DiyMobileAudio.com Car Stereo Forum banner

1 - 20 of 44 Posts

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #1
Next month I’m changing my sub setup from two B2 rage 12” ported to sealing off my trunk and going IB with two SI 18” in the baffle. With help from quickaudi07. We have identical cars so I’m driving to Chicago one weekend to change it over.

my question is about my power and grounds. I currently have two 1/0 running front to rear. No rear battery but do have a small Maxwell 58f super cap bank. Do I really need two 1/0 for positive? I run B2 2500.1 and 1200.6 amps. I’m wondering if I could change one over to ground to have a ground from front to rear also. Or am I better off keeping two 1/0 positive cable? Im Thinking about this because I seem to always be fighting a slight high pitch engine noise. No matter what I do it will not go away. Just this week I rechecked every connection under the hood and took a drill with a file brush to clean all connections. Didn’t help. Then did the same in the trunk. Slightly helped.
thenre did the head unit ground. I then added a chassis ground from head unit to cars frame then from that connection point ran a wire to the rear ground. Tried disconnecting the factory ground in the harness also.Nothing made any
difference.

If I unhook the rca from the input of the helix the noise goes away.
If I unhook the rca out from the helix to the amps it also goes away.
If I kept both 1/0 for power could I use smaller like 4ga for ground front to rear or does it need to be 1/0 also?

Turning the urc.3 volume knob down turns down the noise also. The noise does not change at all turning up the head unit volume.
I’m stumped and can’t think of anything else to try.
 

·
Premium Member
Joined
·
5,474 Posts
Maybe try making one of the 1/0 a ground?

Those RCAs to the HU may like a ground wire from the amp back to the HU running along side the RCAs to minimise "a loop"?
 

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #3
Those RCAs to the HU may like a ground wire from the amp back to the HU running along side the RCAs to minimise "a loop"?
That’s what I did by grounding the HU to the body then running a small ground from that ground location to the rear amps ground location.
 

·
Registered
Joined
·
1,081 Posts
Next month I’m changing my sub setup from two B2 rage 12” ported to sealing off my trunk and going IB with two SI 18” in the baffle. With help from quickaudi07. We have identical cars so I’m driving to Chicago one weekend to change it over.

my question is about my power and grounds. I currently have two 1/0 running front to rear. No rear battery but do have a small Maxwell 58f super cap bank. Do I really need two 1/0 for positive? I run B2 2500.1 and 1200.6 amps. I’m wondering if I could change one over to ground to have a ground from front to rear also. Or am I better off keeping two 1/0 positive cable? Im Thinking about this because I seem to always be fighting a slight high pitch engine noise. No matter what I do it will not go away. Just this week I rechecked every connection under the hood and took a drill with a file brush to clean all connections. Didn’t help. Then did the same in the trunk. Slightly helped.
thenre did the head unit ground. I then added a chassis ground from head unit to cars frame then from that connection point ran a wire to the rear ground. Tried disconnecting the factory ground in the harness also.Nothing made any
difference.

If I unhook the rca from the input of the helix the noise goes away.
If I unhook the rca out from the helix to the amps it also goes away.
If I kept both 1/0 for power could I use smaller like 4ga for ground front to rear or does it need to be 1/0 also?

Turning the urc.3 volume knob down turns down the noise also. The noise does not change at all turning up the head unit volume.
I’m stumped and can’t think of anything else to try.
Sorry I can't help with your issue, but I'm super anxious and envious about the two 18" IB subs 🙂 I still think this will have to be in my future ! I'm thinking a single 24" Stereo Integrity IB....
 

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #5
Maybe try making one of the 1/0 a ground?
That’s what I want to know... can I get by with only one 1/0 power to the rear with the wattage I’m running? 2500 to the subs plus the 6 channel for highs? If going by the recommended fuse rating of each amp
It would be 370 amps.

what does it tell us if I disconnect either the input RCAs or the output RCAs on the helix and the noise goes away. And that the helix usb.3 volume knob also controls the level of the noise.

I have tried all 3 positions on the ground switch on the helix. No change in the noise. One position did have a weird effect in that if I was muting all the channels to take measurements when tuning the subs would still play but at a lower volume. I remember I had this issue when I first hooked up the helix and even started a thread about it saying the subs not completely muting. Could there actually be something wrong with my helix? It makes no sense that the 3 position ground switch on the helix could result in the subs not completely muting
 

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #6
Here’s the link to my original thread back in November 2018 when I noticed the subs not completely muting and I even took pics of the measurements when I was tuning to prove it. How can that 3 position ground switch cause this? And before someone says am I sure the switch causes this to happen. Yes I am 100% sure it does. When I redid and cleaned up all the grounds in the car i checked all 3 positions so see if one had less noise before moving on to the next section of the car.

