Newbie Requesting help

[Jeffdachef 5,000+ posts]

I begun work on my upgrades yesterday afternoon. The box should be done and ready today. However, I came across an issue I'm hoping to get help with from you guys : )
There is a whistling noise as soon as the car starts, the HU is turned off or in demo mode but the 'whistling' noise starts as soon as I start the car i.e. power the electricals & they come from the 6x9s and components. Accelerating changes the whistling noise "tune" so does using power window switches. The noise started only after the new mono block was connected.

How may I fix this : S

What you are experiencing is alternator whine/ ground loop (google those up if you want to know more)

Do you have your RCAs running on the opposite side of your power wire? Make sure RCAS and power wires are not close to eachother.

Make sure your amps are not mounted on a metal surface, put a sheet of wood in between because the amplifier chassis can cause a ground loop sometimes too.

Another thing you can do is to ground your Head unit RCA.

strip a 4-5" section of wire, wrap one end around the exposed part of 1 rca and attach the other end of it to the headunit case via a screw on the case, you should be able to access a few.

Make sure your head unit is well grounded too.

 

[Maky 10+ year member]

What you are experiencing is alternator whine/ ground loop (google those up if you want to know more)
Do you have your RCAs running on the opposite side of your power wire? Make sure RCAS and power wires are not close to eachother.

Make sure your amps are not mounted on a metal surface, put a sheet of wood in between because the amplifier chassis can cause a ground loop sometimes too.

Another thing you can do is to ground your Head unit RCA.

strip a 4-5" section of wire, wrap one end around the exposed part of 1 rca and attach the other end of it to the headunit case via a screw on the case, you should be able to access a few.

Make sure your head unit is well grounded too.

I will double check this afternoon when we resume but I think what he's done is laid the RCAs on one side and Power Supply on the other. We removed the power to the mono block yesterday and the noise stopped so it definitely has something to do with the new amp.

I shall also have him look at the grounding once again and check for the metal surface below the amp. Is there anything else that could be causing this Jeff?

 

[Jeffdachef 5,000+ posts]

If those fixes dont work then move your monoblock's grounding point. The head unit RCA grounding solves the issue most of the times.

 

[Maky 10+ year member]

If those fixes dont work then move your monoblock's grounding point. The head unit RCA grounding solves the issue most of the times.

Righto! So the issue was & I'll try to describe it as close to what he said it was, The remote wire was sending a relay signal back to the HU and it was being broadcast through the speakers. I hope that made sense : P. He put some kind device passing through the remote wire to "cut off" the signal from going back. He did reground the wire before as well but that didn't help. There is no more any whistling noise.

The system sounds noticeably better than it did before. Much cleaner bass, vocals & overall a more balanced sound thanks to the mans tuning.

The custom ported box is still not made and I'll get it within a week. I can't wait to see what my system sounds like with the ported box. The guy was seriously recommending me not to go for ported but I told him internet people(you!) were adamant about the change : ).

*Awaits Box*...

 

[CSCStang]

You will like the difference. I ran sealed for way too many years and I won't look back now.

 

[Maky 10+ year member]

Another week for box as he switched his supplier -_-...

Now I have yet another issue, cropped up past couple of days. While playing music at higher volume there is a 'thumping noise' coming from the subwoofer. I got some time today to open up the boot and see/hear for myself. I will try to best describe the issue:

I listen to Volume 20 for the 'kick' i.e. point at which I'm satisfied with the bass. When I keep it at Volume 15 on certain(only specific tracks with specific bass notes) songs the sub is fine but when I turn it up to 20 it starts to make this thumping noise. I should mention that when it starts to make this banging noise the excursion of the subwoofer goes Insane.

What could the issue be? My current sealed box is about 18-19Ltr. is it too small now that the subwoofer is being provided adequate power? or some issue with the sub?

 

[Jeffdachef 5,000+ posts]

when I turn it up to 20 it starts to make this thumping noise. I should mention that when it starts to make this banging noise the excursion of the subwoofer goes Insane.
What could the issue be? My current sealed box is about 18-19Ltr. is it too small now that the subwoofer is being provided adequate power? or some issue with the sub?

1) does it sound like this?



2) or like this https://www.youtube.com/watch?v=bimMb_aFnWI

1, 2 or neither?

some tests you can do is pushing on the cone to see whats going on, check your current box for leaks. Take out your subwoofer and inspect/push on the spiders(cloth suspension) for rips. Then do a free air test, play the sub without a box and see if the problem happens.

 

[Maky 10+ year member]

1) does it sound like this?

It sounds very similar to No.2 after the 10 second mark Jeff.

There is also a hole at the side of the box. The hole is small but big enough to let 2 +/- connecting copper wires pass through. The hole although has been there since the beginning but this sound started only a few days ago and as mentioned only on certain songs when specific bass notes hit.

 

[Jeffdachef 5,000+ posts]

It sounds very similar to No.2 after the 10 second mark Jeff.There is also a hole at the side of the box. The hole is small but big enough to let 2 +/- connecting copper wires pass through. The hole although has been there since the beginning but this sound started only a few days ago and as mentioned only on certain songs when specific bass notes hit.

make sure you do all the tests i told you to do.

 

[Maky 10+ year member]

make sure you do all the tests i told you to do.

Alrighty Jeff...

My work schedule involves whole days and late into the night so I only get the one Sunday off where I can do things that might take up time. The man said the box should be ready on sSaturday evening so I shall have a look at the dealer itself. If it's still not ready by then I'll pop open the sub on sunday and have a look : ).

 

[Maky 10+ year member]

make sure you do all the tests i told you to do.

An Update.

I got some time to check out the Subwoofer close up while delivering my car for service and here is what I saw:

http://i.imgur.com/HT7GFZa.jpg

http://i.imgur.com/eIRAJNL.jpg

http://i.imgur.com/QwjwTUZ.jpg

I also opened up the Subwoofer and Inspected it for any other tears or anything outside normal. The suspension seems to have adequate resistance when I pushed it down so the spider should be fine, it wasn't super stiff the spider but then this subwoofer is 8 years old. I wasn't able to find any other problems. I think that broken off Surround is it Jeff...

 

[Jeffdachef 5,000+ posts]

An Update.
I got some time to check out the Subwoofer close up while delivering my car for service and here is what I saw:

http://i.imgur.com/HT7GFZa.jpg

http://i.imgur.com/eIRAJNL.jpg

http://i.imgur.com/QwjwTUZ.jpg

I also opened up the Subwoofer and Inspected it for any other tears or anything outside normal. The suspension seems to have adequate resistance when I pushed it down so the spider should be fine, it wasn't super stiff the spider but then this subwoofer is 8 years old. I wasn't able to find any other problems. I think that broken off Surround is it Jeff...

you can do a poor man's fix involving "amazing goop" not sure if you have that it bombay. Or you can get a 12" refoam kit off ebay. look up on how to do a refoam on youtube its quite easy.. If anything you can just get a new subwoofer if you dont want to fix it.

 

[Maky 10+ year member]

you can do a poor man's fix involving "amazing goop" not sure if you have that it bombay. Or you can get a 12" refoam kit off ebay. look up on how to do a refoam on youtube its quite easy.. If anything you can just get a new subwoofer if you dont want to fix it.

My only concern is the sound. If I do get the new surround kit will it sound the same? It already is almost 8 years old : S...

 

[Jeffdachef 5,000+ posts]

My only concern is the sound. If I do get the new surround kit will it sound the same? It already is almost 8 years old : S...

yup, still the same sound.

 

[Maky 10+ year member]

yup, still the same sound.

I'm glad to hear that.

Just in case though jeff. What would you recommend for that 'Bass hits - Kicks chest' type sub : )?

Again for your reference, I run the JBL GTO-751EZ amplifier.