Toyota FJ Cruiser Forum banner
1 - 20 of 20 Posts

·
Registered
Joined
·
205 Posts
Discussion Starter · #1 · (Edited)
OK this is what I've had since last year...

Pioneer AVH-P6800
Fosgate punch 500 amp for sub
Fosgate punch 12" P2 in Q-logic box
Fosgate p450.4 4 channel amp
Components in the front, infiniti 3" in the rear

I've had noise since all that was put in, I went back and forth to circuit city 5 times, they made sure there was no ground loops, they moved the amp around, changed the grounds, re-ran the power wires farther from the RCA's...I sent the amp back and crutchfield sent me a brand new one, STILL NOISE...finally circuit city put RCA filters on, and it helped but I still had noise and just got used to it...

Recently I replaced the AVH-p6800 wit a Kenwood DNX 8120, and the Q logic box with the wicked cas box. I had the best local shop re-wire the 4 channel amp, they did a quality job (they work one imports, luxery cars, and do alot of custom work)...after two seperate times of trouble shooting there was still noise...I checked everything my self and the power wires are run separately, the ground is short, the noise filters are still on the RCA's (they even put on newer higher quality ones)...and there IS STILL NOISE... Finally they tinkered with the amp, and connected it to a single test speaker, and THERE WAS NOISE...so the shop is basically saying its my amp, which has already been replaced once...the last thing they did that helped a lil bit leave the amp unmounted, its just resting on the plastic under my passenger seat

Basically they said fosgate's sometimes make alot of noise...

My question is, what brand or maybe what model is notorious for good noise reduction...I need atleast 65 watts x 4 RMS at 4ohm (would like more)...and I don't want to spend more than 500...

I've read the JL A4300 is really good at noise reduction, but its really weak on power...

Also, alot of people have told me 4 channel amps are notorious for producing noise in big block V6's and V8's...is that true?

Any help would be good, and don't flame me if this has been posted before, i did the best searching i could, and found alot of trouble shooting on fixing noise, but nothing on the best amp for keeping noise low...:cheers:

OH almost forgot, the noise is a soft buzz, with a whine in the background that gets higher pitched with RPM's
 

·
Registered
Joined
·
5,027 Posts
OK this is what I've had since last year...

Pioneer AVH-P6800
Fosgate punch 500 amp for sub
Fosgate punch 12" P2 in Q-logic box
Fosgate p450.4 4 channel amp
Components in the front, infiniti 3" in the rear

I've had noise since all that was put in, I went back and forth to circuit city 5 times, they made sure there was no ground loops, they moved the amp around, changed the grounds, re-ran the power wires farther from the RCA's...I sent the amp back and crutchfield sent me a brand new one, STILL NOISE...finally circuit city put RCA filters on, and it helped but I still had noise and just got used to it...

Recently I replaced the AVH-p6800 wit a Kenwood DNX 8120, and the Q logic box with the wicked cas box. I had the best local shop re-wire the 4 channel amp, they did a quality job (they work one imports, luxery cars, and do alot of custom work)...after two seperate times of trouble shooting there was still noise...I checked everything my self and the power wires are run separately, the ground is short, the noise filters are still on the RCA's (they even put on newer higher quality ones)...and there IS STILL NOISE... Finally they tinkered with the amp, and connected it to a single test speaker, and THERE WAS NOISE...so the shop is basically saying its my amp, which has already been replaced once...the last thing they did that helped a lil bit leave the amp unmounted, its just resting on the plastic under my passenger seat

Basically they said fosgate's sometimes make alot of noise...

My question is, what brand or maybe what model is notorious for good noise reduction...I need atleast 65 watts x 4 RMS at 4ohm (would like more)...and I don't want to spend more than 500...

I've read the JL A4300 is really good at noise reduction, but its really weak on power...

Also, alot of people have told me 4 channel amps are notorious for producing noise in big block V6's and V8's...is that true?

Any help would be good, and don't flame me if this has been posted before, i did the best searching i could, and found alot of trouble shooting on fixing noise, but nothing on the best amp for keeping noise low...:cheers:

OH almost forgot, the noise is a soft buzz, with a whine in the background that gets higher pitched with RPM's
that is alternator noise and is due to a faulty install. you could have a v12 for all i care, no vehicle will make more noise than another.

as far as amps go, find one in your budget.

there are good installers everywhere, but i have seen some shady stuff walk out of big box stores. the most common thing that i check for if engine/alternator whine is present is a bad ground. i fixed one the other day in this kids F150. circuit installed the ground under a seat box. they also removed the 40 section of the 60/40 rear seat to install the generic box. and they installed the amps with two screws under the front seats instead of throwing them on the rear wall like they should be. and all of this should have been ran from 1/0 or two 4 gauges, instead a single 8 gauge from the battery, split by a butt connector into two 10 gauge runs to the amps. did i mention that the wrong size ring terminal was used and it wouldnt fit over the stud, so they cut it in half and tightened the nut down and sandwiched the 1/3 of the ring terminal left.
 