I’m almost convinced that my helix has something wrong with it somehow. Because sometimes when doing software upgrades the noise got worse. Then I would revert back to older software and the noise goes completely away for a short while, sometimes a week or two sometimes it’s only noise free after reverting the software back untill I shut everything down. When I get back in the car to go somewhere the noise is back.

there is no way it’s my wiring and grounds because I have redone them and completely required them a few times now and the only common thing is the helix and when it’s ground switch position makes the subs not completely mute is also the exact same time I’m always having this intermittent noise problem.

^
AHA!!!!!! That last sentence says it all. Somehow anytime in the last two years when I have had intermittent high pitch noise and start losing my mind trying everything to chase it down is also when the ground switch causes the helix to not completely mute the subs.
The two things always happens at the same time. (Noise/ subs not completely muting)
The helix controls how loud the noise is with the urc, and the helix ground switch causes the subs not muting on one of the positions.


Tomorrow I might revert back to the old software just to see if and for how long the noise stays gone. But I should not have to do this. The helix has to be faulty
 

·
Premium Member
Joined
·
5,474 Posts
That’s what I want to know... can I get by with only one 1/0 power to the rear with the wattage I’m running? 2500 to the subs plus the 6 channel for highs? If going by the recommended fuse rating of each amp
It would be 370 amps.
...
So you have amplifier fuses like 200A +170A?
Or are you dividing 2500W/12V and getting 200A and adding that to the 6 channel amplifier math?

If the amp only has 100A and the other amp only 100A, then the wire should seldom carry more than 200A.


...
what does it tell us if I disconnect either the input RCAs or the output RCAs on the helix and the noise goes away. And that the helix usb.3 volume knob also controls the level of the noise.
...
... Could there actually be something wrong with my helix? It makes no sense that the 3 position ground switch on the helix could result in the subs not completely muting
It tell us that a ground loop exists between the amp and the headunit. Break the loop, and the ground loop goes away.

There could be something wrong, but ground loops are notoriously problematic,

I would start with a pieces of wire and try temporary grounds from the amps to the Helix and HU to the Helix.
 

·
Registered
Joined
·
529 Posts
Holmz hit it, your amp(s)'s power and ground are fine. The ground loop is source related. You need to walk through a well thought out troubleshooting experiment to solve your issue.
 

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #9
Holmz hit it, your amp(s)'s power and ground are fine. The ground loop is source related. You need to walk through a well thought out troubleshooting experiment to solve your issue.
I’ve done everything I can think of for almost two years.
What do you suggest. I’m at a loss that’s why I’m posting here.

I have done...

1. redone all wiring and connections under the hood two times. Every time I even use a drill with a brush to make sure there is no corrosion and every connection is spotless.

2. two days ago I did the exact same things to the trunk connections.

3. then I went to the head unit and check snd redid the ground. I then added a ground from the head unit to the cars chassis ground up by my foot area. I then connected a ground from that point to the rear chassis ground which is basically the same as connecting the HU to the amps.

4. Tried disconnecting the ground in the factory harness didn’t make a difference. So hooked it back up.

5. tried grounding theRCAs on the HU to ground and that made insane noise. I’ve seen this work for some guys.
6. Tried one of those PAC ground isolator packs by the helix and didn’t make any difference.
7. Tried the PAC at the head unit and no difference.


one thing I think I noticed is that my ground from the rear to the 6 channel amp is different cable. It is welding cable I bought and they told me it was OFC but I am not so sure it actually is because I cut open an extra piece I had laying around and the copper was starting to darken and turn colors. To test this could I use maybe a speaker wire and connect it from the rear ground to the 6 channel? My amp is mounted to the rear deck and I can’t remove the wires from it without removing the amp completely so that’s a lot of work.
Or would just measuring the ohms while it’s connected be ok to do? How much resistance is acceptable?

I don’t know what else I could possibly try
 

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #10
I would start with a pieces of wire and try temporary grounds from the amps to the Helix and HU to the Helix.



is the helix chassis grounded or do I have to remove the ground from it snd splice into it to test to the amps and HU?
 

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #11
So you have amplifier fuses like 200A +170A?
Or are you dividing 2500W/12V and getting 200A and adding that to the 6 channel amplifier math?

If the amp only has 100A and the other amp only 100A, then the wire should seldom carry more than 200A.
no I didn’t divide 2500/12. I’m going by the recommended fuse sizes if each amp. The 2500.1 has a 250amp fuse inline and the 6 channel has a 120amp fuse For 370 total amps.

3700/12= 308 amps
3600/14= 264 amps
I have 370 amp alt,d3100 and small super cap bank so my voltage rarely drops under 14v even at full tilt. I highly doubt the 6 channel would ever pull 120amps because the tweets and mids will never use all its power. I would guess it uses 60-80max amps. But I think the sub amp could pull 250 amps when I’m full tilt.
 

·
Registered
Joined
·
529 Posts
I’ve done everything I can think of for almost two years.
What do you suggest. I’m at a loss that’s why I’m posting here.

I have done...

1. redone all wiring and connections under the hood two times. Every time I even use a drill with a brush to make sure there is no corrosion and every connection is spotless.

2. two days ago I did the exact same things to the trunk connections.

3. then I went to the head unit and check snd redid the ground. I then added a ground from the head unit to the cars chassis ground up by my foot area. I then connected a ground from that point to the rear chassis ground which is basically the same as connecting the HU to the amps.

4. Tried disconnecting the ground in the factory harness didn’t make a difference. So hooked it back up.

5. tried grounding theRCAs on the HU to ground and that made insane noise. I’ve seen this work for some guys.
6. Tried one of those PAC ground isolator packs by the helix and didn’t make any difference.
7. Tried the PAC at the head unit and no difference.


one thing I think I noticed is that my ground from the rear to the 6 channel amp is different cable. It is welding cable I bought and they told me it was OFC but I am not so sure it actually is because I cut open an extra piece I had laying around and the copper was starting to darken and turn colors. To test this could I use maybe a speaker wire and connect it from the rear ground to the 6 channel? My amp is mounted to the rear deck and I can’t remove the wires from it without removing the amp completely so that’s a lot of work.
Or would just measuring the ohms while it’s connected be ok to do? How much resistance is acceptable?

I don’t know what else I could possibly try
Ok lets start with the only good info that I have.
1. when you disconnect the RCA from the amps, there is no noise.

This means its something upstream of the RCAs. To double check this, first take a RCA to 3.5 mm cable and plug into a phone or laptop (running off of its internal battery so its isolated).
  • if you have noise, than we're wrong about amp grounds.
  • if you do not have noise, than we're correct and its something upstream of the amps.

Lets assume we're right and its something upstream.
1. add the helix back into the system.
2. use the rca to 3.5 mm as a signal input to the helix to test noise

Does the noise come back?
  • if yes, than we need to move the helix ground around until it stops. Try grounding at the same location as the amps. If you need to run the wiring external to car than do so.
  • if no, than the helix is fine as is (I would still move the ground to the shared amp ground location).

Now we're down to two possibilities:
1. RCA noise
2. HU ground loop
(3. bad source)

1. To rule out RCA's you can just run another set external to the car so you avoid any electrical noise.
2. HU ground should be at the same location as the amps and dsp. I know you've tried this but a good troubleshooting guide has to go in a logical order to isolate the issues.
- you could also use that 2nd 0 gauge run as a battery ground if nothing in the trunk is good.

Lazy fix (assuming helix is noise free) is just use a digital input :)
 

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #13
Ok lets start with the only good info that I have.
1. when you disconnect the RCA from the amps, there is no noise.

This means its something upstream of the RCAs. To double check this, first take a RCA to 3.5 mm cable and plug into a phone or laptop (running off of its internal battery so its isolated).
  • if you have noise, than we're wrong about amp grounds.
  • if you do not have noise, than we're correct and its something upstream of the amps.

Lets assume we're right and its something upstream.
1. add the helix back into the system.
2. use the rca to 3.5 mm as a signal input to the helix to test noise

Does the noise come back?
  • if yes, than we need to move the helix ground around until it stops. Try grounding at the same location as the amps. If you need to run the wiring external to car than do so.
  • if no, than the helix is fine as is (I would still move the ground to the shared amp ground location).

