Notices
Scion tC 1G ICE & Interior In-car entertainment and electronics...

Audible tachometer?

Old Apr 22, 2008 | 08:23 PM
  #1  
KingPadmei's Avatar
Thread Starter
Member
10 Year Member
5 Year Member
SL Member
Team ScioNRG
 
Joined: Jul 2007
Posts: 87
From: York, Maine
Default Audible tachometer?

So I just bought a navigational system, and I am extemely happy with it. However, the audio sounded terrible on it. I figured out that it was the FM transmitter just being bad quality, so I hardwired it. Now I get a semi loud whine, that has a pitch that directly corresponds to my RPMs. Anyone head of this before?
Old Apr 22, 2008 | 08:33 PM
  #2  
tweetertc's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
Scion Evolution
 
Joined: Feb 2006
Posts: 566
From: Chicago, IL
Default

yes.... its called an alternator whine... you need a better ground for all the devices involved...
Old Apr 22, 2008 | 09:08 PM
  #3  
theunclesam's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Dec 2006
Posts: 596
From: Streamwood, IL
Default

It's called a ground loop and it's a pretty easy fix. Just like tweeter said, better grounds or a common ground will fix it.
Old Apr 22, 2008 | 09:15 PM
  #4  
Sciontistical_One's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (2)
 
Joined: Jan 2008
Posts: 1,557
From: O.C. SoCal
Default

Wow, I saw the title of the thread and already started thinking about a device that reads your RPM's out loud when you hit redline, kinda like Mr. Zulu's voice coming from the dash... "Warp 2.7... Warp 2.8..."

(I'm at work and it's uber-slow today...)

Maybe KITT's voice from Knight Rider...
Old Apr 22, 2008 | 10:10 PM
  #5  
engifineer's Avatar
Senior Member
10 Year Member
5 Year Member
Scikotics
SL Member
 
Joined: Nov 2004
Posts: 9,731
From: Minneapolis, MN
Default

Sssshhhhh! some idiot that is going to someday work for toyota will hear you and design that.. then we will have one more noise making item in the car

I swear, between seatbelt chimes, key in the ignition with door open chimes and alarms that make noises (which thank god the scion security does not) cars get more annoying every day
Old Apr 22, 2008 | 11:42 PM
  #6  
KingPadmei's Avatar
Thread Starter
Member
10 Year Member
5 Year Member
SL Member
Team ScioNRG
 
Joined: Jul 2007
Posts: 87
From: York, Maine
Default

Ok, so next question, I am not exactly super savy with all this, how am I to do that? As far as I know, the only thing I have thats grounded that I installed is my amp. So what am I doing here?
Old Apr 23, 2008 | 02:06 AM
  #7  
engifineer's Avatar
Senior Member
10 Year Member
5 Year Member
Scikotics
SL Member
 
Joined: Nov 2004
Posts: 9,731
From: Minneapolis, MN
Default

Your ground needs to be connected as close to the amp as possible (shortest ground wire you can use) and to a good solid piece of metal. So no metal/machine screws. More like a seat bracket bolt or something else that is bolted to a solid piece of the chasis. The metal that the ground is connected to should also be free of paint.
Old Apr 23, 2008 | 02:12 AM
  #8  
iKONA's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Feb 2007
Posts: 2,741
From: South Chicago
Default

Originally Posted by Sciontistical_One
Wow, I saw the title of the thread and already started thinking about a device that reads your RPM's out loud when you hit redline, kinda like Mr. Zulu's voice coming from the dash... "Warp 2.7... Warp 2.8..."

(I'm at work and it's uber-slow today...)

Maybe KITT's voice from Knight Rider...
Lol I was thinking the same and thinking that must be annoying.
Old Apr 23, 2008 | 04:51 AM
  #9  
BZinn1's Avatar
Senior Member
10 Year Member
5 Year Member
Balliztik
SL Member
 
Joined: Jun 2007
Posts: 9,538
From: Washington
Default

Warp 2.8.........must be turbocharged.........my NA only gets warp 1.4..........
Old Apr 23, 2008 | 05:02 PM
  #10  
KingPadmei's Avatar
Thread Starter
Member
10 Year Member
5 Year Member
SL Member
Team ScioNRG
 
