# Speed dependant volume

Show 40 post(s) from this thread on one page
Page 2 of 2 First 12
• 10-14-2003, 03:49 PM
SjLucky
yes it can be done gavinzbits
• 10-15-2003, 06:48 AM
gavinzbitz
:o)))))))))))) How???? Is anyone willing to do it?
• 10-15-2003, 08:06 AM
GingerPrince
Quote:

Originally Posted by gavinzbitz
:o)))))))))))) How???? Is anyone willing to do it?

It would be fairly straightforward to do. You'd just need some code in your app (or even run it as a separate program that adjusts master volume) that reads NMEA strings from your serial port to get your speed, and calculate volume based on that.

Say you wanted volume to vary linearly from 75% when stationary to 100% when at 60mph + you could implement this pseudocode: -

GET speed FROM NMEA DEVICE
newvolume = 75 + (25/60) * speed
if newvolume > 100 then
SET MASTERVOLUME = 100
else
SET MASTERVOLUME = newvolume
end if

Do this ever second or whatever and you have your solution. Main problem would be that you wouldn't (I don't think) be able to do this at the same time as running GPS software, they wouldn't both be able to view the serial port.

Now maybe you could program this applet to forward all the NMEA strings to a virtual serial port or something and have your GPS software map to this, but this is beyond my skills (not being a programmer) so not sure if you could or not.
• 10-15-2003, 09:33 AM
tejesh83
Why stop there? Let ME control the speed of your car too.

cruisespeed = 75
GET currentspeed FROM NMEA DEVICE
if currentspeed < cruisespeed then
SET ENGINERPM += 100
end if
if currentspeed > cruisespeed then
SET ENGINERPM -= 100
end if
if currentspeed > SPEEDLIMIT && POLICE then
SET ENGINERPM -= 10000000
APPLY BRAKES
end if
• 10-15-2003, 09:41 AM
Ricky327
But the speed of the car dont have much to do with the car noise. How about the engine speed? surrounding traffics? kids at the back? So you cant just adjust the volume based on car speed.

what keeps the circuit from pickin up your music as the noise? if that was the case then you would blow everyone of your speakers and might cause some earing damaged if it isnt shut off quickly.

You knows whats being played on your PC so from there it just a matter of rejecting those signals. You need to sample the noise and the music inside the car using a mic. You know the sound comming out of the PC. Do some DSP trick on both signals...and there you have it a filtered out noise :D Just adjust the volume based on the level of this noise.

So simple...LOL maybe not in reality.
• 10-15-2003, 10:17 AM
CarComp
This may end up being an option when we write our GPS module. We won't have to worry about conflicting with another GPS application, cause it will be integral with m.e.
• 10-18-2003, 11:10 AM
gavinzbitz
Is this the GPS module that will be based on Destinator code?? Or is that something completely different?
• 10-19-2003, 07:33 PM
Maxis24
Trust me guys, you don't want to have an automatic volume increaser. As my aviator suggests, I own a Focus and the stock radio system uses the "volume leveling" technology. It is a nice system because it allows the auto maker to save \$\$\$ when producing a vehicle because they don't have to provide as much sound deadening material. The downsides to the system is that if the volume is up high already, the volume will be turned up to the point where it begins to blow your speakers. They system is also flawed because the ECU sends weird signals to the radio when transitioning from reverse to drive (sometimes) that result in volume being maxed out for 1/6th a sec.

It is an interesting idea, but I have yet to find an execution of this system that I actually liked. Feel free to prove me wrong though. ;)
• 10-19-2003, 08:40 PM
QuickCarl
My GM HU already has speed variable volume. :D Guess that is an advantage of having my Truckputer connected to the Aux using the PIE adapter. ;)

Don't other aftermarket pieces have that?
Show 40 post(s) from this thread on one page
Page 2 of 2 First 12