F30POST
F30POST
2012-2015 BMW 3-Series and 4-Series Forum
BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
BMW 3-Series and 4-Series Forum (F30 / F32) | F30POST > Technical Forums > Navigation, iDrive, Audio, Video, Bluetooth, Phone, Cameras, Electronics > Will disabling the rear speakers mute the rear park sensors?
European Auto Source
Post Reply
 
Thread Tools Search this Thread
      09-12-2018, 09:28 PM   #1
RoundRound
Private
8
Rep
65
Posts

Drives: 2017 F30 330e M Sport
Join Date: Jun 2013
Location: Location, Location...

iTrader: (0)

Will disabling the rear speakers mute the rear park sensors?

Hello,
I'm planning to add an aftermarket hifi system to my base audio F30 330e (2017) - due to various reasons I can only amplify the front speakers -
since I'll switch the HU to HIFI mode (line level output, no EQ) I'm guessing the rear speakers will be disabled/very very quiet -
will this impact the sound volume of the rear parking sensors? Do I have to amplify the rear speakers too?
Appreciate 0
      09-12-2018, 10:29 PM   #2
Billfitz
Major General
United_States
2016
Rep
5,039
Posts

Drives: '15 328iX GT
Join Date: Jan 2015
Location: New Hampshire

iTrader: (0)

It's going to compromise the system. My hi-fi system sends the audio information to the appropriate speakers so you can hear as well as see on the screen where and how close obstacles are. I find that the audio is more important than the video when judging how close an obstacle is. I wouldn't want to be without the audio warning from the rear speakers. Besides, how is having no rear speakers an upgrade?
Appreciate 0
      09-13-2018, 02:57 AM   #3
RoundRound
Private
8
Rep
65
Posts

Drives: 2017 F30 330e M Sport
Join Date: Jun 2013
Location: Location, Location...

iTrader: (0)

Quote:
Originally Posted by Billfitz View Post
It's going to compromise the system. My hi-fi system sends the audio information to the appropriate speakers so you can hear as well as see on the screen where and how close obstacles are. I find that the audio is more important than the video when judging how close an obstacle is. I wouldn't want to be without the audio warning from the rear speakers. Besides, how is having no rear speakers an upgrade?
Thanks,
This was a technical question, where do the rear parking sensors (PDC) output their sound to? In some car there are dedicated (very small) speakers for that - in case the HU is off - I want to find out what's the case in the F30 LCI.

I'm thinking of skipping teh rear channels for now to save on amplification
Appreciate 0
      09-13-2018, 08:18 AM   #4
Billfitz
Major General
United_States
2016
Rep
5,039
Posts

Drives: '15 328iX GT
Join Date: Jan 2015
Location: New Hampshire

iTrader: (0)

Quote:
Originally Posted by RoundRound View Post
Thanks,
This was a technical question, where do the rear parking sensors (PDC) output their sound to?
They output a signal to the REM, rear electronics module. My assumption is that it then is routed to the HU, but I can't say for sure. One way or another the tones are played through the speakers, whether the radio is on or not. That tells me that the radio on/off button only affects the radio tuner, not the amplifier.

Quote:
I'm thinking of skipping teh rear channels for now to save on amplification
You only get one chance to do it right the first time.
Appreciate 1
      09-16-2018, 04:12 PM   #5
muffking
Regular user
muffking's Avatar
United Kingdom
82
Rep
704
Posts

Drives: F31 330D M-Sport Auto
Join Date: Sep 2010
Location: Lincs. UK

iTrader: (3)

Garage List
I've done this to mine.
The H/U rear output carries the parking sensor noise. The front channels carry the subwoofer and warning dongs.

Coding the base stereo to HiFi doesn't affect this.
If you're not amping the rear channels then my advise is to keep the rear feeds as they are.
__________________
Appreciate 0
      09-16-2018, 06:46 PM   #6
RoundRound
Private
8
Rep
65
Posts

Drives: 2017 F30 330e M Sport
Join Date: Jun 2013
Location: Location, Location...

iTrader: (0)

Quote:
Originally Posted by muffking View Post
I've done this to mine.
The H/U rear output carries the parking sensor noise. The front channels carry the subwoofer and warning dongs.

Coding the base stereo to HiFi doesn't affect this.
If you're not amping the rear channels then my advise is to keep the rear feeds as they are.
Can you please clarify?
If I leave the rear channels as they are (connected to the HU) but change the coding to HIFI it would low level (2V?) signal to the speakers, will taht be enough to make them 'sound the parking sensors'?

Thank you!
Appreciate 0
      09-17-2018, 02:29 AM   #7
muffking
Regular user
muffking's Avatar
United Kingdom
82
Rep
704
Posts

Drives: F31 330D M-Sport Auto
Join Date: Sep 2010
Location: Lincs. UK

iTrader: (3)

Garage List
In short, yes.
All you're doing by coding the base stereo to HiFi is levelling out the EQ, so you're effectively sending more bass to the rear speakers. The volume and power to the speakers won't change.
__________________
Appreciate 0
      09-20-2018, 06:35 PM   #8
Encanto
Captain
Encanto's Avatar
333
Rep
884
Posts

Drives: 2018 M3
Join Date: Nov 2015
Location: Florida

iTrader: (1)

Quote:
Originally Posted by muffking View Post
In short, yes.
All you're doing by coding the base stereo to HiFi is levelling out the EQ, so you're effectively sending more bass to the rear speakers. The volume and power to the speakers won't change.
HiFi outputs are low (line) level. Volume will drop considerably compared with the Stereo high (amp) level.
Appreciate 0
      09-21-2018, 01:53 AM   #9
muffking
Regular user
muffking's Avatar
United Kingdom
82
Rep
704
Posts

Drives: F31 330D M-Sport Auto
Join Date: Sep 2010
Location: Lincs. UK

iTrader: (3)

Garage List
Quote:
Originally Posted by Encanto View Post
HiFi outputs are low (line) level. Volume will drop considerably compared with the Stereo high (amp) level.
Not when I coded mine from Base to HiFi it didn't.
After coding I had normal high level audio going to the speakers which I then fed via an amp to my speakers. Sound is much improved.
__________________
Appreciate 0
      09-21-2018, 09:06 AM   #10
Encanto
Captain
Encanto's Avatar
333
Rep
884
Posts

Drives: 2018 M3
Join Date: Nov 2015
Location: Florida

iTrader: (1)

Quote:
Originally Posted by muffking View Post
Not when I coded mine from Base to HiFi it didn't.
After coding I had normal high level audio going to the speakers which I then fed via an amp to my speakers. Sound is much improved.
Compare output levels with a multimeter. This is not an opinion.
Appreciate 0
      09-25-2018, 01:33 AM   #11
soundwave
Enlisted Member
Finland
2
Rep
32
Posts

Drives: BMW 320d 2014
Join Date: Jul 2015
Location: Helsinki

iTrader: (0)

Yes, this happened to me. Had to rewire them back and after DSP the result is much better than just the front speakers.
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT -4. The time now is 07:15 PM.




f30post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST