Hifi Audio upgrade project
I have owned my 2012 640d MSport Coupe for 3 months now... and from day one I was disappointing with the "BMW 676 Hifi" sound system. I previously owned a 2004 545i with Logic7 and my wife drives a 2008 X5 4.8i, also with Logic 7. I'd have been happy with a system that matched either of those... but the system fell well short.
I decided I needed to upgrade (I plan to own this car for 5 years, and want to enjoy it to the fullest extent possible). After weeks of research I decided upon a course of action - with the following goals in mind:
Because I wanted to keep the vehicle looking 100% stock and did't want cut into any of the vehicle's wiring, I purchased a custom harness that will allow me to unplug the factory amp and replace it with new amp(s) without cutting into the vehicle's wiring. The 2 options were:
I went with the Technics option - he's been active on the forums for years and the harness gets lots of great reviews. I'm glad I went this route - it really made the install much easier!
The harness allows me to:
The components I have purchased (and mostly installed):
1 x Rainbow IL-C4.2 F (part 231247) - pair of mids & tweeters for the front doors
2 x Earthquake Sound SWS-8X 8-inch (2 Ohm) Shallow Woofer System - under each of the front seats
2 x Earthquake Sound R8SWS Installation Ring Adapter for Speakers
2 x Kicker 12CX3001 CX-Series Monoblock Power Amplifier - [email protected] Ohm;, [email protected] Ohm;
1 x 4 channel Alpine MRV-F300 - 50Wrmsx4 @4 Ohm;, 75Wrmsx4 @2 Ohm;
I routed the Left and Right balanced differential signals to each of the Kicker amps, and took the line level outputs from the Kicker amps to the Alpine. The Kickers each drive a SWS-8X underseat sub and the Alpine will drive the Rainbow IL-C4.2 F's in the front doors, as well as whatever speakers I put into the rear (window shelf and/or sides).
I completed the install this weekend and there's a dramatic improvement in quality and power. I have dropped from the oem 7 channels to 6, so have sacrificed the the front centre speaker, but the telephony and navigation still work fine. The reason I went with the Kicker amps is simply because they're relatively inexpensive, compact, have good reviews, and accept the balanced differential signal generated by the BMW 676 Hifi headunit. I could have purchased just one Kicker amp, and used it to drive the 2x 2 Ohm; subs in series, but then I'd only have access to 2 channels from the head unit instead of 4 (which would effectively mean the fader wouldn't work anymore). It seems that I could either use Rainbow IL-C4.2 (2 way) or the Rainbow IL-X4 F (co-axial) speakers in the rear - or just leave the rear's OEM for now (I'm still undecided).
Below are some photos - I hope it'll inspire / help one of you guys. I didn't take photos of the underseat subwoofer installation process because it's pretty similar to the process for other BMW models (which is well documented online) - it involves removing a couple of bolts, folding the seat and the leaning it back. I didn't need to remove the plastic sub enclosures, but do recommend the installation ring adapters - they form a tights seal with the subs which I've read is critical.
The original (feeble) 7 channel "Hifi 676" OEM amp:
Here's the space once the OEM amp and bracket are removed (the harness I purchased from Technics is in the foreground - well worth it - makes the install plug 'n play). I did need to make 3 "non-reversable" changes to maximise the space available - I cut off 3 of the protruding bolts that are used to fix the OEM amp bracket in place.
The three amps that need to fit in that tiny space...
The 2 Kicker Monoblocs are really tight squeeze (they're mounted on a thin board, with foam rubber underneath). I had to solder custom 90 degree RCA plugs... straight plugs wouldn't fit. I was a little concerned about heat build up, but the gain on both of the Kickers is turned all the way down (the underseat subs are rated at "only" 150W peak), and they're very efficient class D amps - so far, no issues.
Everything (miraculously) fits:
All back together... and it all works!
Last edited by EuphoricGrIn; 06-29-2016 at 03:41 PM. Reason: Pics not visible to all fixed (I hope!)
|See More Related BMW Stories|
|Today's Posts Search|