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Aric'sX15
06-30-2011, 02:28 AM
When the key is in accessory, there's no hiss
But when the boat is on, there's That hiss. I called my local dealer, they suggested putting in a RCA ground loop. That didn't work. Its getting frustrating, ive checked all connections and any other thing I could think of. My set up is the stock JL 6 channel for the in boats and sub, and an Alpine pdx 600 watt for the 4 tower speakers. Anny help??

swatguy
06-30-2011, 05:22 AM
Sounds like ground issue for sure. Is your head unit grounded directly to battery? I had similar problem. My local shop told me to run the ground from my head unit this way. Problem solved. Electrical stuff is the worst. Have to try every little thing

1redTA
06-30-2011, 06:13 AM
http://www.termpro.com/articles/noise.html

nice article for car audio

JimN
06-30-2011, 06:15 AM
When the key is in accessory, there's no hiss
But when the boat is on, there's That hiss. I called my local dealer, they suggested putting in a RCA ground loop. That didn't work. Its getting frustrating, ive checked all connections and any other thing I could think of. My set up is the stock JL 6 channel for the in boats and sub, and an Alpine pdx 600 watt for the 4 tower speakers. Anny help??

If the sound rises and falls with the engine RPM, it can be a grounding issue but it can also be due to the amps' input sensitivity set incorrectly. JL has info on their site for doing this and it's the best method I have seen, other than using an oscilloscope (which they used when they developed it).

FYI- by telling you to "put in an RCA ground loop", they proved that they don't understand what a ground loop is. It's not something you put in, it's something that needs to be avoided.

A ground loop is caused by resistance on the power and/or ground wires when multiple paths to ground exist. Who installed the Alpine head unit? If they grounded it to the main harness, that could be the cause. The best practice is to run a 12ga ground wire from the amplifier's ground terminal to the head unit and install a ring terminal on the end of the wire. The threaded stud that comes with the head unit should be used to hold the support strap in place and will accept the new ground wire as well as the head unit's ground wire. This usually eliminates the noise.

Look at the input level controls (which I called 'input sensitivity controls')- if they're turned up fully, do the setup I mentioned before anything else. If you don't, your speakers won't live long- when these controls are turned up all the way, the amp will distort before you reach full volume on the head unit and the distortion causes all kinds of problems for speakers. The tweeters will be the first to go.

bturner2
06-30-2011, 07:14 AM
Sad to say but I've found most wiring in boats to be lacking in attention to detail especially if a car audio shop or previous owner has had their hands on it. It would appear this is so because of the cost to do things right. To a large degree most people are more interested in getting cheap than right.

The easiest way to clean up your power and grounding circuits is to install distribution blocks for both power and grounding circuits. This will ensure that all the amps are getting adequate power through large enough cables and that all the grounds are coming to and tied to the same power/grounding source which should be your battery.

Sonic Electroix carries a large assortment of distribution blocks from Streetwires which I have used and have found to be a high quality product. I'm sure there are several other products out there that would do the job just as well but these are the ones that I've used......

http://www.sonicelectronix.com/cat_m230_i205_streetwires-power-distribution-blocks.html

You'll also want to be sure the cables supplying power and ground are sized correctly as well. This is one of those areas where larger is actually better. I found Genuine Dealz to be about the best place to get marine quality wire and connectors.

http://genuinedealz.com/

Cleaning up your installation with these components will not be cheap but if you do a little research and take your time it will be done right and will clear up a lot of problems going forward.

davidstan
06-30-2011, 07:29 AM
i have the same issue except i hear no hiss until i trigger it by flipping a switch like anc lights, blower, PP etc. i can manipulate the hiss with the throttle so with me it is a grounding issue but for the life of me i can not cure it. looks like i will be deinstalling and reinstalling with new cable.

agarabaghi
06-30-2011, 07:46 AM
this is an rca ground loop...

http://www.amazon.com/B25N-MOBILE-GROUND-ISOLTRNOICE-FILTER/dp/B000LP4RMG

mseller
06-30-2011, 08:51 AM
is the hissing coming from all the speakers? mine is just coming from my tower speakers

JimN
06-30-2011, 09:53 AM
i have the same issue except i hear no hiss until i trigger it by flipping a switch like anc lights, blower, PP etc. i can manipulate the hiss with the throttle so with me it is a grounding issue but for the life of me i can not cure it. looks like i will be deinstalling and reinstalling with new cable.

Clicks and pops are often bad grounding, too. Try connecting the audio shield to ground- you can strip the insulation from a piece of wire and wrap the bare wire around the RCA plug shield and then do the same to the other end of the wire, but connect it to the amplifier's ground wire. If it stops the noise, solder the wire to the audio shield and run the new ground wire to the amp, securing it along the way.

This can work for whine, too.

JimN
06-30-2011, 09:56 AM
this is an rca ground loop...

http://www.amazon.com/B25N-MOBILE-GROUND-ISOLTRNOICE-FILTER/dp/B000LP4RMG

It's a ground loop filter- there's a difference. I know what they were referring to. Unfortunately, that type of filter can alter the sound in a bad way- it's always best to take care of the basics instead of adding anything in the audio path. If one of these filters is added and the bass is reduced, it would be far better to run the new ground wire.

JimN
06-30-2011, 09:57 AM
is the hissing coming from all the speakers? mine is just coming from my tower speakers

Then, make sure the input controls are set correctly. Speakers don't hiss- that comes from too much gain, either from an amplifier or equalizer.

Mgboyd25
06-30-2011, 10:19 AM
You have my attention just installed new tower speakers and have the same problem.

mseller
06-30-2011, 11:02 AM
Then, make sure the input controls are set correctly. Speakers don't hiss- that comes from too much gain, either from an amplifier or equalizer.

noted. however, this is just at low volume...they sound great when riding...

Aric'sX15
06-30-2011, 03:30 PM
Sad to say but I've found most wiring in boats to be lacking in attention to detail especially if a car audio shop or previous owner has had their hands on it. It would appear this is so because of the cost to do things right. To a large degree most people are more interested in getting cheap than right.

The easiest way to clean up your power and grounding circuits is to install distribution blocks for both power and grounding circuits. This will ensure that all the amps are getting adequate power through large enough cables and that all the grounds are coming to and tied to the same power/grounding source which should be your battery.

Sonic Electroix carries a large assortment of distribution blocks from Streetwires which I have used and have found to be a high quality product. I'm sure there are several other products out there that would do the job just as well but these are the ones that I've used......

http://www.sonicelectronix.com/cat_m230_i205_streetwires-power-distribution-blocks.html

You'll also want to be sure the cables supplying power and ground are sized correctly as well. This is one of those areas where larger is actually better. I found Genuine Dealz to be about the best place to get marine quality wire and connectors.

http://genuinedealz.com/

Cleaning up your installation with these components will not be cheap but if you do a little research and take your time it will be done right and will clear up a lot of problems going forward.

well the boat is only a year old, and i havent touched the wiring in it. We bought the boat new, and it has only gotten worse now that ive put a bigger amplifier to the tower speakers.

