the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
icon

Automatic Volume Control for all cars


Post ReplyPost New Topic
< Prev Topic Next Topic >
710- 
Member - Posts: 6
Member spacespace
Joined: February 02, 2006
Location: Belgium
Posted: April 08, 2006 at 2:09 PM / IP Logged  

I have searched for this but can’t find anything.

Can somebody please tell me how to make an Automatic Volume Control so that as the noise level in the car increases, the volume will increase too.

I have a car with speakers/amps in the doors. The head unit only supplies the signal.

I would like to make something with an adjustment knob that goes in between head unit and the amps. I would install a mic in an appropriate place and adjust the sensitivity of it to give the Volume Control a base line. Then as the interior noise of the car goes up, the volume input of the amp is increased.

If I increase the sensitivity of the mic, the volume would increase more than before, given the same noise level.
Automatic Volume Control is available on some of the mid/high end car stereos, but not on the radio I like (or the ones I already own).
I would like to make one for all my radios.

Thanks

KPierson 
Platinum - Posts: 3,527
Platinum spaceThis member consistently provides reliable informationspace
Joined: April 14, 2005
Location: Ohio, United States
Posted: April 08, 2006 at 2:39 PM / IP Logged  

The approach I would take would be to build a circuit to monitor the mic (if you have your heart sat on using a mic, I personally would base it off of the vehicle speed sensor).  Then, you would have to access the volume up and volume down functions of the radio in question.  You may be able to do this by soldering some wires on the main circuit board of the radio, although it would be very hard to find where to solder (especially if a detachible face is installed).  You other option would be to hack up an old remote control and use it to send IR commands to your radio to raise volume.

I wouldn't go with a mic as it would be hard to set it correctly, especially if you really feel liking cranking the radio one day (the mic would pic up the loud music and try to turn your radio up louder, causing a higher noise floor, resulting in a louder radio and so on).  By using the speed sensor you can adjust volume based on vehicle speed, which would provide a more predictable result.

Kevin Pierson
audiocableguy 
Copper - Posts: 630
Copper spacespace
Joined: January 27, 2003
Location: Idaho, United States
Posted: April 08, 2006 at 2:52 PM / IP Logged  
I own a Mercedes with a Bose system that has this feature and I wish it didn't. No way to disable it. Many times I have wanted to rip the deck out due to this "feature".
Anyway some systems use the vehicle tach wire to tell a VCA (voltage controlled attenuator) to raise or lower volume.
firstrax 
Copper - Posts: 113
Copper spacespace
Joined: January 18, 2006
Posted: April 08, 2006 at 3:00 PM / IP Logged  

I'm with kevin. Pull the speed.

With a mic your going to need some sort of hysteresis circuit to keep the volume from adjusting with the frequency of the noise or every time you hit a bump. Plus you will need to filter out the sound from the stereo

Check the Texas Instruments web site for AGC circuits. Might be something there. Or, if you have experience with micros, pull speed from the OBD port and adjust a digital pot accordingly.

710- 
Member - Posts: 6
Member spacespace
Joined: February 02, 2006
Location: Belgium
Posted: April 08, 2006 at 4:40 PM / IP Logged  

Thanks.

I was going to put the mic behind the radio under the dash/center console because then it would not pick up the radio emissions as much. The general rumbling of the car would be there though and it would increase as speed etc increased.

I'll have to see if i can get to the tach or speedo to take a reading off those.

It's certainly going to be more involved that I first thought. but I hate having to constantly adjust the volume on this car. It's a sports car and makes slightly more noise than the average sedan.

Thanks for all your input. I will keep looking at his.

jeffchilcott 
Platinum - Posts: 2,483
Platinum spacespace
Joined: April 11, 2002
Location: United States
Posted: April 08, 2006 at 5:56 PM / IP Logged  
I would just go buy a good pioneer deck that already has it built in.   I know the older 860mp's and 8600mp's have it......It seams like alot of work when thier are aftermarket decks that have it built in
2009 0-1000 Trunk WR 154.0DB 2009 1001+ Trunk WR
2007 USACI World Champion
2007 World Record
2006 USACI Finals 2nd Place
stevdart 
Platinum - Posts: 5,816
Platinum spaceThis member has made a donation to the12volt.com. Click here for more info.spaceThis member has been recognized as an authority in Mobile Audio and Video. Click here for more info.spaceThis member consistently provides reliable informationspace
Joined: January 24, 2004
Location: Pennsylvania, United States
Posted: April 08, 2006 at 6:47 PM / IP Logged  

Turn it up loud all the time.  No need for adjustments when you've got it pegged already!

