for now I am using my seat bolt as my amp ground. When I have time I am going to do the "big 3". I was going to run a ground strap from the seat bolt to the jack bolt to ensure a good ground. Good idea? Bad idea?

 

Oddly enough the ground at the bottom of the seat area does provide sufficient grounding. If you would like to add some extra insurance against noise here is what I would recommend.
It is the difference of potential between the ground of the amplifier and the tuner or head that is the source of much inter component noise in many systems. Since the amplifier has the potential for requiring the most current use the amplifier's ground for the whole systems ground. Remove the (-), Black ground lead from the chassis terminal under the dash, and connect it directly to the amplifiers (-) or GND terminal. The power leads may remain connected as normal. Ground all other electrical components to this amplifier ground too.

 

DOES ANYONE SEARCH ANYMORE?!?!?

 

WHAT?!? Please dont be saying what I think you are... (thats not me bowing. Thats me slamming my head into the GROUND)

Ok. The seatbelt is not an appropriate ground. PERIOD!

DO NOT run a ground from your HU to your amp ground like he is saying....

 

Here it is, short and sweet:

1. Seat bolt ground - BAD, Body Ground - GOOD
2. Do the big three. Took me less than 1 hour (I spent over 20 hours on my install) and around $25.
3. Enjoy the peace of mind that comes from knowing you didn't take shortcuts, and don't have to worry about the system you just spent all that time and money on sounding like CRAP!!!

I think number three is worth 1 hour of your time and $25, but that's just me.

 

You need to stay around!

 

Ground Bolt:
This is not a bad idea if you are restricted to installing the amplifier under a seat or bench. However there are always caveats to installing equipment. The "seat bolt" hopefully means the bolt/nut that fastens the seat directly to the base-floor-chassis.
Establishing a firm and consistent ground under a seat is difficult unless you know what tools are available to him.
STAR Ground:
The connections scheme that always results in the lowest noise potential is the "star" ground system. That is all grounds by design are taken individually to one common terminal point.
Since current through any wire or cable causes voltage drops any voltage drop should be minimized through the lead that will carry the most current. In this case the additional amplifier will (by design) carry the most current,and its' ground point will be the lowest potential of the system.
Since the head/receiver appears "ahead" of the amplifier any noise voltage generated in the ground lead(s) will be amplified by the Audio PA. It is wise to directly ground the head to the amplifiers "ground" terminal. This is a wiring scheme for "proof of performance" systems where there should be as low a noise floor as possible .
There is absolutely nothing wrong with my theory or application; however doing it can be a hassle in some installations. When you cannot take chances of having extraneous noises within professional systems; what I had specified is best.
High performance Bio-medical,Satellite-Telecommunications,and Audio/Video Remote trucks are designed this way for exactly the reasons given.

 

Here we go again...

 

There are parts of this that I agree with and parts that I dont. I believe in the theory of STAR grounding (although, I dont believe in runnin a new ground from the deck to the amp...overkill). I will give you that much, but those vehicles that you listed do NOT attach to a seat bolt for their ground point. As has been said numerous times on this board, seat bolts/jack bolts/seatbelt bolts etc are notoriously bad grounds. Shoddy tack welds, glued-together body panels, that grease they put on the threads on some of those bolts...all those factors lead to very high resistance between the bolt and battery. Most of the time, your best bet is to scrape some paint off the body, drill a hole and nut-and-bolt the ground to the body. I have a write up in another thread about how to check the resistance from the proposed ground spot to the battery, and it never fails to yield an excellent ground.

Lets not let this thread get to where the last one on the grounding subject went.

 

Crewwzin: I absolutely agree with you concerning your response,but as mentioned in my post that there are caveats with any installation. I didn't think that grounding would cause so much controversy.

Understand this from my history. I absolutely hate to specify an installation only to be "bit" later by undefinable noises such a buzz,pops, ticks,and oscillations that occur when various components are operated. Some of the systems that I design or have designed for industry have ranged from TV News Trucks up to ESPN Remote Transmission facilities.
I was trying to give an answer based on my experiences in this industry.
Peace.

 

You really have no idea. The labyrinth of pain you have stepped into when discussing grounding is rivaled only by the fires of hell itself. Even Satan wont get into a grounding discussion!

Read this thread and you will know what I'm talking about

I dont doubt your expertise, what I do doubt is the realibility of a seat bolt for grounds in high current draw applications. I have personally tested my truck with a DMM and found the seatbolts/jackbolts/any other factory bolts to have a resistance of >15 ohms. This is a textbook bad ground. Less than 1 ohm is nominal. I scraped some paint off the body and tested that...guess what, .6 ohms.

To the OP, the above thread is also the one in which I wrote out the procedure for testing said grounds. Maybe it will help you in your quest to a rockin system. Good Luck!

 

Ok, just finished reading up on this thread, but wanted to get some input here. Maybe the way people are using seat bolts is different from what I have in the past, but it seems to be a combination of the above and I wanted to see if I was going about it right.

Usually I'll remove the bolt, then use something...wire wheel, dremel, something, to remove the paint from where the bolt contacts the body panel. Then I'll fasten my ground between the body and seat bracket. It's being held by the seat bolt, but is in direct contact with the body panel. I haven't had any problems to date...but I also am far from a professional installer and certainly don't put together comptetition systems. I'm just curious...would this be a bad idea here?

BTW, I'm always cautious about drilling new holes. I have the inate ability to screw up even the simplest things...and there's way too much I can screw up drilling into the floor.

 

I did just what you did. I removed both jack bolts and wire wheeled the paint around the hole aswell as the bolt itself. I used one for the ground cable and put a ground strap from one to the other to ensure a good ground using star washer on each. Seems to work good with both amps.

 

Why just not take less time and put 1-2 screws down with clean metal and star washers into the body...??? And if you want to ground strap it, do that also... But take out the bolts is WAYY more work and less reliable.

 

I have installed a sum total of 1 system, so I wouldn't even qualify as a novice in this area, but I just don't understand why you would want to do an installation in a way that has caused numerous people trouble in the past. Will it work for you? Maybe, maybe not, but it literally takes less time to drill, remove the paint, and bolt down to the body than it does to do what you have described.

Again, I'm far from an expert in this field, but from all the years I have spent working on cars I've found if there is Option A that will work 70% of the time without a problem and Option B that will work 99% of the time without a problem, then the only reason to choose Option A would be if it is much cheaper and/or takes much less time. In this case Option B takes no more time (less probably), and costs no more money, so why choose Option A.

That's just how I approach these kind of issues, but then again, what do I know.