Aric'sX15
06-30-2011, 03:31 PM
is the hissing coming from all the speakers? mine is just coming from my tower speakers

mine comes from all speakers.

Aric'sX15
06-30-2011, 03:34 PM
If the sound rises and falls with the engine RPM, it can be a grounding issue but it can also be due to the amps' input sensitivity set incorrectly. JL has info on their site for doing this and it's the best method I have seen, other than using an oscilloscope (which they used when they developed it).

FYI- by telling you to "put in an RCA ground loop", they proved that they don't understand what a ground loop is. It's not something you put in, it's something that needs to be avoided.

A ground loop is caused by resistance on the power and/or ground wires when multiple paths to ground exist. Who installed the Alpine head unit? If they grounded it to the main harness, that could be the cause. The best practice is to run a 12ga ground wire from the amplifier's ground terminal to the head unit and install a ring terminal on the end of the wire. The threaded stud that comes with the head unit should be used to hold the support strap in place and will accept the new ground wire as well as the head unit's ground wire. This usually eliminates the noise.

Look at the input level controls (which I called 'input sensitivity controls')- if they're turned up fully, do the setup I mentioned before anything else. If you don't, your speakers won't live long- when these controls are turned up all the way, the amp will distort before you reach full volume on the head unit and the distortion causes all kinds of problems for speakers. The tweeters will be the first to go.

I installed the alpine amp. it was only a matter of switching wires though, im running the stock clarion unit that was factory installed.

swatguy
06-30-2011, 03:46 PM
Even just swapping the amp can cause this. I would assume the amp u put in has more wattage than the stock clarion. The factory grounds the head unit to a "common" ground. When I upped my wattage, went with Hlcd speaker, and upgraded my amp my boats towers also started hum. Undid the factory head unit "common" ground and ran it to my distribution block for my two amps like the above mentioned and problem solved. I am running a clarion m475 which is an upgrade from the original factory with regards to features, but essentially same specs as original.

JimN
06-30-2011, 03:51 PM
well the boat is only a year old, and i havent touched the wiring in it. We bought the boat new, and it has only gotten worse now that ive put a bigger amplifier to the tower speakers.

OK, so you put a bigger amp in- how much more power and what are the power supply requirements for the new amp? It's possible that the new amp needs heavier power cable and the input level controls need to be set properly, as I posted before. Wide open DOES NOT give you full power output, it gives you distortion and noise. They're variable because the output signal isn't the same for all head units.

JimN
06-30-2011, 03:56 PM
I installed the alpine amp. it was only a matter of switching wires though, im running the stock clarion unit that was factory installed.

Power and ground connections are the most important in any circuit. You can't have any appreciable resistance on either if you want the system to work flawlessly and if resistance can be measured, the power supply voltage will drop. This voltage drop is what causes a ground loop- the amp doesn't care where it gets its ground from, it just wants a certain voltage, so it causes DC voltage to pass along the audio cables. This is a classic ground loop- the easy way to test for it is to disconnect the audio cables and listen for the noise. If it's gone after unplugging the cables, measure for DC voltage between the shield of the head unit's RCA output plug and the shield for the amp's input jack. If you can measure voltage, you'll always have noise.

Aric'sX15
06-30-2011, 04:35 PM
when you unplug the rca's, the noise is gone.

J NORRIS
06-30-2011, 04:42 PM
JimN, could it be that the rca cables are ran too close to the power supply cables? Causing the whining noise. If you rev the motor, does the whine go up and down with the motor?

Aric'sX15
06-30-2011, 04:44 PM
yeah, when i rev the engine it goes up and down with the revs.

J NORRIS
06-30-2011, 04:53 PM
Are your rca cables right next to the power supply wire/cable? If so seperate them and see if this helps, it should. They should be as far apart as possible, not ran side by side.

Aric'sX15
06-30-2011, 04:54 PM
there not close. its all factory ran wires, so im not sure how everything is ran.

J NORRIS
06-30-2011, 05:24 PM
I don't know what you have tried so far, JimN is going to be the one who has the technical knowledge to help you out. If you used the same wires, they may need to be a bigger gauge.
Everytime I have come across that whining noise, 9 times out of 10 it was cables ran too close together. People try to run all the wires on one side of the car/truck.

Aric'sX15
06-30-2011, 06:20 PM
its not that, i just tested that.

atlfootr
06-30-2011, 09:45 PM
Sounds like ground issue for sure. First thing I said, when I read your symptoms.

Ground issue!

Aric'sX15
07-01-2011, 01:41 AM
I'm gonna either fix it tomorrow, or Texas Mastercraft said they'd fix
It for me. Just depending on if I want to waste 50 bucks in gas going there.

Ric
07-01-2011, 05:00 PM
I found something on wakeworld about a relay for the radio power.

First thing I did to isolate that hissing is to do what others said above.. Ground the head unit directly to the battery. (Do that to the amps too if they aren't already)

You can cheat and ground your head unit to a nearby amp if the amp ground line runs directly to the battery... (It'll save you a wire run)

brucemac
07-01-2011, 06:13 PM
as already noted by many, my money's on a ground issue. make sure ALL stereo equipment shares a common ground.

JimN
07-02-2011, 05:23 PM
We need to define some things-

Hiss is the kind of noise you would hear from a blank tape being played on a tape deck or the noise between stations on the radio. It's usually caused by noisy electronics, an equalizer that has the high frequency bands set too high (way above the zero line) or level controls on an amplifier that are set too high.

Hum has a specific frequency, although that can increase or decrease in pitch. Hum is lower frequency, not a squeal. The only causes of hum I have heard, that was one frequency in a 12VDC audio system, were A) touching the pin of an RCA plug with a finger (and it's a rare case when you would get a hum that was more than barely audible) and B), DC voltage going to the input of an amp or equalizer.

Whine is what comes through an audio system, usually because of inadequate cable gauge, audio cables run next to power cables, power wires throwing ioff EMI (Electro-Magnetic Interference) and being picked up by a badly shielded audio cable, tape head or other wiring that may be susceptible. It can also come from a bad bridge rectifier or filter in/on an alternator and the frequency & pitch (musical note) of the whine increases with RPM.

Oscillation is a squeal that can't be eliminated by anything other than shutting the system off. It's usually caused by bad internal components or improper speaker loads presented to an amplifier.

Now, which type of noise is the cause of this thread? Hiss DOES NOT come from bad grounds.

Aric'sX15
07-03-2011, 11:58 AM
It's a whine. I moved the ground from the factory grounding point to one of the batteries. That didnt work.

Aric'sX15
07-03-2011, 08:10 PM
Tried just about everything. Going to try using a separate battery for the amps and head unit.

Stutsman230
07-03-2011, 10:09 PM
Did you say that this has always been a problem? If it just started showing up there may have been a small order of grounds problem and as connections get corroded the voltage drop is getting bigger as others on this forum have stated.