Now we're down to two possibilities:
1. RCA noise
2. HU ground loop
(3. bad source)

1. To rule out RCA's you can just run another set external to the car so you avoid any electrical noise.
2. HU ground should be at the same location as the amps and dsp. I know you've tried this but a good troubleshooting guide has to go in a logical order to isolate the issues.
- you could also use that 2nd 0 gauge run as a battery ground if nothing in the trunk is good.

Lazy fix (assuming helix is noise free) is just use a digital input :)
1. I’ll have to buy a cheap set of rca to test.
2. Is done.
3. still wondering if I should just do this anyways then that should make all of this moot point. I don’t have a clamp meter to see what total amperage I’m pulling is so not sure if I need two 1/0 or not. Is there a general rule of thumb? According to cable charts 1/0 can handle 250-300 for up to 19ft so it would be a close call. What’s the worse that would happen? A melt down? Or big voltage drop? I currently have zero drop. I have a gauge on front snd rear voltage and in fact the rear is usually .1v higher I’m guessing because the super cap bank is in the rear.


FYI: I got my tools and wire out and went to try what was said above and the noise is now so little that I have to concentrate to hear it and get close to the tweeters and only hear it from 1900-2200rpm if I’m really straining in parked car. I’m gonna take a drive but doubt I can hear it while driving or with the volume on anything besides 0. 🙄🤔
284285
 

·
Premium Member
Joined
·
5,474 Posts
no I didn’t divide 2500/12. I’m going by the recommended fuse sizes if each amp. The 2500.1 has a 250amp fuse inline and the 6 channel has a 120amp fuse For 370 total amps.

3700/12= 308 amps
3600/14= 264 amps
I have 370 amp alt,d3100 and small super cap bank so my voltage rarely drops under 14v even at full tilt. I highly doubt the 6 channel would ever pull 120amps because the tweets and mids will never use all its power. I would guess it uses 60-80max amps. But I think the sub amp could pull 250 amps when I’m full tilt.
The amp will only draw 250 when the fuse blows. It will always draw less.

I would only use that second cable as a ground as a way to test if a ground has any benefit.

If the 1/0 is only rated for 250A put a 250A fuse in the cable.


...
FYI: I got my tools and wire out and went to try what was said above and the noise is now so little that I have to concentrate to hear it and get close to the tweeters and only hear it from 1900-2200rpm if I’m really straining in parked car. I’m gonna take a drive but doubt I can hear it while driving or with the volume on anything besides 0. 🙄🤔
So the noise went away on its own? Or what was done?
 

·
Registered
Joined
·
529 Posts
1. I’ll have to buy a cheap set of rca to test.
2. Is done.
3. still wondering if I should just do this anyways then that should make all of this moot point. I don’t have a clamp meter to see what total amperage I’m pulling is so not sure if I need two 1/0 or not. Is there a general rule of thumb? According to cable charts 1/0 can handle 250-300 for up to 19ft so it would be a close call. What’s the worse that would happen? A melt down? Or big voltage drop? I currently have zero drop. I have a gauge on front snd rear voltage and in fact the rear is usually .1v higher I’m guessing because the super cap bank is in the rear.


FYI: I got my tools and wire out and went to try what was said above and the noise is now so little that I have to concentrate to hear it and get close to the tweeters and only hear it from 1900-2200rpm if I’m really straining in parked car. I’m gonna take a drive but doubt I can hear it while driving or with the volume on anything besides 0. 🙄🤔
View attachment 284285

Maybe you have the amp gain on the tweeter channel a touch high? Try reducing the gain and increase level on the helix a bit (if you've set the output a down a few dB).

You probably do not need a double 0 gauge run. Remember fuses on the wire just protect the wire, fuses at the amps protect the amps. Wire of a particular gauge has a certain amount of resistance per unit length. When you increase current over that length of wire you will see voltage drop depending on these specification. When the current draw exceeds the fuse rating the fuse will pop.
 

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #16
Maybe you have the amp gain on the tweeter channel a touch high? Try reducing the gain and increase level on the helix a bit (if you've set the output a down a few dB).

