[DaveDee]

Not being all that happy with the HK system (even though it’s supposed to be good) I decided to install the Alpha 1 speakers by Bimmertech

There are a lot of rave reviews on these but mainly by installers or Youtubers

The setup was the woofer replacements and the front speaker kit (doors and centre dash)

First I have to give full marks to Bimmertech for excellent Customer service, free delivery (and it was international)
The packaging was really good but a bit over the top as it’s only good to store your old speakers and no big deal about unboxing stuff it it adds more cost

They’ve written instructions for the G42 specifically which is good to see given the age of the car

And for those dreading it the good news is the underseat woofers were not glued in

Tool set is minimal and the door cards are really easy to remove and don’t have any of the previous clips, the system is great and there are studs on the door that match plug clips on the door card

Overall the install was dead simple but allow around 3-4 hours

After doing the woofers I tested the system and was a bit disappointed as the rest of the system still sounded muddy so overall not a good sound, but after finishing the doors and front centre speakers it’s absolutely transformed the system…. not the best I’ve heard but a big upgrade for a reasonable price and the woofers come to life with the other speakers.

If you are considering doing the system it’s well worth doing the woofers/doors and front centre speakers… maybe even the back

Now to the next project
Now added the rear (6 speakers).....and that
made a big difference.
After quite some testing across various genres the stock rear speakers after the front upgrade sounded quite ordinary, especially if you code Bowers and Wilkins sound profiles in with Bimmercode.
Now the system is complete I'd highly recommend going to the full system from the get go if you are inclined to spend the money at once.
It is really good, I'd give the stock HK system (14 speaker) a 4.5/10 for sound quality and with the complete upgrade 8.5/10. Huge difference in volume and presence with bass response somehow improving again with the rear speaker set
Of note if you are ordering make sure and order the oval tweeters for the rear deck speakers, also there are no tweeters in the rear passenger side panel.
Instructions incorrectly mentioned a speaker plug socket to disconnect before removing the rear side panel, they were not fitted to mine so great care is needed taking out the rear side panel as the speaker lead is fairly short.
Installation was really simple and the instructions are quite accurate

[AlexM240i]

Thanks for your review.

So this means the speakers and subwoofer sizes of the G42 are the same than F22s !! Great news.

Could you please elaborate about the "decoupling harness" and how to remove the door panels ?

Thanks.

[DaveDee]

Originally Posted by AlexM240i

Thanks for your review.

So this means the speakers and subwoofer sizes of the G42 are the same than F22s !! Great news.

Could you please elaborate about the "decoupling harness" and how to remove the door panels ?

Thanks.

The wire harness in the new model is a single wire harness with speaker ground and an electrolytic capacitor in the + lead I believe other models have a Y lead where the input from the factory speaker goes to one end, the other to the alpha speaker and the tweeter to the remaining lead. So in this one the single lead is connected to the factory speaker input, then to the alpha speaker which now has 2 sockets. The tweeter plugs into the other socket

The door cards on our car are brilliant, there are solid steel studs on the door and plastic sockets in mounts on the door card. There are also 4 x T20 screws to remove as well as the bowden connector (door latch) and wire harness. I started using a large trim removal tool and twisted it next to the studs to pop the studs. No clips to break. I started at the bottom near the back of the door, there's a good gap to start the tool and work around from there. Like other cars the top lifts upwards to remove
The manual tells you to disconnect the battery but if you do you won't be able to slide the seats for doing the woofers, just DONT unplug the airbag connectors

The instructions from Bimmertech are written for the G42 Iv'e attached a copy of the installation manual hope it helps

[AlexM240i]

Originally Posted by DaveDee

The wire harness in the new model is a single wire harness with speaker ground and an electrolytic capacitor in the + lead I believe other models have a Y lead where the input from the factory speaker goes to one end, the other to the alpha speaker and the tweeter to the remaining lead. So in this one the single lead is connected to the factory speaker input, then to the alpha speaker which now has 2 sockets. The tweeter plugs into the other socket

The door cards on our car are brilliant, there are solid steel studs on the door and plastic sockets in mounts on the door card. There are also 4 x T20 screws to remove as well as the bowden connector (door latch) and wire harness. I started using a large trim removal tool and twisted it next to the studs to pop the studs. No clips to break. I started at the bottom near the back of the door, there's a good gap to start the tool and work around from there. Like other cars the top lifts upwards to remove
The manual tells you to disconnect the battery but if you do you won't be able to slide the seats for doing the woofers, just DONT unplug the airbag connectors

The instructions from Bimmertech are written for the G42 Iv'e attached a copy of the installation manual hope it helps

Great explanation. Thanks again buddy.