The whine is probably caused by the "order of grounds" not the gauge of the wire. The ground wiring in order of connections should be as follows:

Motor wiring ground connects closest to the battery,
Next I would connect the gauges and any other motor system grounds,
Next are the power amps and finally the audio equipment such as head unit, radio, equalizer.

The basic idea is that you don't want any noisy grounds such as ignition or alternator to send current pulses through the most sensitive circuits. The reason for the amps to go before the head unit or radio is that the high amplifier current will modulate the sensitive circuit preamps etc and either create oscillation or distortion.

Always connect the highest current devices (least sensitive to noise) closer to the battery and the most sensitive farthest away from the battery. Replacing the wiring with welding cable will not fix a ground loop problem.

JimN
07-03-2011, 10:49 PM
It's a whine. I moved the ground from the factory grounding point to one of the batteries. That didnt work.

If the 4 studs are on a metal strap, it's called a ground buss and it eliminates the need to run a separate ground wire for each circuit to the battery post- it makes a cleaner installation, but the main ground cable needs to be able to handle the current, or its resistance will increase under load and cause voltage drop, which manifests itself as noise when you're dealing with an audio system.

Re-read the part in my post about looping the head unit's ground wire to the stud in the case that SHOULD be used for the back strap, then run a ground wire to the amplifier's negative terminal. If there's no room on the terminal, use a distribution block and locate it at the amp. This works for about 90% of the noise problems I dealt with in more than 20 years of working with 12V electrical systems. If it's a radiated noise problem, it's usually because the audio cables are bundled with power leads, usually along the driver's side of the boat or going from the driver's side to the amplifier when it's on the passenger side.

Did you touch a grounded wire to the RCA shield, yet? By 'grounded', I mean grounded to the amplifier's ground terminal, not the dash ground.

Aric'sX15
07-04-2011, 12:13 AM
I grounded the head unit to the backstrap, and that didn't work. I'm going to relocate all wires to where they aren't touching any others, and adding a third battery that's dedicated to the stereo. If that doesn't work I'm gonna be pissed for one, and send it to the dealer.

JimN
07-04-2011, 12:25 AM
I grounded the head unit to the backstrap, and that didn't work. I'm going to relocate all wires to where they aren't touching any others, and adding a third battery that's dedicated to the stereo. If that doesn't work I'm gonna be pissed for one, and send it to the dealer.

Grounding the head unit's wire to the back strap is only half of the point- a new ground wire needs to be run from the amplifier to the head unit.

The point of all of this it so make sure there's no difference in resistance when you measure from the battery negative to the head unit and to the amplifier. This causes DC voltage to flow between the amp and head unit (remember my comment about the amp needing a better ground and not caring where it gets it?) and this is exactly what causes the noise- you don't want DC current flowing on the audio cables. If you have ever seen someone refer to 'star grounding', this is what we need to achieve. 'Star grounding' isn't a physical thing, like using one stud to use as a common ground point but it's not a bad way to do it. It's more of an electrical issue- it's possible to use one ground point and still have noise problems because of the different wire lengths from the ground to the various devices.

You shouldn't need a third battery and adding another one can actually cause more problems because the differences caused by resistance can stack up and make things even worse. Keep it simple.

If you have extra power wire, completely disconnect the head unit from the dash harness. Put a spade lug on a piece of black 14ga wire and connect it from the amp's ground terminal. Then, take a red 14ga wire, install a spade lug and connect it to the head unit's main power wires (the battery wire is yellow and the switched wire is red). If you have a distribution block for positive and ground (with multiple amps, I would highly recommend this), make the connections to the head unit there, not directly to the amplifier's terminals. Your noise should be gone and if it is, you'll want to run the new power wire to the head unit's location and add a relay for the red lead. This relay will be triggered by the original stereo wiring harness and I'll post a diagram if you need one. You'll also need to add a fuse at the power distribution block for the new head unit wire.

TallRedRider
07-04-2011, 01:36 PM
Grounding the head unit's wire to the back strap is only half of the point- a new ground wire needs to be run from the amplifier to the head unit.

The point of all of this it so make sure there's no difference in resistance when you measure from the battery negative to the head unit and to the amplifier. This causes DC voltage to flow between the amp and head unit (remember my comment about the amp needing a better ground and not caring where it gets it?) and this is exactly what causes the noise- you don't want DC current flowing on the audio cables. If you have ever seen someone refer to 'star grounding', this is what we need to achieve. 'Star grounding' isn't a physical thing, like using one stud to use as a common ground point but it's not a bad way to do it. It's more of an electrical issue- it's possible to use one ground point and still have noise problems because of the different wire lengths from the ground to the various devices.

You shouldn't need a third battery and adding another one can actually cause more problems because the differences caused by resistance can stack up and make things even worse. Keep it simple.

If you have extra power wire, completely disconnect the head unit from the dash harness. Put a spade lug on a piece of black 14ga wire and connect it from the amp's ground terminal. Then, take a red 14ga wire, install a spade lug and connect it to the head unit's main power wires (the battery wire is yellow and the switched wire is red). If you have a distribution block for positive and ground (with multiple amps, I would highly recommend this), make the connections to the head unit there, not directly to the amplifier's terminals. Your noise should be gone and if it is, you'll want to run the new power wire to the head unit's location and add a relay for the red lead. This relay will be triggered by the original stereo wiring harness and I'll post a diagram if you need one. You'll also need to add a fuse at the power distribution block for the new head unit wire.

I think that is good advice right there. I learned to do it this way from these forums (thanks to guys like JimN), and have never seen the problems that I often hear of others having.

JimN
07-04-2011, 06:31 PM
I think that is good advice right there. I learned to do it this way from these forums (thanks to guys like JimN), and have never seen the problems that I often hear of others having.

I learned to do this because it was my job- I went to CES and other mobile electronic training seminars, read everything I could find (which, back in the late '70s-mid-'80s, was not as easy as it is now) and discussed it with other installers I knew. The recommendations of:
1) Do everything that is recommended by the experts of the time, by the book
2) Do what is mentioned but not necessarily known to be effective
3) get the sticks & beads and hope it works

I can't tell how many noise problems I fixed but many of them were from adding equipment to cabling that was at the edge of adequate. Adding a few amperes of current draw makes all the difference when a power cable is rated for 50A and the extra draw causes the voltage to drop only 1VDC. That volt on the audio cables doesn't go away unless the grounding and power supply are close to perfect.

davidstan
07-05-2011, 02:07 PM
"Grounding the head unit's wire to the back strap is only half of the point- a new ground wire needs to be run from the amplifier to the head unit." JimN

Jim, I have one amp working great (the smaller tower amp) but the larger amp will whine like a 3 yr old. Does this mean the head unit is fine and that i need to just ground the amp to the head? I already traced one ground in the amp power cable to the ground strip in the aft. Is it kosher to ground the amp in 2 spots and what does the ground terminal look like on the clarion units? Should i just run another ground cable from the amp to the ground strip? Sorry for all the questions but this noise has driven me insane. Thx for all the troubleshooting help.