But really, I'd hate to see your experimental work end up frustrating you in the long run.  Spend some time in the car mentioned above and find out how annoying it can be.  My take is this:  adjustments are already "automatic" because we have the inate ability to compensate.  When the noise threshold gets louder, we automatically compensate for that noise.  When we watch TV lying down on our side, we compensate for the different viewing angle...and we would be annoyed if the TV tilted when we tilted our head.  Same thing with our hearing.

With either type of electronic compensation, there will be drawbacks because of the battle with your own compensatory tendencies.  When you shift through the gears from 0 to cruising speed, the noise threshold will increase, fall, increase, fall through the gearing and the subsequent higher/lower RPMs.  With mic sensoring, the music will increase and fall through these gear changes.  Speed sensoring would at least increase slightly during the gearing and be at max loud primarily to combat road/wind noise, but that has been proven to be annoying in the Bose systems that use it.  In any case, write up something in the end if you've gone ahead and built it and lived with it for awhile.  I would be interested to find out what you think.

Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.
boardinbum 
Silver - Posts: 358
Silver spacespace
Joined: February 07, 2005
Location: United States
Posted: April 08, 2006 at 7:37 PM / IP Logged  
Someone help me understand...
Why would you want the stereo's volume to increase as the interior noise increases? Wouldn't that mean, when you try to talk, it gets louder?
Wouldn't it be easier [and still pretty convenient] to just have controls up on your steering wheel or something?
710- 
Member - Posts: 6
Member spacespace
Joined: February 02, 2006
Location: Belgium
Posted: April 09, 2006 at 3:49 AM / IP Logged  

Yes, you all have valid points and I’ve done some thinking about it.

First, it will be complex to build, beyond my capabilities (input from tach, speedo, mic, with some programming etc…)
I have come to the conclusion that I already have an automatic volume control, me. Like you said.

If I had a steering volume up and down on the steering wheel it would have to be the easier way and I probably would never posed this question.

The car is a 1991 Honda (Acura) NSX, no volume controls on the steering wheel. The car is somewhat noisy, it’s not modified and quite civilised but its noise level changes dramatically.

1) Actually the different noise levels between driving slowly and fast are great (wind noise).
2) And the difference noise levels between engine idle and rev-ving it during acceleration are great (engine noise).

1+2=10

These two effects combined mean a huge difference in noise level and constant radio volume adjustment.

So when I’m listening to the radio at a light, for example, then accelerate off, I need to constantly adjust the volume on the radio which is not easily accessible, it is low down on the dashboard.

Most owners of these cars don’t complain about this problem because they have the car as a Garage Queen, they only drive it occasionally.

But for me it’s my daily driver.

I thought of installing a couple of speakers on either side of the head rest, then the relative difference  in sound volume would be less (I can imagine) because they are closer to my ears than the door speakers way far away low down in the far corners of the doors.

Then I thought of the Automatic Volume Control. Then fitting steering wheel volume controls.

There are cruise control buttons on the steering wheel; I almost never use the cruise control.

Maybe I could re-wire the buttons to increase decrease the volume, possible on a separate toggle switch or button. 90% of the time it would be on the radio setting, the rest on the cruise control.

Or actually install two micro buttons on the steering wheel. But might look ugly. Have any of you seen nice aftermarket steering volume buttons?

The radio  I have in there now has a remote, but it’s not so handy to use, and I’ve clipped it to the wheel, but it’s not the way to go.
Too big and clumsy.

Small flat pressure buttons would be better, I could place them discreetly in one of the openings in the steering wheel.

That coupled with the speakers closer to my ears might be the way.

Peter

speedwayaudio1 
Silver - Posts: 879
Silver spacespace
Joined: March 18, 2003
Location: United States
Posted: April 09, 2006 at 4:02 AM / IP Logged  
I just keep my remote on my lap and turn it up and down as I need to.
Big Dave
Page of 2

  Printable version Printable version Post ReplyPost New Topic
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot delete your posts in this forum
You cannot edit your posts in this forum
You cannot create polls in this forum
You cannot vote in polls in this forum

  •  
Search the12volt.com
Follow the12volt.com Follow the12volt.com on Facebook
Thursday, October 31, 2024 • Copyright © 1999-2024 the12volt.com, All Rights Reserved Privacy Policy & Use of Cookies
Disclaimer: *All information on this site ( the12volt.com ) is provided "as is" without any warranty of any kind, either expressed or implied, including but not limited to fitness for a particular use. Any user assumes the entire risk as to the accuracy and use of this information. Please verify all wire colors and diagrams before applying any information.

Secured by Sectigo
the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
Support the12volt.com
Top
the12volt.com spacer
the12volt.com spacer