E90Post
 


MINHS Auto Care Center
 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Technical Forums > AUDIO/VIDEO + BLUETOOTH + Electronics/Alarm/Software > Remote turn on issue when fitting aftermarket amp to OEM HU



Reply
 
Thread Tools Search this Thread
      01-30-2012, 06:10 AM   #1
bmwak
Major
bmwak's Avatar
United Kingdom
22
Rep
1,074
Posts

 
Drives: 325D M-Sport Coupe (E92 LCI)
Join Date: Sep 2008
Location: London

iTrader: (3)

Remote turn on issue when fitting aftermarket amp to OEM HU

Hi all,

I recently fitted an aftermarket amp (namely the JL Audio XD400/4) to power my boot sub and a set of components (Focals) that I will soon be fitting to my E92.

As the amp does not have signal sensing, i had to tap into a switched live (cigarette lighter). Now the front speakers and sub only kick in when the ignition is on (i.e. not when the key is just plugged in). I think I can get around this by using a signal sensing amp (which turns on when the amp reads the HU feed coming through). I like my amp so donít want to change it. However, as i am still using the OEM Professional HU, I will need to use a proper line driver (at the moment Iím only using a Directed RCA convertor).

Having had a look at Line Drivers Iíve noticed that two models, namely the Cache COE6 and Audiocontrol LC6i to have signal sensing technology. However, from what I gather they still require a switched live signal. My question is will adding one of these into the system cure the issue of having the amped speakers only kicking with the ignition on. The Directed RCA convertor works fine with no audible interference or anything Ė so I donít want to waste money on a line driver if it wonít help me fix the issue iím having.

Can anyone help on this?
Appreciate 0
      01-30-2012, 06:23 PM   #2
taibanl
Brigadier General
taibanl's Avatar
65
Rep
3,648
Posts

 
Drives: BMW
Join Date: Sep 2010
Location: NA

iTrader: (4)

See the new table of contents thread 2d post
Appreciate 0
      01-30-2012, 07:04 PM   #3
VP Electricity
Brigadier General
VP Electricity's Avatar
United_States
70
Rep
3,181
Posts

 
Drives: E91 XDrive
Join Date: Jan 2008
Location: portland oregon

iTrader: (3)

Signal sense widgets work fine in that car. PAC TR4. Solves that problem cheaply.

You don't need a line output converter. The 400/4 can take that speaker level input.

BUT... the head unit output is not linear, so you are amplifying a very nonlinear signal. If the signal coming out of your head unit were linear, this graph of the electrical output would be flat:



So you're gonna want to correct that or it doesn't matter what else you do. The Jl CleanSweep will correct it on the front channels AND do signal sensing...
__________________
Musicar Northwest - TOP 12 Retailer 2014
OE-Look Enclosures for F30/F80, F32/F82, and more!
Ask about our bolt-in audio upgrades for BMW.
Appreciate 0
      01-31-2012, 08:32 AM   #4
bmwak
Major
bmwak's Avatar
United Kingdom
22
Rep
1,074
Posts

 
Drives: 325D M-Sport Coupe (E92 LCI)
Join Date: Sep 2008
Location: London

iTrader: (3)

Quote:
Originally Posted by VP Electricity View Post
Signal sense widgets work fine in that car. PAC TR4. Solves that problem cheaply.

You don't need a line output converter. The 400/4 can take that speaker level input.

BUT... the head unit output is not linear, so you are amplifying a very nonlinear signal. If the signal coming out of your head unit were linear, this graph of the electrical output would be flat:



So you're gonna want to correct that or it doesn't matter what else you do. The Jl CleanSweep will correct it on the front channels AND do signal sensing...
Thanks for your reply - this is very helpful info!

I have been looking at buying a DSP unit and was looking at the MS-8 but thinking of adding it a bit later as it is a bit over my budget at the moment.

The JL Audio CL441DSP Cleansweep unit seems to fit the bill, both budget-wise and provides the signal sensing function to correct the issue. Is there any major advantage on going for the JBL MS-8 (apart from the fancy screen) over the JL Audio CL441DSP?
Appreciate 0
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
Forum Jump


All times are GMT -5. The time now is 11:16 AM.




e90post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, 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