Aric'sX15
07-05-2011, 03:10 PM
Grounding the head unit's wire to the back strap is only half of the point- a new ground wire needs to be run from the amplifier to the head unit.

The point of all of this it so make sure there's no difference in resistance when you measure from the battery negative to the head unit and to the amplifier. This causes DC voltage to flow between the amp and head unit (remember my comment about the amp needing a better ground and not caring where it gets it?) and this is exactly what causes the noise- you don't want DC current flowing on the audio cables. If you have ever seen someone refer to 'star grounding', this is what we need to achieve. 'Star grounding' isn't a physical thing, like using one stud to use as a common ground point but it's not a bad way to do it. It's more of an electrical issue- it's possible to use one ground point and still have noise problems because of the different wire lengths from the ground to the various devices.

You shouldn't need a third battery and adding another one can actually cause more problems because the differences caused by resistance can stack up and make things even worse. Keep it simple.

If you have extra power wire, completely disconnect the head unit from the dash harness. Put a spade lug on a piece of black 14ga wire and connect it from the amp's ground terminal. Then, take a red 14ga wire, install a spade lug and connect it to the head unit's main power wires (the battery wire is yellow and the switched wire is red). If you have a distribution block for positive and ground (with multiple amps, I would highly recommend this), make the connections to the head unit there, not directly to the amplifier's terminals. Your noise should be gone and if it is, you'll want to run the new power wire to the head unit's location and add a relay for the red lead. This relay will be triggered by the original stereo wiring harness and I'll post a diagram if you need one. You'll also need to add a fuse at the power distribution block for the new head unit wire.
I'd really appreciate a diagram! thanks for all the help!!

Aric'sX15
07-05-2011, 04:56 PM
I have tried all of the things you have suggested with my Electrical engineer neighbor, and I'm still SOL here. Any other suggestions?

davidstan
07-05-2011, 07:58 PM
http://www.termpro.com/articles/noise.html

nice article for car audio

This is a good article for our problem. Printed it and will use this weekend in my 7 week old troubleshoot of the pos system I have. I am not qualified to do this but I am going to rip the whole amp out and reinstall with new wire/cable/ground and see if I stumble on an answer because nothing else has worked.

JimN
07-05-2011, 08:24 PM
"Grounding the head unit's wire to the back strap is only half of the point- a new ground wire needs to be run from the amplifier to the head unit." JimN

Jim, I have one amp working great (the smaller tower amp) but the larger amp will whine like a 3 yr old. Does this mean the head unit is fine and that i need to just ground the amp to the head? I already traced one ground in the amp power cable to the ground strip in the aft. Is it kosher to ground the amp in 2 spots and what does the ground terminal look like on the clarion units? Should i just run another ground cable from the amp to the ground strip? Sorry for all the questions but this noise has driven me insane. Thx for all the troubleshooting help.

It's impossible without seeing a diagram with dimensions, wire gauges, actually seeing the terminals and the wire routing. I can make educated guesses, but if you can post some clear photos, it would be a lot easier.

No, you don't want to ground the amp in two spots but if you have a common ground point, it's a good idea to ground the whole audio system to that. I would strongly consider the comments about not using the dash ground if the system has an amplifier, or more.

Thrall
07-05-2011, 08:41 PM
This is a good article for our problem. Printed it and will use this weekend in my 7 week old troubleshoot of the pos system I have. I am not qualified to do this but I am going to rip the whole amp out and reinstall with new wire/cable/ground and see if I stumble on an answer because nothing else has worked.

It's frustrating to trace a grounding problem, but I can tell you what did work although I never traced my problem since I was doing a complete re-intall of the amps/wiring anyway.
I ran a dedicated 2ga ground to the engine block and to a dist block near the amps. All of the amps and stereo are grounded to that dist block. The rest of the boat loads (dash/guages, ballast, etc) are grounded with another dedicated 2ga ground to the engine and a dist block near the batteries.
A bad RCA cable can cause the same problem. check by swapping cables and see if the bad sound follows the RCA cable. Also try hooking a ground wire from the head unit case to the same ground as the amps.
If it's just one speaker but there are multiple spkrs off of the same channel then look into that speaker.
Those are the 3 most likely areas and I'd start with the easiest, gnd head unit and ck RCA cables first.
Then ck speaker(s), then re-wire with good solid dedicated grounds.

JimN
07-05-2011, 08:42 PM
I'd really appreciate a diagram! thanks for all the help!!

Here's a good one- this site has a ton of good information-
http://www.the12volt.com/relays/relays.asp

Connect tab 85 to the original radio red power lead (on with ignition or a dash switch). Connect tab 86 to the old radio ground. Connect tab 30 AND THE RADIO'S YELLOW POWER WIRE to the new power wire coming from the power distribution block and tab 86 to the radio's red power wire. The new ground wire that goes to the ground distribution block should have a ring terminal crimped and soldered to the end and this should be attached to the stud on the back of the radio, along with the radio's ground wire.

This whole thing is to guarantee that the amplifier and radio connect to power and ground at the same point, electrically

If you remember science classes, they taught that there are two kinds of energy- kinetic and potential. Potential energy is any kind of energy that can be stored in one form, or another. Voltage is potential energy and if you ever see someone refer to a 'difference in potential' or maybe 'potential difference', they're referring to voltage. Positive and negative connections used for power going to different parts of an audio system will always show resistance between them unless they're incredibly close together physically, or as I mentioned before, electrically. Proximity is a great way to cut down on the chances of this resistance and therefore, noise.

Just because it's possible, I would start by using a different set of audio cables and route them away from where the existing ones are. If the noise goes away, it could be a radiated noise issue. If that's really how it's getting into the system, re-routing is about the only way you'll be able to eliminate the noise because shielding electromagnetic interference is very difficult, so distance is your best friend with this.

krutzmart
07-06-2011, 09:28 AM
Try to keep the RCA wires as far away from anything that has power draw like, power pos. & neg. to your amp, like lighting wire,battery cables, anything that has a power draw can disturb your sound through your RCA cable.
Bad Shielding on you RCA ? Spend the money and buy the good RCA's. It's worth it to have the better shielding to just this reason.

Ipod cable conection is the same thing. If you have your Ipod hookup connected to the back of your sorce unit and it is sitting on top of you amp's. Just being to close to your amps could cause that distotion. MOVE IT AWAY FROM POWER LINES/and or sorce's.

JimN
07-06-2011, 09:40 AM
I forgot to add- if the audio cables must cross power wires, do it at a right angle, or as close to it as possible. It's much less likely for the noise to transfer from one to the other this way.

krutzmart
07-06-2011, 11:50 AM
Thats a great point to point out.
Never run RCA's parrallel next to or with power wires.

davidstan
07-07-2011, 03:09 PM
So the amp should be grounded to the same post as the rest of the system. I guess it would be appropriate then to disconnect the existing ground cable and run a 12 gauge wire from the amp to the head unit? Dont want to blow up my system and there is no one anywhere close to me that would be considered an expert on this type stuff.