·
Registered
Joined
·
14 Posts
There is some great info up there, you will also want to physically check where all the grounds in the audio system are, they all need to be at the same point(headunit, processors, amp, satalite radio, etc...), and that the engine and body grounds have been upgraded as well, this can be an issue...
The A4300 power ratings are at 12V not at 14.4 like most everyone else's, so the ratings are a little under what they actually are.
Balanced cabling is another way as well to reduce induced noise, audison makes rca 2 bal adapters for there VRX series amps that you can buy. The Balanced signal is that of pro audio(live) and is very resistant to noise induction.
But 9 out of 10 times it will be install related and can be fixed without spending more money on products.
 

·
Registered
Joined
·
5,027 Posts
if you have noise before the amp, all a line driver is going to do is amplify that noise. it probably wont help. start with the basics. making sure your grounding points are solid. making sure the RCA's arent damaged or pinched.
 

·
Registered
Joined
·
205 Posts
Discussion Starter · #6 ·
SandyFJ you gave some very good points, I think what I'm going to do is re wire all the power cables to one distributer box and ground that...

BUT they said it is for sure the amp because the disconnected everything but power and hooked up one test speaker, and the second you touched the RCA stubs with anything metal it started making the noise...

Does that make since? does taht mean it is for sure the amp or could still possibly be the grounding or other issues?
 

·
Registered
Joined
·
5,027 Posts
Yeah...I can go out to my vehicle unhook the line driver and prove you wrong right now if you want. With my line driver unplugged and the amp gains turned up enough to match where the line driver was at I have FAR more background noise and a slight interference sound from what sounds like the ECU, as it is not a alternator whine. The second the line driver goes in it boosts the signal which helps throw out the ambient noise and interference, this is what ANY good line driver will do. A stronger signal is going to resist interference far better than a weaker signal. Given that, if you have an ECLIPSE headunit or the likes, you would not NEED one, as those produce a sturdy 5v signal via RCAS, where as Pioneers, Alpines, and so forth, only do around 2v max.

However, I can't say this will FIX his problem like it does mine, mine is odd, I've checked everything, did the big 3 all with 0 gauge, ran the wires correctly, did just about everything possible to remedy the problem and it was still there, I personally believe the HU (D3) is bringing the noise in. Even if I run the RCAS and tape them to the headliner and test the sound without the matrix I still have a slight interference "hiss" when the engine is on, and there ain't no way the grounds are bad.
prove me wrong if you wish. its all on your install. eclipse is garbage. i hate the one i installed in my truck. i run an alpine 9855 with a full balanced system in my FJ. you cant say anything about preamp voltages from one deck manufacturer to the next because unlike amplifier ratings, the CEA does not regulate how decks output voltages are rated. some are rms, some are peak to peak, some are just peak, but i'm sure you know that.

yes, a line driver will give you a stronger signal that is less resistant to radiated noise. but it will never improve the quality of sound. it may get louder, but louder does not make anything sound better. if you have noise to begin with at the deck or recording, now you have amplified noise.


you sound very well educated on the topic :rolleyes:, so i will save my breathe and not argue with you.

i feel like i am beating a dead horse anyway.
 

·
Registered
Joined
·
5,027 Posts
SandyFJ you gave some very good points, I think what I'm going to do is re wire all the power cables to one distributer box and ground that...

BUT they said it is for sure the amp because the disconnected everything but power and hooked up one test speaker, and the second you touched the RCA stubs with anything metal it started making the noise...

Does that make since? does taht mean it is for sure the amp or could still possibly be the grounding or other issues?
its hard to diagnose a common problem over the internet without ever seeing the vehicle.
 

·
Registered
Joined
·
5,027 Posts
Then according to you claims of Audiocontrol, Zapco, and so forth are all total B.S. Zapco uses a different cable, whoopie, still the same idea put into the design of the driver\processor itself. The line driver in my vehicle made the music far sharper and cleaner, my friends noticed it too. I have my experience with them, and you have yours, let's leave it at that. With me, it reduced ambient noise and increased sound quality by a great deal, also eliminated the need to use the amplifier gain controls and made the amp work less. Well worth the cost.
an amplifier with no processor improved the sound? hmm, not buying it. if you input floor noise into the line driver, you are going to get amplified floor noise on the way out of it. it doesnt get rid of anything, just amplifies everything thrown into it. seems as though you are a victim of advertising and the placebo effect.

and when you say your friends have noticed it too... is that supposed to make your BS claim more valid. if your friends are anything like you their word is useless as well.

please stop. you have no clue what you are talking about.
 

