Forgive me if this idea has been here before, I strongly suspect it has been.

I am forever adjusting my car stereo volume to compensate for road noise. Stop at a traffic light, turn down the stereo. Start moving again, gotta turn it up (this is with the windows up). And when i get into my car first thing in the morning, the radio comes on at an unbeleivable level, that was somehow bearable when I drove home the night before.

Why not make the radio volume vary with the speed of the car? It would be very easy to run a digital signal from the speedometer to the radio that adjusted the volume based on vehicle speed. And it would probably be easy work for an audio engineer to determine the speed to ambient noise ratio for a specific vehicle type, so each model of car would have the right setting.

If you really wanted it done right, you could put an ambient noise sensor in the cab of the car, and base the stereo volume on that, so that it isn't based only on speed, but by interference.

Naturally, this would come with an override, or you could adjust the parameters of the correction yourself.
-- Xoebe, Jul 28 2003

Sound effects http://www.interstudio.co.uk/sndchk.htm
But what if you're listening to a CD of "road noise"? [Amos Kito, Oct 04 2004, last modified Oct 21 2004]

The SkyLine series from Blaupunkt http://www.bluespot.co.uk/skyline.asp
With models that have "Self adjusting equalisation via included microphone" and "Speed-dependant sound adjustment" [phoenix, Oct 04 2004, last modified Oct 21 2004]

VDO dayton CD4802 (.PDF) http://www.vdo.dk/d...radios/cd4802gb.pdf
With Speed Dependent Volume Control [phoenix, Oct 04 2004, last modified Oct 21 2004]

High quality $ystems have this, and it's standard in some luxury vehicles. However...
why not have an after-market version? A portable device that can sense the engine speed, and adjust the volume via remote control, for radios that use a remote.
If not tach speed, it could "listen" for road noise, to correct the volume. With the radio off, drive around, and the device learns the sounds of your car. It still needs to account for which windows are open, convertable top down, tire chains, etc.
-- Amos Kito, Jul 28 2003


It's called ASL (automatic sound levelizer) and it is indeed baked. I don't know how it works.
-- snarfyguy, Jul 28 2003


On my car both the radio volume and the intermittant wiper speed are slaved to the vehicle speed. Handy features.
-- ry4an, Jul 28 2003


All GM's have this , it's call SCV ( speed volume control).
-- SystemAdmin, Jul 28 2003


Yeah, I have a Blaupunkt headunit with a wire that your supposed to hook up to the speedometer somehow and it will automatically adjust the volume based on speed. My problem is my car is a standard and its the engine noise, not road noise that drowns out the music. Is it possible to hook this wire up to the tachometer instead? And how is this wire attached anyhow? My Civic's factory deck didnt have this feature, so obviously there are no wires in my car ready to be hooked up to this feature. I also have a Town Car that I had this deck in. Does anyone know how to hook cars up? 02' Civic 88' Town Car. Thanks
-- Palace, Oct 22 2003


You have a 'town' car, meaning it gets town everywhere by a tow truck?
-- mecotterill, Apr 08 2008


I would prefer to be able to control other peoples' stereo systems.
-- james_what, Apr 12 2008



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