JimN
07-07-2011, 03:33 PM
So the amp should be grounded to the same post as the rest of the system. I guess it would be appropriate then to disconnect the existing ground cable and run a 12 gauge wire from the amp to the head unit? Dont want to blow up my system and there is no one anywhere close to me that would be considered an expert on this type stuff.

Yes, sort of but it's best to look at the system's power connections from the battery toward the equipment. The + distribution block comes after the battery + post, then the amp and anything else takes its + power from the same place. The ground connections should be made the same way.

No, don't connect a 12ga wire from the amp to the head unit and use that as your ground. What you need to do is what I posted before- disconnect the head unit's ground wire from the dash ground wire, loop it (the ground wire in the head unit's harness) back to the stud on the rear of the head unit and run the 12ga from the head unit's stud to the amp's ground point. If you were to ground the amp to the head unit, the amp may not even turn on and if it did, it wouldn't last long because a 12ga wire will never handle the current the amp will demand- teh dash harness's ground wire is even thinner.

Aric'sX15
07-10-2011, 12:52 PM
I re ran my RCA's away from any power wires, and I still got the engine noise. I grounded both amps and head units differently, and it didn't work.
So I'm borrowing a wetsounds EQ from a neighbor and seeing if eliminating the head unit works.

JimN
07-10-2011, 01:03 PM
I re ran my RCA's away from any power wires, and I still got the engine noise. I grounded both amps and head units differently, and it didn't work.
So I'm borrowing a wetsounds EQ from a neighbor and seeing if eliminating the head unit works.

Am I correct in thinking that your system consists of a head unit and two amplifiers? If that's correct, the noise should have been eliminated as long as you grounded the head unit to the same point as the amps and your power cables are sufficient. Did you replace the power wires with one wire and a relay, as I mentioned?

By 'eliminate the head unit", would you do this so you can use an iPod as your source? If so, you may have the same problem but it's not an absolute.

davidstan
07-10-2011, 05:48 PM
More trouble shooting this wknd. I tried disconnecting all speaker cables from the problem amp and heard no hiss or whine and my good amp still was clear. So I went to the ground buss in the rear and noticed one amp is grounded to the same bolt as the system and another amp on another bolt. Thinking one is a good ground the other not so I switched...no soap. Same damn staticky hiss whine as always. Pretty sure it is in my cables to the bad amp or a bad amp since I have one amp not giving me a problem at all. Closest JL dealer is in Lagrange :( so I keep trying different angles. Btw input sens adjustment helped only in decreasing ALL sound from the affected speakers.

JimN
07-10-2011, 08:51 PM
More trouble shooting this wknd. I tried disconnecting all speaker cables from the problem amp and heard no hiss or whine and my good amp still was clear. So I went to the ground buss in the rear and noticed one amp is grounded to the same bolt as the system and another amp on another bolt. Thinking one is a good ground the other not so I switched...no soap. Same damn staticky hiss whine as always. Pretty sure it is in my cables to the bad amp or a bad amp since I have one amp not giving me a problem at all. Closest JL dealer is in Lagrange :( so I keep trying different angles. Btw input sens adjustment helped only in decreasing ALL sound from the affected speakers.

So, your amps are grounded to a bolt somewhere and a cable connects that to the battery? I posted it before in bold print and I'll do it again- ALL POWER AND GROUNDS REFERENCE TO THE BATTERY POSTS. You can use a distribution block to make it a clean installation but from there, the positive and negatives go to the battery posts with an adequately sized cable. How high are the input level controls set? There's a right and a wrong way to set them and the head unit's output determines where they should be set.

Post photos of the amp's input jacks and level controls, the ground point, all makes and models of teh equipment and any connections you or anyone else made for the audio system.

Aric'sX15
07-11-2011, 02:15 PM
Am I correct in thinking that your system consists of a head unit and two amplifiers? If that's correct, the noise should have been eliminated as long as you grounded the head unit to the same point as the amps and your power cables are sufficient. Did you replace the power wires with one wire and a relay, as I mentioned?

By 'eliminate the head unit", would you do this so you can use an iPod as your source? If so, you may have the same problem but it's not an absolute.

I replaced all wires as you suggested. You're correct about the two amps and head unit. I'm just going to try the wetsounds EQ, and if that doesn't work I'm going to take it to a stereo shop.

JimN
07-11-2011, 02:57 PM
I replaced all wires as you suggested. You're correct about the two amps and head unit. I'm just going to try the wetsounds EQ, and if that doesn't work I'm going to take it to a stereo shop.

Make sure the installers at the shop are well trained. Read the link for info on where to find a certified shop, what kinds of questions to ask, etc. If you don't see ant certificates on the wall and they look at you like you're from Mars when you ask about MECP (or scoff at MECP), go someplace else. While MECP isn't the only good certification, it exists so the average level of competence can be raised and they have been around close to 20 years. The basic test is pretty simple but it does involve exactly what your system needs and the 1st Class test is more involved, technically. Master is even better, if they have one. FWIW, I had 1st class certification, twice.

Basically, if the installers are certified, they won't be wasting your time. The only problem with going to a car audio shop is that they may not have a way to run the engine for any length of time and dragging it to/from the water will only waste your time and pi$$ you off.

To save time and your money, I'm going to ask:
--Do the power cables go from the battery to a distribution block (both, not just one)?
--Is the power cable at least 4 ga? I didn't see a power rating for your amps- if they add up to 500W or more, you need larger cable. If the cable run is less than 12', 4ga may be OK.
--Measure the voltage from terminal to terminal at the battery, then repeat this at each amplifier's power terminals- if you see any difference, you have a problem and this is why you have noise.

Aric'sX15
07-11-2011, 03:45 PM
I have two 600 watt amps. im not sure what gauge the power wire is, because as i have mentioned before, its all factory wiring. the power cables run from the back of the boat off the DC switch by the two batteries. ive grounded the amps off the batteries, and ive even tried running the positive wires to the battery. that didnt work either. so im thinking its either a faulty head unit or something really easy im not looking at.

JimN
07-11-2011, 03:58 PM
I have two 600 watt amps. im not sure what gauge the power wire is, because as i have mentioned before, its all factory wiring. the power cables run from the back of the boat off the DC switch by the two batteries. ive grounded the amps off the batteries, and ive even tried running the positive wires to the battery. that didnt work either. so im thinking its either a faulty head unit or something really easy im not looking at.

It's probably not a faulty head unit because it didn't occur before the second amp was installed, right?

You're trying to drive 1200W (max) using the cable that was intended for 600W. That can't work.

What size is the cable that connects the second amp to the power cable?

