Menu
Home
Forums
New posts
Search forums
What's new
New posts
Latest activity
Members
Current visitors
Log in
Register
What's new
Search
Search
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Reply to thread
Click here to become an Official Member of BMW Club Malaysia
Download Form
Home
Forums
The BMW Range
3 Series
E46
[DIY] Amplifier IC upgrade
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Message
<blockquote data-quote="aidilj" data-source="post: 448672" data-attributes="member: 20536"><p>Update:</p><p></p><p>After the morning experiment it is concluded that the stock heatsink couldn't cope with the heat generated by the IC. Class AB amplifier never is an efficient amplifier. All parasitic components around the IC was removed and it sounds great until the IC heats up then sound would be distorted.</p><p></p><p>It is also concluded that impedance seen by the head unit on the speakers are 4ohm. I've removed the rear deck speaker and it has 4ohm stamped on it. The front speaker was not physically removed but from the radio connector, resistance of front and rear are the same. If the door mid range is 2ohm, probably it is connected in serial with the tweeter.</p><p></p><p>While also checking on the resistance it is found that the wiring for the front speakers are incorrect - suspected that previous owner changed to aftermarket then put back OEM head unit before selling and wireman doesn't do a great job. Explains why left/right balance setting doesn't really set the balance. Fixed.</p><p></p><p>For reference here is the pinout for my headunit, might be applicable for you too.</p><p></p><p>Cheers</p><p></p><p><img src="http://i791.photobucket.com/albums/yy197/aidilj/Amplifier%20IC%20upgrade/Old20Gen201720Pin20Radio20pinout.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p></blockquote><p></p>
[QUOTE="aidilj, post: 448672, member: 20536"] Update: After the morning experiment it is concluded that the stock heatsink couldn't cope with the heat generated by the IC. Class AB amplifier never is an efficient amplifier. All parasitic components around the IC was removed and it sounds great until the IC heats up then sound would be distorted. It is also concluded that impedance seen by the head unit on the speakers are 4ohm. I've removed the rear deck speaker and it has 4ohm stamped on it. The front speaker was not physically removed but from the radio connector, resistance of front and rear are the same. If the door mid range is 2ohm, probably it is connected in serial with the tweeter. While also checking on the resistance it is found that the wiring for the front speakers are incorrect - suspected that previous owner changed to aftermarket then put back OEM head unit before selling and wireman doesn't do a great job. Explains why left/right balance setting doesn't really set the balance. Fixed. For reference here is the pinout for my headunit, might be applicable for you too. Cheers [IMG]http://i791.photobucket.com/albums/yy197/aidilj/Amplifier%20IC%20upgrade/Old20Gen201720Pin20Radio20pinout.jpg[/IMG] [/QUOTE]
Verification
Post reply
Home
Forums
The BMW Range
3 Series
E46
[DIY] Amplifier IC upgrade
Top
Bottom
