Installation Complete
I ended up purchasing a 60Wx4 amp, (Profile amp from Crutchfield). It's a rather inexpensive amplifier, but I have it powering the stock speakers from the stock headunit on my 2006 3, so anything more expensive probably wouldn't help much. It has only been a few days since I finished the installation, but so far I am very happy with the results. The stock speakers now get much louder with MUCH less distortion than when they were only powered by the headunit. I'm sure if I had installed new speakers and a new headunit the sound would be even better, but for my purposes I am very pleased.
I had a lot of trouble with alternator whine and other noise in the signals. I found that most of it was caused by the Scosche 4-channel LOC from Crutchfield. The reviews on Crutchfield's site for this LOC are strong, but I am disappointed with it. It has an adjustable gain for each channel, but anything above the absolute lowest setting caused a massive amount of noise (it has a ground wire that does nothing to fix this). It is also rather bulky and I had a miserable time trying to get it to fit in the dash. The plastic casing also broke before I had even hooked anything up to it.
Other than that, it has worked out well and I recommend this fairly cheap option to anyone who doesn't really want to tear apart their doors to install new speakers but wants a better sound.
I ended up purchasing a 60Wx4 amp, (Profile amp from Crutchfield). It's a rather inexpensive amplifier, but I have it powering the stock speakers from the stock headunit on my 2006 3, so anything more expensive probably wouldn't help much. It has only been a few days since I finished the installation, but so far I am very happy with the results. The stock speakers now get much louder with MUCH less distortion than when they were only powered by the headunit. I'm sure if I had installed new speakers and a new headunit the sound would be even better, but for my purposes I am very pleased.
I had a lot of trouble with alternator whine and other noise in the signals. I found that most of it was caused by the Scosche 4-channel LOC from Crutchfield. The reviews on Crutchfield's site for this LOC are strong, but I am disappointed with it. It has an adjustable gain for each channel, but anything above the absolute lowest setting caused a massive amount of noise (it has a ground wire that does nothing to fix this). It is also rather bulky and I had a miserable time trying to get it to fit in the dash. The plastic casing also broke before I had even hooked anything up to it.
Other than that, it has worked out well and I recommend this fairly cheap option to anyone who doesn't really want to tear apart their doors to install new speakers but wants a better sound.