The power formula of Ohm's Law states P=I x E, so 600 (W) = I x 12.5V and ot solve for I, you need to use 600W/12.5V = 48 Amperes. This assumes 100% efficiency, which is impossible. IIRC, 4 ga is good for 60A @ 8' and if your amp is more than 8' from the battery switch, you need to upgrade the power cabling to at least 2ga, preferably 1/0 in order for the amplifiers to get the voltage and current they need. A welding supply store will have cable for a decent price and you'll need to install the terminals correctly- crimp AND solder them. No crimpless/solderless crap.

Aric'sX15
07-11-2011, 04:39 PM
well theres two sets of power wires. there was a 250 watt amp that powered the two tower speakers. now that i have four, the noise got quite a bit more noticeable. it was there before, just not as bad.

Aric'sX15
07-13-2011, 12:49 AM
I also got a staticky noise from the speakers when I was using the tsunami fat sac pump from the 12v outlet by the drivers seat. What could that be?!!

davidstan
07-13-2011, 07:25 AM
My system works great until I turn on something electrical like the blower or the nav lights then I get the sickening static until I turn the unit off or the boat off. That's probably the best description I can give of my problem and also that for some reason I don't get the static out of my smaller amp for the 2 tower speakers. Any thoughts on this being a unique issue or is this common for the others having sound problems?

JimN
07-13-2011, 09:17 AM
well theres two sets of power wires. there was a 250 watt amp that powered the two tower speakers. now that i have four, the noise got quite a bit more noticeable. it was there before, just not as bad.

The wire gauge matters. Look on the power wires for any indication for gauge. Sharing power wires is a good way for noise to enter the audio system.

How old is your battery, and has it been run down completely?

Aric'sX15
07-13-2011, 12:34 PM
It's as old as the boat, so a little more than a year old. And
No, it's never been run down. I guess I could try running new power wires.

davidstan
07-17-2011, 07:59 AM
this is a pic of where all my grounds attach to a ground strip near the engine. On the left is the strip, the 2 middle bolts hold the 2 battery grounds and the outer bolts ground the amps and system. In all there are 8 ground cables attached.

davidstan
07-17-2011, 08:05 AM
Pic of the front of amp with rca cables to inside speakers

davidstan
07-17-2011, 08:12 AM
pic of rear of amp (limited on size i can download). i deinstalled amp last nite and cleaned the connection points and inspected wiring from amp ground point to battery ground. will reinstall today and see what happens or should i take amp to sound guy and let him run a test? Tower speakers with smaller amp works fine and actually so does the larger amp except when i turn on an accessory while system is playing. Will admit i am over my head.

JimN
07-17-2011, 11:26 AM
pic of rear of amp (limited on size i can download). i deinstalled amp last nite and cleaned the connection points and inspected wiring from amp ground point to battery ground. will reinstall today and see what happens or should i take amp to sound guy and let him run a test? Tower speakers with smaller amp works fine and actually so does the larger amp except when i turn on an accessory while system is playing. Will admit i am over my head.

If it was mine, I would separate the audio system from the rest of the electrical system except for using the same battery. This means running a separate power and ground cable to the amp location from the battery, using distribution blocks on each, running a 12ga power & ground feed to the head unit from the distribution block and using the switched radio wire a from the dash as a way to trigger a relay, so the radio isn't on constantly.

These links are for a site that deals with 12VDC systems and there's a lot of useful information. They have an installer locator, too.

Relays-
http://www.the12volt.com/relays/relays.asp

Cable size/capacity
http://www.the12volt.com/info/recwirsz.asp

The battery acts like a big filter if it's in good condition. The alternator has filtering inside too, but if it's being overtaxed, that filtering breaks down and doesn't work well.

You posted that one amp is rated at 600W and the other is rated at 250W. Look at all of the fuses on each amp and add them together- the 600W amp should have at least two 30A fuses, possibly with a 5A and the 250W amp should have at least one 40A or two 20-25A fuses. Amplifiers aren't 100% efficient and this will show up in the fuses they have- generally, you can multiply the fuse ratings by 14.4 to find the worst-case power number. If that falls far short of 250W and 600W, you know the amps aren't really putting out what they say but the fuse ratings should be used for sizing the alternator and power cables. Also, amplifier power ratings aren't always accurate, meaning that the marketing department got to state the output instead of the engineering department. An amp that's rated for 600W and has 40A of fuses doesn't put out 600W for very long- possibly only on dynamic peaks. Add the fuses and post the total for each amp- if it falls below the numbers above, the amp is either not putting out what they say or they're Class D, which is more efficient.

The reason I wrote this is for finding out what wire gauge to use. Whether the amps put out what they say doesn't matter to me- I'm just trying to find the cause of the noise. Also, the current ratings will show whether your alternator is adequate for what you're trying to do. It's likely that your alternator can't handle the demands placed on it. The factory alternator is rated for about 85-90A. If your amplifiers have 30A and 50A fuse ratings and all of the boat's accessories add up to 60A, you need a high output alternator in order to power all of the amplifiers. A second battery helps but the alternator still needs to be able to supply enough to keep the batteries charged while the engine and audio system are operating.

JimN
07-17-2011, 11:35 AM
pic of rear of amp (limited on size i can download). i deinstalled amp last nite and cleaned the connection points and inspected wiring from amp ground point to battery ground. will reinstall today and see what happens or should i take amp to sound guy and let him run a test? Tower speakers with smaller amp works fine and actually so does the larger amp except when i turn on an accessory while system is playing. Will admit i am over my head.

The photos are kind of small and they aren't clear when I zoom in- is there a way to upload larger ones, maybe using a digital camera?

Aric'sX15
07-17-2011, 12:49 PM
If it was mine, I would separate the audio system from the rest of the electrical system except for using the same battery. This means running a separate power and ground cable to the amp location from the battery, using distribution blocks on each, running a 12ga power & ground feed to the head unit from the distribution block and using the switched radio wire a from the dash as a way to trigger a relay, so the radio isn't on constantly.

These links are for a site that deals with 12VDC systems and there's a lot of useful information. They have an installer locator, too.

Relays-
http://www.the12volt.com/relays/relays.asp

Cable size/capacity
http://www.the12volt.com/info/recwirsz.asp

The battery acts like a big filter if it's in good condition. The alternator has filtering inside too, but if it's being overtaxed, that filtering breaks down and doesn't work well.

You posted that one amp is rated at 600W and the other is rated at 250W. Look at all of the fuses on each amp and add them together- the 600W amp should have at least two 30A fuses, possibly with a 5A and the 250W amp should have at least one 40A or two 20-25A fuses. Amplifiers aren't 100% efficient and this will show up in the fuses they have- generally, you can multiply the fuse ratings by 14.4 to find the worst-case power number. If that falls far short of 250W and 600W, you know the amps aren't really putting out what they say but the fuse ratings should be used for sizing the alternator and power cables. Also, amplifier power ratings aren't always accurate, meaning that the marketing department got to state the output instead of the engineering department. An amp that's rated for 600W and has 40A of fuses doesn't put out 600W for very long- possibly only on dynamic peaks. Add the fuses and post the total for each amp- if it falls below the numbers above, the amp is either not putting out what they say or they're Class D, which is more efficient.

