No, they're not. A few manufacturers have used 8ohm speakers in the past in their cars. Volvo was one--700 series cars had a 3-3.5" speaker on the dash that was 8ohm. I had major issues with my first one due to this. The 3.5" Infinity Kappas I replaced the stock ones with were overpowering (soundwise much louder) due to this.I'm pretty sure some BMWs and Mercedes also did this. Chevy did it a long time ago in some of their luxury model cars (those with premium audio.)Its usually on smaller speakers located on the dash, but I have heard of rear speakers setup this way also. At 8ohms they draw less power, thus sound softer. It's a cheap primitive way to control imaging.
