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JRW160
01-30-2012, 10:39 AM
I am getting a lot of noise from my speakers, and it seems I have a ground loop problem. To elminate a lot of variables, I've unplugged a couple of amps and my 2nd battery bank, but I still have the problem.

I'm running a wetsounds ws420 as my source, and I have it wired directly to the battery with 16 gauge wire. I have a kicker zx350.4 wired with 4 gauge to a distribution block and the distribution block is connected to the battery with 0gauge. The negative of the battery is grounded to the engine with 2gauge from the factory. Whenever I plug both rcas into the amp, I get noise out of the speakers. If I only plug one rca in, there is no noise.

As a test, I ran rcas from the head unit directly to the amp, and I did not get the noise. It seems to me that the problem is the ws420, but I'm not sure how to fix it.

swatguy
01-30-2012, 12:46 PM
I am assuming u have some WS speakers? Can u give a description of your speakers? What kind of noise is it.....like a white noise? Does it stay constant or increase with engine rpm?

It is not uncommon to get a little white noise/ hiss from the huge HLCD speakers. They are powerful and the horn picks up some noise. I chased this issue for a week re wiring my stuff. The 420 has a built in line driver so adds to the signal. If you are running a 2volt out pre amp head unit it amplifies this issue due to the fact the gains on your amp will be a bit high. The best solution for me was upgrading to a 4v out head unit per WS and my local stereo shop to ease the white noise factor. The other thing to check is where your gains are set on the ws420 for the towers. Its usually the mid that give the most noise when incorrectly adjusted. Also make sure the mic is turned all the way to zero. Again this is all assuming you have a constqnt white noise situation which is normally attributed to gain and level issues than a ground loop.

JRW160
01-30-2012, 12:54 PM
The noise is on the factory clarion in boat speakers. It's a hiss. I have not turned the engine on.

I am not using my head unit at all. I am running sound directly into the aux port on the ws420. I will check the gains when I get home. I am not sure where they are set.

swatguy
01-30-2012, 01:35 PM
I can almost bet for certain its the gain levels on the 420's for your cabins. The fact the amp is powered for them and then you introduce the built line driver from the Ws420 which I think is (6 or 8 volts again off top of my head I don't recall the voltage,but its around there and will for sure give you that hiss thru you cabins if not adjusted properly). Try the mid level adjustment first. Also how old is your 420? Just trying to fog out if u have the newer version no dials on top of unit or original version with addition adjustments on the top of the unit

Btw had a feeling it was your interiors because if u were powering hlcds with that 350 it would be a waste of speakers.


To dial in your system turn the gain on you amp down. Turn volume on your head unit to 3/4 and make sure you 420 cabin volume isturned up as well Adjust gain on the amp until the sound starts to distort and then back it down a touch. Make sure all your head unit treble and bass are flat ie O. Fades are flat. And the equal controls are flat. In the center and the adjust eq according to your style.

JRW160
01-30-2012, 01:46 PM
The eq is one of the newer ones without the dials on top. It is less than a year old. I will check the gains on the ws420 when I get home from work.

swatguy
01-30-2012, 01:49 PM
Cool. Makes it way easier to do the adjustments to get it dialed in. It sounds more like a gain issue than an electrical ground loop one.

JRW160
01-30-2012, 01:58 PM
I hope so...

JimN
01-30-2012, 02:00 PM
I am getting a lot of noise from my speakers, and it seems I have a ground loop problem. To elminate a lot of variables, I've unplugged a couple of amps and my 2nd battery bank, but I still have the problem.

I'm running a wetsounds ws420 as my source, and I have it wired directly to the battery with 16 gauge wire. I have a kicker zx350.4 wired with 4 gauge to a distribution block and the distribution block is connected to the battery with 0gauge. The negative of the battery is grounded to the engine with 2gauge from the factory. Whenever I plug both rcas into the amp, I get noise out of the speakers. If I only plug one rca in, there is no noise.

As a test, I ran rcas from the head unit directly to the amp, and I did not get the noise. It seems to me that the problem is the ws420, but I'm not sure how to fix it.

Is it hissing, or whining? If it's hissing, it's not a ground loop- it just needs to have the levels set correctly (and WIDE OPEN doesn't equal 'correctly').

JRW160
01-30-2012, 03:14 PM
Is it hissing, or whining? If it's hissing, it's not a ground loop- it just needs to have the levels set correctly (and WIDE OPEN doesn't equal 'correctly').
It's hissing

JimN
01-30-2012, 03:34 PM
It's hissing

That's a gain issue if you hear hiss without any frequency shift with RPM.

Turn the amp's input control(s) down so you barely hear anything when the head unit is close to maximum. If you have an equalizer between the head unit and amp(s), turn that down close to minimum, too. If you use the bass control a lot, leave it in a typical position, then turn the volume up until you hear it distort- this is usually around 3/4 up the dial. With the head unit at the point of distortion, make note of the setting (usually, they show it numerically) and raise the input control for the next device in line- if it's an equalizer or amp- until you start to hear distortion while wearing hearing protection. I mention hearing protection because at high SPL, human hearing isn't as sensitive to distortion and it will be much easier to hear. Don't expect it to sound like a fuzzed out guitar- listen for it to sound gritty and edgy with more treble. Once it reaches the point of distortion, back it off a bit and mark the position of the control with a pencil, then back it off so you can repeat for each remaining channel.

Once the head unit's distortion point has been established, you can also increase the EQ/amp input controls until the hiss is barely audible. If you always head hissing, it's possible that an amp has faulty resistors or something like that.