The reason I wrote this is for finding out what wire gauge to use. Whether the amps put out what they say doesn't matter to me- I'm just trying to find the cause of the noise. Also, the current ratings will show whether your alternator is adequate for what you're trying to do. It's likely that your alternator can't handle the demands placed on it. The factory alternator is rated for about 85-90A. If your amplifiers have 30A and 50A fuse ratings and all of the boat's accessories add up to 60A, you need a high output alternator in order to power all of the amplifiers. A second battery helps but the alternator still needs to be able to supply enough to keep the batteries charged while the engine and audio system are operating.

i have two 600 watt amps. so youre saying i should get a third battery, and re wire it completely to where i dont even use the ignition?

JimN
07-17-2011, 06:54 PM
i have two 600 watt amps. so youre saying i should get a third battery, and re wire it completely to where i dont even use the ignition?

OK, two 600W amps makes the problem worse. Your alternator will die if you present excessive demand, based on its rating. The charging lead is too small to carry the current drawn by the amplifiers and the rest of the accessories, including the ECM, will eventually have problems because of the voltage drop caused by the load. Think of what happens if you have a toaster, a ton of Christmas tree lights and a window air conditioner plugged into the same outlet. It works the same way, whether the voltage is AC or DC.

The ignition lead would only be used for triggering the relay that turns the head unit on, nothing else. The power cables would only be used for the amplifiers and the 12ga wires to the head unit. The head unit's blue lead turns the amplifiers on. That's the best way to keep other devices from affecting the audio system- it allows the battery to filter out any noise that would be conducted through shared power wires.

The third battery will only help if the alternator is capable of handling the current demands of all of the electronics. A third battery on a small alternator just adds to the alternator's load and will speed up it's demise.

davidstan
07-17-2011, 07:28 PM
Thx for the advice on the batteries. I may have one weak battery according to the previous owner. One battery however is new this year. I will check that out and thx again.

JimN
07-17-2011, 08:25 PM
Thx for the advice on the batteries. I may have one weak battery according to the previous owner. One battery however is new this year. I will check that out and thx again.

All batteries in a multi-battery system should be in the same condition. The weak one will add a serious load to the charging system that will accelerate its failure.

Aric'sX15
07-17-2011, 09:27 PM
OK, two 600W amps makes the problem worse. Your alternator will die if you present excessive demand, based on its rating. The charging lead is too small to carry the current drawn by the amplifiers and the rest of the accessories, including the ECM, will eventually have problems because of the voltage drop caused by the load. Think of what happens if you have a toaster, a ton of Christmas tree lights and a window air conditioner plugged into the same outlet. It works the same way, whether the voltage is AC or DC.

The ignition lead would only be used for triggering the relay that turns the head unit on, nothing else. The power cables would only be used for the amplifiers and the 12ga wires to the head unit. The head unit's blue lead turns the amplifiers on. That's the best way to keep other devices from affecting the audio system- it allows the battery to filter out any noise that would be conducted through shared power wires.

The third battery will only help if the alternator is capable of handling the current demands of all of the electronics. A third battery on a small alternator just adds to the alternator's load and will speed up it's demise.

but its all factory wired. i dont see how this could be causing the noise? even when the other amp is un plugged it still makes the noise from the cabin speakers.

JimN
07-17-2011, 09:51 PM
but its all factory wired. i dont see how this could be causing the noise? even when the other amp is un plugged it still makes the noise from the cabin speakers.

"Factory wired" never included two 600W amplifiers. The fact that it makes noise when the second one is disconnected means that someone either didn't install it correctly or the amp may have been installed to replace another that was original, as an upgrade after it left the factory.

Is this model the one that was on the invoice when the boat was ordered? As an example that annoyed us at the second dealership I worked for, another manufacturer of ski/wakeboard boats would ship theirs with every wire from the head unit to the amp bundled together. That's a major F-up and it made a lot of noise that was really annoying. They even created a service incident number to cover the repair of it, which I think is totally stupid. They should have fixed the problem but instead, the answer I got to my question "Who installs this stuff for you" was "We have a guy here who's good at it". I told the service manager "No, he's not and here's why....". 2 hours were added to prep time for every boat that we had to deliver, whether we were swamped, or not.

BTW- the fact that something comes from the factory with certain equipment doesn't mean it was installed correctly. As much as I like MC, they just can't afford to hire people who are extremely experienced with this- if it's designed correctly and something is added after the fact, the design is no longer correct and it wasn't the engineer who messed with it. You can't add big amplifiers to wire that was sized for smaller amplifiers and have everything work the way it's supposed to. Period.

If you have noise when the only speakers working are connected to the head unit and the head unit is not connected to the amplifiers, you either have a problem with the head unit, the alternator (which could have been caused by adding extra amplifiers) or the noise is getting into the head unit through RF/EMI radiation. RF is Radio Frequency and EMI is Electro Magnetic Induction.

Disconnect the amps from the head unit and pull their fuses. If you have one speaker connected to each channel of the head unit and you still have noise, disconnect the head unit from the dash wiring and run a + & - wire from the battery to the head unit. If it cleans up, do the heavy gauge power cables/distribution block power feed replacement I described before but you still need a higher capacity alternator if you want to use these amplifiers. Also, you need to put a fuse or circuit breaker within 12" of the positive battery terminal used for the amplifier feed. This isn't an option, it's for your safety.

Thrall
07-18-2011, 10:00 AM
but its all factory wired. i dont see how this could be causing the noise? even when the other amp is un plugged it still makes the noise from the cabin speakers.

My X2 was "factory wired" with only one little amp and there was "noise" in the system.
You don't necessarily need 3 batteries for 2 - 600W amps. Just good clean connections, proper guage wire, good grounding and strong batteries.
I'm running about 2300W, 3 amps, although 2 of the amps aren't being used totally to their capacity, conservatively say 1800 W off of a single Odyssey gel battery (2 battery system, 1 for start/boat loads one for house loads). Good maint/recharging of the batteries after being on the lake all day and it runs fine.
"Noise" while running 12V acc, like the ballast pump indicates sub standard grounding typically.
As was said before, if all this stuff is just cobbed onto the battery terminals, it's probably not going to all run right.

JimN
07-18-2011, 12:37 PM
My X2 was "factory wired" with only one little amp and there was "noise" in the system.
You don't necessarily need 3 batteries for 2 - 600W amps. Just good clean connections, proper guage wire, good grounding and strong batteries.
I'm running about 2300W, 3 amps, although 2 of the amps aren't being used totally to their capacity, conservatively say 1800 W off of a single Odyssey gel battery (2 battery system, 1 for start/boat loads one for house loads). Good maint/recharging of the batteries after being on the lake all day and it runs fine.
"Noise" while running 12V acc, like the ballast pump indicates sub standard grounding typically.
As was said before, if all this stuff is just cobbed onto the battery terminals, it's probably not going to all run right.