·
Registered
Joined
·
5,027 Posts
There is some great info up there, you will also want to physically check where all the grounds in the audio system are, they all need to be at the same point(headunit, processors, amp, satalite radio, etc...), and that the engine and body grounds have been upgraded as well, this can be an issue...
The A4300 power ratings are at 12V not at 14.4 like most everyone else's, so the ratings are a little under what they actually are.
Balanced cabling is another way as well to reduce induced noise, audison makes rca 2 bal adapters for there VRX series amps that you can buy. The Balanced signal is that of pro audio(live) and is very resistant to noise induction.
But 9 out of 10 times it will be install related and can be fixed without spending more money on products.
all ratings for amplifiers are on an even plane. CEA-2006 standards.
 

·
Registered
Joined
·
5,027 Posts
Yeah...I still think you're once again not following me in the slightest, thus your comments are making me shake my head. Let me dumb it down for you, when I take my line driver out, I have to use the GAIN knob on the amp to get the volume and voltage settings where they are supposed to be, when using the AMPLIFIER gain knob, the noise increases dramatically, at half way it's not where it's supposed to be, and the noise is very obvious.

With the line-driver, I barely have to turn the drivers knob up at all to get it PAST where the amp gains knob would have been at, thus reducing\eliminating the noise that was present when the amp gain was up to where it should be, you following yet? If not, then I give up, I can't find my way past your ego.
$20 says you are going to find yourself banned. :cheers:
 

·
Registered
Joined
·
5,027 Posts
hang on....... before you get banned:

this was taken from the processor thread. are you saying that a line driver in this form degrades the sound? seems to me like you dont know what a line driver does for the sound.

Not really worth it...some line OUTPUT converters will actually "amplify" your system via their little gain knobs...but in my opinon they degrade sound, a Line DRIVER isn't really made for a stock system. Save up for a new HU, heck if I was you I'd shell out the $ right now (even if I didn't have it) because the Pionner D3's are DIRT cheap right now and they are a killer headunit. And in about a month, they will all be gone, and be replaced by Pionner F-Series of "Flash memory" head units...bleh.
 

·
Registered
Joined
·
14 Posts
all ratings for amplifiers are on an even plane. CEA-2006 standards.
Well, you will see some new model #'s this year from JL to more reflect the power at 14.4.. I know about the standards, but this is how lesser amps make them selves look bigger and the 12v vs 14.4v is not included in this standards system(this is from the horses mouth @ JL), now keep in mind that i am not going to continue on this, i am a JL dealer up here, and was just at the JL factory last month. It's the info i was given.
 

·
Registered
Joined
·
5,027 Posts
Well, you will see some new model #'s this year from JL to more reflect the power at 14.4.. I know about the standards, but this is how lesser amps make them selves look bigger and the 12v vs 14.4v is not included in this standards system(this is from the horses mouth @ JL), now keep in mind that i am not going to continue on this, i am a JL dealer up here, and was just at the JL factory last month. It's the info i was given.
just because they give out more information than required doesnt mean the amplifier isnt rated on an even plane. when the ratings are published in CA&E every year, it is all rated the same way.

i'm sure they dont tell you the deep secrets of what the slash series do at lower ohms. but that is either here nor there.

which JL location did you go to?

you can throw around where you have been before, but some of these people have tried to hire me when living in arizona. i still keep in touch with the presidents and owners of some companies.
 

·
Registered
Joined
·
14 Posts
I wasn't trying to start anything here, i didn't explain what i meant properly(i'm a slow typer), it's a consumer POV thing, i know they are all rated the same, but this isn't our thread so very quick...
I don't disagree with what you said about ratings, yeah we learned some neat secrets, Miramar, FL, Andy is such a nice guy its unbelievable!
 

·
Premium Member
Joined
·
1,762 Posts
OK this is what I've had since last year...

Pioneer AVH-P6800
Fosgate punch 500 amp for sub
Fosgate punch 12" P2 in Q-logic box
Fosgate p450.4 4 channel amp
Components in the front, infiniti 3" in the rear

I've had noise since all that was put in, I went back and forth to circuit city 5 times, they made sure there was no ground loops, they moved the amp around, changed the grounds, re-ran the power wires farther from the RCA's...I sent the amp back and crutchfield sent me a brand new one, STILL NOISE...finally circuit city put RCA filters on, and it helped but I still had noise and just got used to it...

