Car Stereos: rear speaker replacement, monsoon system, oem replacements

Question
2002 Grand AM GT with Monsoon system has blown rear speaker.  Rears have 4 wires going to each speaker.  What type of replacement speakers do I need?  Some installers are suggesting standard 2 wire speakers and say they will correct the wiring to use these speakers.  I feel the original intent of the system will be lost if I do this.  My choice for exact replacement speakers may be limited and I want to know what type of speaker I am searching for.

Answer
Hi Nick,

Your Grand Am's Monsoon system uses separate outputs from the factory amplifier to send low frequencies directly to the stock woofers, and higher frequencies directly to the stock "tweeters".  Unfortunately, it's pretty common for the factory speakers to fail; either producing no sound at all, or lots of crackle/distortion on bass notes.  You can purchase OEM replacements, but there's no guarantee you won't have the same problem again later.

After-market speakers with bi-amp capability are rare, but there are a few out there.  Soundstream's SST6.9, for example, would allow you to make separate connections for the woofer and tweeter.  Other 6x9" 2-way and 3-way speakers can be bi-amped if you modify the speaker; ie, locate the wires running to the midrange/tweeter pod and cut them away from the main terminal block so they can be wired separately.  I've done this with a few different speakers, and gotten good results in this type of system; but it's worth noting that you'll instantly void the speaker warranty by doing this.

Alternately, you can purchase a standard 6x9" speaker and just connect it to the wires carrying the low-frequency audio, leaving the high frequency outputs disconnected in the rear.  This might be worthwhile if you're just looking for a way to keep the bass and get rid of the distortion from a blown speaker, but you won't get any more upper midrange and treble except for your front speakers.  Some people actually prefer this type of arrangement, but it's a matter of personal preference.

Because the Monsoon system uses a high-level input from the factory radio, it's possible to bypass the rear amp channels and connect after-market rear speakers directly to the head unit's outputs.  This will allow the rear speakers to play a full-range sound through two terminals, but you may lose some bass output, and the maximum volume is likely to be reduced.

Hope this helps!

Brian