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Old 10-15-2011, 08:05 PM
Evlengr's Avatar
Evlengr Evlengr is offline
Ukemi - that's how I roll
Location: MD
Join Date: Feb 2007
Posts: 4,252
Mein Auto: 2013 Audi S4 2010 MT MCS
Audio Tidbits

A small update.

Today after three days of rain I finally had some time to do some R & D, or retro-engineering would be more proper.

I have opened the door panels so many times that I can now do it in about 15 minutes per door.

First thing I wanted to confirm myself, The basic sound system (business) fron doors has a small tweeter and 4 in driver. It is 4 ohms. It says so on the speaker and I tested it using a Fluke 77 series III Multi-meter as well as an old fashion Simpson. The back doors are just a single driver in each door.

The mid-bass drivers are 2 ohms (the ones under the seats).

I put the original speakers back in the front doors and left the Alpine's in the back doors so I could do A-B comparsions.

I used two Shure beta 58 mics and a tascam multi channel recorder. I then used Adobe Audition professional audio editing software to check the frequency response.

The abridged results are this:

The stock speakers are technically inferior to the Alpines (and probably anything after market) as I suspected.

Stock speakers can not reproduce decent highs over 14kHZ and lows below 800Hz.

They also cannot reproduce real stereo imaging dead center above the arm rest console, which should be the sweet spot. Subjectively I can hear the left channel seperate from the right channel, which is great if you listen to everything in mono, but not if you like any music that was recorded in stereo after 1962, Lol.

I left them in today to run various types of music and speech through. Wow, can't wait to get them back out. Yikes they are bad.

If you want the details I am happy to share them with you.

Also, learned some good things to remember when removing the door panels besides the obvious. Always start to remove the wood arm facia from underneath and gently work the pry towards the middle at a slow straight line up the length of the arm, that is were the clips are.


X3oiler was nice enough to take the constructive criticism to pm's but I don't mind good input and admitting there can be problems. He stated that my suggested method could cause the veneer to crack. Actually, the first install I had was done by a "Pro" and he cracked and had to replace my wood veneer.


I recommend doing the back doors first because hey if you do mess up not as many will see it.

I can also confirm that the brown striped wire is the common ground to each speaker.

Hope these little tid bits help folks.

Feel free to ask questions and add to the mix, and although I have technical data to back it up sound is subjective and if you are happy with your sound then I will do my best to keep my mouth shut unless you ask.
2013 S4 Loaded (and NO RFT's) Awesome is an understatement
2008 MT X3 RIP you were a faithful sidekick and will be missed.
2007 AT X3 RIPOS
2005 GC
2000 Jeep Cherokee
1997 Twin Turbo RX-7
1984 GTI Wolfsburg Edition Neuspeed and more

Last edited by Evlengr; 10-16-2011 at 11:10 PM.
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