What is needed to supply power depends on the amplifiers, though. If they're set up correctly, the music isn't too demanding and the amplifiers are relatively efficient, it's not as bad. If it's always played ballz to the wall with heavy, sustained bass, it should get everything you have.

1800W @100% efficiency and 14.4VDC is right at 125A. That's more than a stock alternator will do on its best day. Throw in less efficiency, say 75% (which is really good), and it goes up to 167A. Drop the idle voltage to 12.5 (pretty typical) and the 100% current is 144A, 192A@ 75%.

Regardless, the charging system and power supply are all-important if an electrical system is expected to work properly.

davidstan
07-18-2011, 01:52 PM
Testing tapatalk

davidstan
07-30-2011, 07:13 AM
Hiss/whine update, i installed a ground loop isolator between the head and amps and eureka the annoying part of the problem is gone. I still have a slight hiss that can only be heard when i turn the sound down real low. Will still try to get to a complete solution but for now i am at least able to enjoy the system w/o having to turn it off when the hiss amps up.

JimN
07-30-2011, 08:34 AM
Hiss/whine update, i installed a ground loop isolator between the head and amps and eureka the annoying part of the problem is gone. I still have a slight hiss that can only be heard when i turn the sound down real low. Will still try to get to a complete solution but for now i am at least able to enjoy the system w/o having to turn it off when the hiss amps up.

Is the residual noise kind of like "sssssssssssssssssssss"? That may be a level setting issue. Can you show the input level controls on the amp for the full-range speakers?

davidstan
07-30-2011, 06:41 PM
Is the residual noise kind of like "sssssssssssssssssssss"? That may be a level setting issue. Can you show the input level controls on the amp for the full-range speakers?

Jim, more like a metallic buzz but tried adjuting input sens and all it did was lower the buzz but also lowered the overall music sound. Buzz goes in and out which is odd. The isolator is only sitting between the 4 inside speakers. I have no isolator connected to the sub or tower amp.

sp00ky
07-30-2011, 07:28 PM
Try not to run the power and ground wires together. IE. on the same side of the boat

Aric'sX15
07-30-2011, 08:21 PM
Hiss/whine update, i installed a ground loop isolator between the head and amps and eureka the annoying part of the problem is gone. I still have a slight hiss that can only be heard when i turn the sound down real low. Will still try to get to a complete solution but for now i am at least able to enjoy the system w/o having to turn it off when the hiss amps up.

wish the ground loop isolator would have worked for me! what brand did you use? i used the radioshack ones and that might be my problem.

JimN
07-30-2011, 08:53 PM
Jim, more like a metallic buzz but tried adjuting input sens and all it did was lower the buzz but also lowered the overall music sound. Buzz goes in and out which is odd. The isolator is only sitting between the 4 inside speakers. I have no isolator connected to the sub or tower amp.

Does the pitch go up and down with RPM? That could be the alternator's filtering that's failing or being overtaxed.

You didn't turn the input controls all the way up, did you?

davidstan
07-31-2011, 07:42 AM
Does the pitch go up and down with RPM? That could be the alternator's filtering that's failing or being overtaxed.

You didn't turn the input controls all the way up, did you?
i used the radio shack isolator. Did not notice the pitch going up with rpm like i used to and no i turned input the other way (downward) til pitch was gone but so was all sound.

JimN
07-31-2011, 08:17 AM
i used the radio shack isolator. Did not notice the pitch going up with rpm like i used to and no i turned input the other way (downward) til pitch was gone but so was all sound.

I mentioned the JL setup procedure for the level controls. You need to go to their site and do what is in the instructions in order to get the most out of the system, both in clean power output and noise level. The controls are on an amplifier because the output level isn't the same from all manufacturers. An amplifier needs to see a specific voltage in order to develop its rated power output and if it's too high, you don't get whatever the rating shows. If the input voltage is too high, the amplifier will distort- not only does this sound bad but it also damages speakers.

davidstan
08-07-2011, 08:26 AM
The isolators have dampened the hiss by roughly 80 percent so it is liveable but i like to make perfection the enemy of the good so will pull the HU and check all those connections. I swapped the power cables from one amp to the good amp/speakers and still get the slight metallic hiss from the same speakers so it is not the power cable/ground and it does not go up and down with throttle input. I also noted that the noise will not start until i have been running the boat for 10 min or so and flip a switch like the trim tab or anc lights. I repeat myself because this all seems strange to me.

JimN
08-07-2011, 09:08 AM
The isolators have dampened the hiss by roughly 80 percent so it is liveable but i like to make perfection the enemy of the good so will pull the HU and check all those connections. I swapped the power cables from one amp to the good amp/speakers and still get the slight metallic hiss from the same speakers so it is not the power cable/ground and it does not go up and down with throttle input. I also noted that the noise will not start until i have been running the boat for 10 min or so and flip a switch like the trim tab or anc lights. I repeat myself because this all seems strange to me.

Have you measured for voltage drops, anywhere? I posted it before- power supply connections, cable size and connection quality are the most important parts of a circuit. If the voltage at the battery end of the wire is higher than at the here the device is connected, the cable size is inadequate. You can check this right at the battery and amp- connect the meter leads to the battery posts when the audio system is playing and make note of the voltage. Then, measure at the + and - terminals on each amp. If the numbers aren't very close, the cable is too small and/or you have resistance somewhere that is causing it. Under high demand, the voltage will drop a little but if the power supply system (battery, cabling and alternator) are adequate, it shouldn't drop much at all (it may drop a few tenths of a volt but more isn't good). You can check this along the cable, too but with long cable runs, it's not as easy.

If the symptoms seem strange to you, I would recommend reading more about how voltage and current are affected by resistance in 12VDC circuits.

davidstan
09-19-2011, 05:01 PM
Ok. I hope my last update and knock on wood. While i think someone earlier posted that the feedback hiss/static whatever you want to call it would be a PITA to resolve i also knew that i would eventually stumble upon a 100% cure. Strangely this happen a few weeks ago and i hesitated declaring small victory till I was certain the hiss was gone. Well, i tried just about everything a novice can do including replacing a 80% good battery but as i was somewhat satisfied with a reduction to a faint very slight hiss i settled. So i gathered up all the RCA and other wires and bundled them as recommended and stumble happened. Fired the boat up the next day and did a run and listened for the faint hiss but nothing but sweet clear music! 3 weekends in a row and no static. Still cant believe it but very thankful it seems to be gone as is my bogey man.

jvbaca
09-20-2011, 01:02 PM
So what did you do to solve it? Maybe I just didn't read your post right...... :-) Was it all the boat speakers or just the cabin or just the tower speakers?

davidstan
09-21-2011, 06:54 AM
I gathered up all the cables and bundled them neatly zip tied under the ski storage area as I was thinking I would have to live with a little slight hiss but found that this actually (by luck) eliminated the hiss 100%. Maybe it will come back but for now it is sweet.