EarmarkMarine
01-30-2012, 05:05 PM
JRW160,
JimN will have you dialed-in related to the hiss issue.

However, I did notice something else that you wrote in the OP which could be a concern.
The EQ should be ground and supplied from a point as close to the primary terminals of your amplifiers as possible. I would prefer this reference point versus the battery location. I would want the absolute minimum resistance and voltage potential between the components in the signal path. If the amplifiers are very close to the batteries it may not make a difference but this distinction would be more important if the amplifiers are separated from the batteries by some distance. I would use no less than a 14 gauge power and ground to the EQ and maybe a 12 gauge if the distance approaches 20 feet. Its not the cause of your existing hiss but this is a general approach to avoid other types of noise.

David
Earmark Marine

JRW160
01-30-2012, 08:48 PM
Thanks for all the help.

The levels on the ws420 don't seem to affect the hiss at all. I was able to get rid of the hiss by turning the gain on the amp all the way down.

When I hook the amp up directly to the head unit, I don't get any hiss with the amp gains up. What is the explanation for this?

JRW160
01-30-2012, 08:52 PM
JRW160,
JimN will have you dialed-in related to the hiss issue.

However, I did notice something else that you wrote in the OP which could be a concern.
The EQ should be ground and supplied from a point as close to the primary terminals of your amplifiers as possible. I would prefer this reference point versus the battery location. I would want the absolute minimum resistance and voltage potential between the components in the signal path. If the amplifiers are very close to the batteries it may not make a difference but this distinction would be more important if the amplifiers are separated from the batteries by some distance. I would use no less than a 14 gauge power and ground to the EQ and maybe a 12 gauge if the distance approaches 20 feet. Its not the cause of your existing hiss but this is a general approach to avoid other types of noise.

David
Earmark Marine
Thanks for the info. The amp is separated from the battery by 2ft of 0ga and 1ft of 4ga cable. I will run lines to get the ws420 grounded and supplied from the same point.

JimN
02-01-2012, 11:15 AM
Thanks for all the help.

The levels on the ws420 don't seem to affect the hiss at all. I was able to get rid of the hiss by turning the gain on the amp all the way down.

When I hook the amp up directly to the head unit, I don't get any hiss with the amp gains up. What is the explanation for this?

The WS420 may have some kind of problem- usually, an equalizer should be set up for "unity gain', meaning that the output signal is no higher than the input signal when the controls are at their 0 setting (they usually have a +/- XdB range). If you hear hiss, it's sometimes a bad op-amp, resistor or an impedance mis-match. Back in the '80s, a really good way to guarantee noise in a car audio system was to match an Audio Control equalizer with an ADS power amp. Most other brands worked well together but that combo was a PITA, although it was a good teaching experience WRT getting rid of noise issues.

You might want to contact Wetsounds-(1-877-938-7757)

JRW160
03-09-2012, 11:56 PM
Turns out the ws420 was the problem. JimN was spot on. After I installed my new tower speakers, I was able to better diagnose the problem. The tower output was clean, but the boat output was putting out a lot of noise. I sent it back to wet sounds and they sent me a new one. I installed it tonight and everything is good.

venetrex
03-12-2012, 08:19 PM
I have this same trouble with my wetsounds ws420 EQ. I have a JL Ausio HD600 amp powering 4 Bullet HLCD speakers and when the volume levels are low, I get a ton of hissing from the tower speakers only. I can turn down the amp gain, trouble is the output of the tower speakers is less. This has been a frustrating problem. It is not a grounding issue like a thread on another forum suggested. It is also not the inputs to the WS420 because If I unplug the RCA's going into it the noise is still there. I had this problem with the regular jl audio tower speakers as well. I'll bet you still have your trouble. LEt me know, This has been very frustrating.

JRW160
03-12-2012, 09:06 PM
Mine is fixed now with the new ws420.

Have you tried a different amp?

EarmarkMarine
03-12-2012, 09:37 PM
venetrex,
Hiss, as in the constant sound of a distant waterfall, is referred to as 'thermal noise' which is a normal part of all electronics. It's just a matter of to what degree.
Speakers do not hiss. However, an HLCD is a little bright and very sensitive so it will ruthlessly produce anything that it receives.
If you unplug the amplifier's RCA input and turn the gain to 1/2 you should have hiss that is minimal.
Then plug back in the input RCAs on the amplifier and introduce the next component in reverse in the signal path with it's input unplugged.
Do this until a significant amount of noise returns to narrow down the culprit. But leave the amplifier input gain at 50 percent.
Also, the JL Audio amplifier has two input sensitivity settings based on the amount of voltage it will receive. The EQ has the higher voltage so the amplifier should be on the higher voltage/lower sensitivity setting.
Of course the volume will go down when you reduce the input gain on the amplifier without an offsetting adjustment on the source unit volume control. However, an amplifier input gain is not intended to be a volume control. As long as the source unit is not being driven into clipping a lower amplifier input setting is not limiting either the clean, unclipped volume ceiling or the dynamic range potential. Too high of an amplifier input setting is the number one cause of hiss and noise. With the high output voltage of an EQ/line driver the amplifier input gain level should be fairly low.

David
Earmark Marine

swatguy
03-12-2012, 10:37 PM
Ditto what David said,

When I swapped from 6.5 hlcd's to the Pro 80's and the Rev 8's I chased a white noise coming from them for ever til I took it to the pros. A small hiss for lake of better description like a white noise is completely normal from the bigger HLCD speakers. The key that toned it down for me was adding a 4v output head unit like an Alpine. It was still noticeable,but the 4v output allowed me to run a lower gain on the amps with around same output.