You probably do not need a double 0 gauge run. Remember fuses on the wire just protect the wire, fuses at the amps protect the amps. Wire of a particular gauge has a certain amount of resistance per unit length. When you increase current over that length of wire you will see voltage drop depending on these specification. When the current draw exceeds the fuse rating the fuse will pop.
the tweets channels gains in helix software are at 0 and I allready have the helix at +3 on the input gains. If I raise it past +3 the noise becomes obvious at all times So I can’t lower tweeter amp gains. Unless I could change the helix input sensitivity dial. It was set with a 0db track and HU 39 of 40 in the Kenwood So maybe that’s why I have to have gains up more than usual in the software input and output? Maybe I should use a -10db track at 39/40 Or use the same 0db but set the HU at 30 out of 40 then adjust the dial. I was being over cautious when I first set it since I had never had to do that before. I forgot all about that damn sensitivity dial till just now


And to answer the other question I did nothing for the noise to be less But I went to go to the store and it’s there slightly and I also hearing the subs pop when stuff turns on 😡 Could it be my sub amp again? I allready had to send it in once for the rca inputs grounds going bad somehow last summer causing all sorts of noise issues. Would that cause me to hear it in the tweets also? Damn B2 amps are junk! I’ve had nothing but problems with them since day one. The 6 channel will over heat if there is no fans on it even if it’s 0 degrees outside
 

·
Registered
Joined
·
529 Posts
I wouldn't recommend setting amp gains, particularly for an active system, with test tone tracks. My recommendation is go through that trouble shooting instruction bullet by bullet to see if the noise issue is resolved. After that you should set the amp gain by ear. I would use the tweeter as the output limiting driver, so set the gain of all other channels relative to the tweeters output capability w/o noise. If the troubleshooting steps do not improve the situation I would still recommend setting gains according to my suggestions above.

I know you're pissed at your gear but its best to try to resolve the issue before just buying new gear. Spending money on new **** to just have the same noise issue will suck even worse..
 

·
Registered
Joined
·
529 Posts
the tweets channels gains in helix software are at 0 and I allready have the helix at +3 on the input gains. If I raise it past +3 the noise becomes obvious at all times So I can’t lower tweeter amp gains. Unless I could change the helix input sensitivity dial. It was set with a 0db track and HU 39 of 40 in the Kenwood So maybe that’s why I have to have gains up more than usual in the software input and output? Maybe I should use a -10db track at 39/40 Or use the same 0db but set the HU at 30 out of 40 then adjust the dial. I was being over cautious when I first set it since I had never had to do that before. I forgot all about that damn sensitivity dial till just now
Set helix input to 0 and use amp gain to raise/lower level of the drivers. It sounds like you're increasing the noise floor from the HU by boosting it at the helix. I think you need to step through a gain setting exercises as well...
 

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #19
I wouldn't recommend setting amp gains, particularly for an active system, with test tone tracks. My recommendation is go through that trouble shooting instruction bullet by bullet to see if the noise issue is resolved. After that you should set the amp gain by ear. I would use the tweeter as the output limiting driver, so set the gain of all other channels relative to the tweeters output capability w/o noise. If the troubleshooting steps do not improve the situation I would still recommend setting gains according to my suggestions above.

I know you're pissed at your gear but its best to try to resolve the issue before just buying new gear. Spending money on new **** to just have the same noise issue will suck even worse..
The B2 amps both have had different issues from the start. The 6 channel when hot makes a weird sound from one channels speaker I even had a thread about it last summer. I took the bottom off it and installed two fans and that stopped. Indidnt want to sent it to B2 and have no sound at all for who knows how long. Then I had to send in the sub amp to have the rca fixed because their grounds inside the amp failed somehow and I believe one of them is again because I had less bass and decided to fade in my head unit and sure enough There was no bass when faded to one side To I had to go back and just barely move the rca. B2 uses good Tiffany style RCAs not the junk way too many amps use So it has to be failing internally again because the rca isn’t loose. Is this common for amps to break, possibly from all the vibrations? There is no other logical explanation why they keep failing because they are never touched. Tomorrow I’m going to disconnect the sub RCAs and see if they are causing the noise issue
 

·
Registered
2013 VW CC
Joined
·
518 Posts
Discussion Starter #20
Set helix input to 0 and use amp gain to raise/lower level of the drivers. It sounds like you're increasing the noise floor from the HU by boosting it at the helix. I think you need to step through a gain setting exercises as well...
This is not a gain issue. This noise is engine/alternator noise. Huge difference between the two. My noise floor is good. The Kenwood doesn’t make any hiss noise that’s audible even at max 40/40 there is no difference from max or 1.

As for the helix input gain. I I believe I tested with the dd1 and it didn’t clip untill +4

it also doesn’t produce audible hiss untill +4.
Anyways Back on the topic at hand which has nothing to do with gains please lol
 
1 - 20 of 44 Posts
Top