Recently I replaced the AVH-p6800 wit a Kenwood DNX 8120, and the Q logic box with the wicked cas box. I had the best local shop re-wire the 4 channel amp, they did a quality job (they work one imports, luxery cars, and do alot of custom work)...after two seperate times of trouble shooting there was still noise...I checked everything my self and the power wires are run separately, the ground is short, the noise filters are still on the RCA's (they even put on newer higher quality ones)...and there IS STILL NOISE... Finally they tinkered with the amp, and connected it to a single test speaker, and THERE WAS NOISE...so the shop is basically saying its my amp, which has already been replaced once...the last thing they did that helped a lil bit leave the amp unmounted, its just resting on the plastic under my passenger seat

Basically they said fosgate's sometimes make alot of noise...

My question is, what brand or maybe what model is notorious for good noise reduction...I need atleast 65 watts x 4 RMS at 4ohm (would like more)...and I don't want to spend more than 500...

I've read the JL A4300 is really good at noise reduction, but its really weak on power...

Also, alot of people have told me 4 channel amps are notorious for producing noise in big block V6's and V8's...is that true?

Any help would be good, and don't flame me if this has been posted before, i did the best searching i could, and found alot of trouble shooting on fixing noise, but nothing on the best amp for keeping noise low...:cheers:

OH almost forgot, the noise is a soft buzz, with a whine in the background that gets higher pitched with RPM's
SandyFJ you gave some very good points, I think what I'm going to do is re wire all the power cables to one distributer box and ground that...

BUT they said it is for sure the amp because the disconnected everything but power and hooked up one test speaker, and the second you touched the RCA stubs with anything metal it started making the noise...

Does that make since? does taht mean it is for sure the amp or could still possibly be the grounding or other issues?

Hakim, where is it grounded? where is the amps grounded on the truck? True it is hard to say or help unless we can see your setup. It might contradict theories about setting up a sound system in a vehicle but try running the ground straight to the battery and see what happens.

If you use a big gauge wire from the battery positive to the amp/dist. block, and you ground the amp to the nearest clean metal there is with the same gauge wire, chances are is that the body of the truck isn't using the same gauge ground wire to the batt. and alternator ground. Try doing the "Big Three." and see if that helps.
 

·
Registered
Joined
·
5,027 Posts
I wasn't trying to start anything here, i didn't explain what i meant properly(i'm a slow typer), it's a consumer POV thing, i know they are all rated the same, but this isn't our thread so very quick...
I don't disagree with what you said about ratings, yeah we learned some neat secrets, Miramar, FL, Andy is such a nice guy its unbelievable!
i wouldnt call them neat by any means. i would call them lame if i had to throw a term at it.
 

·
Registered
Joined
·
205 Posts
Discussion Starter · #19 ·
OK, so to update everyone I stupidly took the installer advice, got rid of the supposed bad amp and bought a JL audio 600/4v2 (the amp with the highest signal to noise reduction in cruthfields catalogue that was under 600).

I put in the new amp my self using the old wiring and what do you know, the NOISE GOT WORSE.

I put in the new amp my self so I could answer some questions about the install.

The ground is bolted directly to the metal between the passenger seat and the door jam....under that plastic panel that pops out...he didn't sand away the paint...so fixing the ground is my first mission

The power wire is run around the back of the front seats to the left side of the vehicle then to the front and the battery, the RCA's and speaker wires are run directly from the passenger side to the front along the door jam and up to the deck. So in other words the rca's and power wires never come close to each other until they reach the amp. The RCA's and speaker wires are run together.

I am starting easy and working my way up, first I bought a JL audio ground bolt, I'm going to dremmel some paint away, and use the bolt to ground the deck and the 4 channel amp in the same spot (so I know for sure there is no ground loop)

Three questions I have are:

1) should I ground my sub amp to the same spot at the ground bolt or leave it the way it is?
2) is it ok that the RCA's are run with the speaker wire on the way back to the deck?
3) I believe what the installer did was run new speaker wire back to deck and spliced it with the old factory wire, instead of running new speaker wire to each speaker...could this be a problem?

Any help and comments would be appreciated, this noise is driving me insane...
 

·
Registered
Joined
·
14 Posts
1) Yes, this is to just further eliminate the ground loop potential issue.
2) Yes, this shouldn't be a problem.
3) If you don't like cheese, then it's a problem, but not a real problem for what you are looking for, you might want to rerun those to the speakers...
Also, i would suggest upgrading your engine and body grounds in the truck, and when you ground your deck to the back, twist the ground and the remote on together, this will provide some noise resistance on the remote line...
Maybe some pics might help some of us to help you.
 
1 - 20 of 20 Posts
Top