Back in 2008 I upgraded my old E90 M3 with the Enhanced Premium Audio System several times until I simply ended up decoding the EPS completely out of the car and coding it to HiFi: http://www.m3post.com/forums/showthread.php?t=183025
Therefore for my new 2012 E92 M3 I decided to avoid all that -and save $1900- and just upgrade from the standard HiFi, which it is a much, much better platform for upgrades than the EPS. However, I found out to my pleasure that the EPS OEM speakers -except the underseat woofers- are excellent when powered by aftermarket amps.
So in between selling the E90 and getting the E92 I collected from different sources the whole EPS OEM 4" mids, tweeters and coaxial speakers, harnesses and crossovers. Then I kept the amps, processor and underseat woofers from the E90 and transferred all those audio parts to the E92.
- EPS OEM 4" component set with dedicated OEM crossover network = front
- EPS OEM 4" coaxial = center
- EPS OEM 4" coaxial = rear side
- EPS OEM 4" component set = rear deck
- Kicker SSMB8 8" midbass = underseat
- Musicar 12" ID12 subwoofer with custom enclosure
- Alpine PDX-5 amplifier
- Alpine PDX 4.150 amplifier
- JBL MS-8 processor
The result was just fantastic...
Stock trunk space:
Custom PDX rack made in plastic:
Front OEM EPS component set in custom painted piano black speaker grill:
Rear side OEM coaxial speaker:
SSMB8 with JTsherri custom spacer:
Rear deck panel replaced with the EPS rear panel with OEM speaker mounts and piano black grills:
Inserted the added center channel wires into the OEM amp connector with OEM pins so all the wiring is centralized:
- this system is 100% reversible back to stock: all connections are done with OEM connectors/pins and the custom HiFi harness. The PDX amps can be unplugged from the OEM amp connector, and the OEM amp replugged and the sound system will sound better than stock -courtesy of the new speakers.
Idea: The E70 X5 uses the exact same HiFi OEM amp connector as the E9x. The difference is that the E70 HiFi OEM amp has 7-channel outputs (center channel) and the E9x has only 6-channel output (no center channel). If an E70 OEM amp is plugged in my system then the center channel will also sound as the center channel pins were inserted in the E70 center channel pin slots. And most probably it will sound quite decent with it and these speakers.
- the rear side and rear deck speakers were connected in parallel as the MS-8 has only 8-outputs. The EPS 4" speakers are 4ohms so the rear channels are 2ohms on each side after connection; the PDX amps are stable at 2ohms and provide the same power regardless or 4- or 2-ohms loads so this was not a problem.
A custom OEM harness was built and plugged in between the rear right and rear left speakers.
- the MS-8 is setup as follows:
- skip input setup (only required if the inputs are not full range and/or heavily EQ)
- Sub = one sub, 20Hz @ 24dB slope subsonic, 80Hz at 12dB low pass
- Front = 2-way, 200Hz @ 6dB slope Hi/Lo high pass
- Center = 1-way, 200Hz @ 24dB slope high pass
- Rear Side = 1-way, 200Hz @ 24dB slope high pass
- Calibration = -50dB
- the PDC beeps were kept by using "Y" RCA adapters and "summing" the font and the rear HiFi OEM outputs into CH1 and CH2 MS-8 inputs. The PDC beeps now are heard thru all speakers and are not intrusive -the volume still can be adjusted via iDrive.
- there is the dreaded Bluetooth echo, as the calibration is really low in volume. This is a tradeoff that so far have not crossed the unacceptable line.
In the E90 I calibrated at -35dB and somehow the BT echo was subdued enough to be imperceptible in most of the conversations. But in the E92 only -50dB seems to sound perfect, with great Stereo separation, extremelly focused frontstage and fantastic sub bass. And most important, all the sources -Pandora, iPod, Sat radio, USB, Web Radio, HD radio and regular radio- sound great regardless.
This was something that took several calibrations to get it right, as it seems that little external sounds while calibrating really change the final result. The best and last calibration was done at about midnight, just for the silence. Seriously.
- the ID12 and VP Electricity enclosure is outstanding- when the calibration is done right. This is not your typical boombox that rattles everything and at the end makes your audio irrelevant. This is some serious, SQ, sub bass impact that fills the car without overwhelming the other 16 speakers. The best part is that the level can be adjusted thru the MS-8 without messing with the amp gains. Which by the way both PDX amps output channel gains are all at minimum with the exception of the underseat woofers -more below.
- the mid bass issue of the MS-8 (or the lack thereof if a sub is part of the calibration) was solved in this particular system by using a combination of amplifier gain and the MS-8 31-band EQ. The PDX 4.150 amp woofer gains were set at nominal (exactly at the middle point) and the 100Hz ->250Hz bands were boosted accordingly to bring the midbass to par with the sub impact. The result is simply no holes in the frequency band. Both the ID12 and the SSMB8 hit solidly and deep; no plops, no clipping all the way to headache-inducing volume.
The result of all this is a system that simply leaps the EPS is all critical areas of audio: bass impact, frontstage, voices clarity, and overall audio quality and tuning capabilities -even for the rear passengers.