Joined: Jul 2007
Posts: 87
From: York, Maine
Default

It can't be my amp because the sound works perfect if I don't have the AUX plugged in. Also, I have a 3in cable leading directly to a screw thats screwed into my chassis. I think its grounded ok. The only thing that isn't grounded is my Scoche thing that I got at walmart for like $6 to wire my amp into my back speakers. But it also has worked perfect for months, and still works if I am not using AUX, and if anything this noise is coming from the front speakers.
Old Apr 23, 2008 | 05:42 PM
  #11  
KingPadmei's Avatar
Thread Starter
Member
10 Year Member
5 Year Member
SL Member
Team ScioNRG
 
Joined: Jul 2007
Posts: 87
From: York, Maine
Default

Now that I know the wording to use I went through my barrage of searches and I just bought a Ground Loop
Isolator. Will let you guys know if it fixes it.
Old Apr 23, 2008 | 06:08 PM
  #12  
theunclesam's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Dec 2006
Posts: 596
From: Streamwood, IL
Default

^^^ It might fix it, but in my experience, it doesn't. You should read more about what a ground loop is, and how it's caused. Then you can begin to troubleshoot your problem.
Old Apr 24, 2008 | 02:30 PM
  #13  
KingPadmei's Avatar
Thread Starter
Member
10 Year Member
5 Year Member
SL Member
Team ScioNRG
 
Joined: Jul 2007
Posts: 87
From: York, Maine
Default

Ok, didn't end up getting one. I tried moving some cables around to no avail. Not sure what I need to do here....
Old Apr 24, 2008 | 05:44 PM
  #14  
theunclesam's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Dec 2006
Posts: 596
From: Streamwood, IL
Default

Just to make sure, is the sound coming from your door speakers or through your sub? Also, if your door speakers, do you have an amp hooked to those, or do they get their sound directly from the navi unit?
Old Apr 24, 2008 | 06:34 PM
  #15  
KingPadmei's Avatar
Thread Starter
Member
10 Year Member
5 Year Member
SL Member
Team ScioNRG
 
Joined: Jul 2007
Posts: 87
From: York, Maine
Default

The sound is coming from my front speakers as far as I can tell, and my sub is hooked to the back speakers, so its not my sub I don't think. It has something to do with my center console AUX jack and my cigg lighter ports. I thought maybe it was because I was running the power cord for my Navi right next to the AUX audio wire, but I have since moved it and the sounds remains.
Old Apr 24, 2008 | 07:52 PM
  #16  
theunclesam's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Dec 2006
Posts: 596
From: Streamwood, IL
Default

Is this a portable navi unit or one that you replace the factory radio with (installed)?
Old Apr 24, 2008 | 08:05 PM
  #17  
KingPadmei's Avatar
Thread Starter
Member
10 Year Member
5 Year Member
SL Member
Team ScioNRG
 
Joined: Jul 2007
Posts: 87
From: York, Maine
Default

Portable
Old Apr 24, 2008 | 08:10 PM
  #18  
theunclesam's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Dec 2006
Posts: 596
From: Streamwood, IL
Default

ah..my thinking about this has become very clear dude. :D

Your problem is the fact that your portable unit gets its power from your cig plug, or that one under the armrest (right?). If so, this is causing the ground loop as the grounding on this plug probably isn't so great.

Can you adjust the level of the input? (I dont have a factory radio, so I'm not sure if you can..).

If so, you could turn the navi volume down a bit, and turn the level input on the factory radio up.
Old Apr 24, 2008 | 08:16 PM
  #19  
KingPadmei's Avatar
Thread Starter
Member
10 Year Member
5 Year Member
SL Member
Team ScioNRG
 
Joined: Jul 2007
Posts: 87
From: York, Maine
Default

Actually thats worse. The noise appears to remain consistant with the radio volume, so tunring down the navi just makes the noice more noticable. However, if I turn the navi up, it makes a scratchy noise from my tweeters.
Old Apr 24, 2008 | 08:19 PM
  #20  
theunclesam's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Dec 2006
Posts: 596
From: Streamwood, IL
Default

But if you unplug the navi, everything is fine?

Will the navi unit run without being plugged in (batteries)?

If so, try this test:

1. Plug the navi into the aux port without being plugged into power

2. Try an iPod or something in the aux port without being plugged into power

3. Try the same device as above, but power it from the same port as the navi

That will determine if it's the navi, power, or the aux plug that's causing the problem.

Thread Tools
Search this Thread

All times are GMT. The time now is 10:15 AM.