the OEM outputs.

I did not notice that whine when I wrote my initial post because I was not using the signal sensing mode, I was using the ignition sensing mode with the OEM CD Changer 12V line as the trigger. That OEM line turns on and off almost like an ignition line, however the turn off time is very irregular and sometimes it took more than an hour to really turn off and the amps were getting very hot by being on for so long. So I started using the signal sensing mode to avoid this issue... and then the whine appeared.

By removing that signal sensing feature (flipping a switch) and making the Cleansweep turn everything on with OEM antenna switching signal (pin 13) in the ignition sensing mode all the aftermarket equipment is turned on immediately at the same time my iDrive is booting up, and the whine is gone. Now the system turns on and off exactly like factory and no more heat issues...

That also tells me that the aftermarket equipment has some noise suppressor circuits indeed, and most probably the hiss is induced to the 12V line in that OEM distribution block slot by whatever OEM devices are plugged in beside it.

[eagletangogreen]

Nice write up! Thanks for taking the time to share this

[ideliver]

Techinc...wow...you have once again set the standard..

[Technic]

Originally Posted by ideliver

Techinc...wow...you have once again set the standard..

Thanks... but the "standard" should not have any hiss.