Originally Posted by
chinamaniac
ehhh , not sure, I know radar detectors are popular but maybe not for something like that.
How about a GPS with a radar detecor built in
A good car stereo guy can usually (or used to be able to; hard to say with the complexity of built in audio systems in high end cars) find a way to make an audio interrupt of the stereo system, an override of whatever is playing so that the device of your choice has priority. There definitely used to be audio override adapters available, but I've been out of the car stereo bidness for almost a decade now. You may need to be a little picky about which brand/model scanner you use, but I have no doubt that there are still companies doing this type of shit. Metra, PAC, I'm drawing a blank on some of the companies that used to make things like CD/stereo adapters for cars, but crutchfield should be able to help with that. No idea about the wrist band, however.
The high end Escorts have built in mics and can be set to figure out the ambient noise going on in your car, and get louder or softer accordingly, as set by you. Or you can just pre-set the volume to always be the softer than the factory pre-sets.
You could probably find a place that specializes in doing custom stuff for deaf people who are used to making sound information into light, pictures, vibrations, shit like that. They may not have done exactly what you are talking about before, but they've probably done similar shot for alarm clocks and junk like that, so they may very well have some easy solutions.