installed my audio need help please

[ash26ace]

ok so first i fitted a sub and an amp which works perfectly then on another occasion fitted some component speakers also wired to the amp. everything works perfect except there is an annoying crackling type sound when i turn it down or pause it. at first i thought it was a dodgy rca cable so i swapped it for the one that was in my sub and the sound went. so i bought a new cable to put in, did that ad then the sound came back so basically the sound is only there if both the sub and the speakers are connected.
any ideas?

 

[Sean.]

do you have seperate amps for the sub n comps?

where are you earths?

what equipment is it your using?

what HU?

what car?

by crackling, what do you mean?

 

[traffmeister]

as sean says i would use two amps one for sub and one for speakers.....this is much better way of supplying power!

 

[wallop]

ok so first i fitted a sub and an amp which works perfectly then on another occasion fitted some component speakers also wired to the amp. everything works perfect except there is an annoying crackling type sound when i turn it down or pause it. at first i thought it was a dodgy rca cable so i swapped it for the one that was in my sub and the sound went. so i bought a new cable to put in, did that ad then the sound came back so basically the sound is only there if both the sub and the speakers are connected.
any ideas?

Could be a few things mate;

1, Noise present with ign on but engine NOT running??? YES/NO
2, Does tone or pitch of noise alter in accordance to engine speed??? YES/NO
3, Do you have a Pioneer head unit??? YES/NO
4, Is noise present in all channels??? TWEETER/MID/SUB or ALL
5, Location of amp earth??? BOOT FLOOR/MOUNTING BOLT/REAR LIGHT CLUSTER EARTHING POINT
6, Are all items new???
7, Did you install everything yourself???


Simple test to locate fault;

System OFF
1, Remove RCA leads from amp---Switch system on & play as normal---Noise present = Amp or associated wiring issue, (most common is weak earth or speaker terminal shorting to door panel)......No noise present = Fault before amp stage......

System OFF
2, Plug RCA leads back into amp---Remove head unit from dash and remove RCA leads from head unit---Switch system on and play as normal---Noise present = RCA lead fault, replace leads......No noise indicates head unit or associated wiring fault......

Post up results for analysis......

 

[ash26ace]

ok thanks for replying guys.

first answers to seans questions-

do you have seperate amps for the sub n comps?
no i have a 4 channel amp running them both

where are you earths?
the earth is boot floor/mounting bolt

what equipment is it your using?
alpine head unit http://www.caraudiodirect.co.uk/alpine-cde9872r-p-6365.html
jbl sub- http://caraudiosecurity.com/shop/product/products_id/1923.html
jbl amp- http://www.caraudiodirect.co.uk/jbl-gto1004-p-6240.html
fusion speakers- http://www.caraudiodirect.co.uk/fusion-encounter-cm5250-p-6687.html

what HU?
http://www.caraudiodirect.co.uk/alpine-cde9872r-p-6365.html
what car?
clio 16v expression
by crackling, what do you mean?
the crackling is more of a buzzing when the engine is running




now wallops questions-

1, Noise present with ign on but engine NOT running??? when ignition is on the noise is more of a small crackle then when the engine us running its more of a buzz

2, Does tone or pitch of noise alter in accordance to engine speed??? YES the faster i go the more it whines

3, Do you have a Pioneer head unit??? NO its ALPINE

4, Is noise present in all channels??? TWEETERS AND FRONT

5, Location of amp earth??? BOOT FLOOR/MOUNTING BOLT

6, Are all items new??? YES

7, Did you install everything yourself??? JUST THE SPEAKERS NOT THE AMP AND SUB


i did the tests and there is only noise if both RCAS for the the sub and components are plugged in. its nothing wrong with the rcas because i went and bought some new ones (the best quality the had) and it made no difference

again thanks for your help

 

[wallop]

Noise with engine not running points to;

1, Speaker terminal shorting to the door skin.....
2, Speaker wire trapped or pinched again causing a short.....
3, Head unit earth track blown.....
4, Naff amp earth.....

Try running system with sub RCA leads fitted, but only one front RCA fitted, (f/right), if no noise then remove it and try the other RCA, (f/left).....

This should hopefully indicate which speaker is affected......If both sides induce noise individually then I would try relocating the amp earth.....

Don't under any circumstances remove or fit RCA leads with the system switched on......


Post results.....

 

[ash26ace]

right sorry it took ages to reply
i tried what you said with the left and right rca leads and both sides produce a noise individually so then i thought as you said the earth would be crap but its actually not where i thought it was originally and is located under the seat in a drilled hole. so still no luck there

what else could it be i have no idea?

 

[wallop]

right sorry it took ages to reply
i tried what you said with the left and right rca leads and both sides produce a noise individually so then i thought as you said the earth would be crap but its actually not where i thought it was originally and is located under the seat in a drilled hole. so still no luck there

what else could it be i have no idea?

With system OFF....
Remove the RCA leads from the head unit...Switch on & play as normal with engine running....

Noise still present indicates naff earth, Faulty RCA leads, or faulty amp/amp wiring....

No noise indicates faulty head unit or associated wiring.....(either damaged head unit earth track or poor head unit earthing).....

Some stock audio looms use common earthing points, when fitting new units these common earth sites can create an annoying 'ground loop', to avoid this you can simply bypass the stock audio looms earth, earth the unit direct to the cars chassis.....

When I fit Alpine units I tend to avoid using the stock Batt supply & Earth, I usually opt for a direct supply from the Battery fused at 15amps & direct to chassis earthing.....

There is a possibility its a blown 'Earth Track', check this Thread on another forum, POST 18...........

 

[ash26ace]

no there is no noise when i unplug the rcas from the head unit the noise is only there when both the speakers and the sub are plugged in

 

[MT AUDIO]

wheres your cables running?ie rcas and power cable?

 

[ash26ace]

down the side under the trim. yes they are on the same side if thats what you meant. but iv tried it when there not and i still get the buzzing sound

 

[ash26ace]

ok iv fixed it well sort of i think iv mostly reduced the problem but im happy with it because theres barely a noise now and it all sounds awesome. all i did was fit a ground loop insulator between the amp and the sub.

 

[kylemanchester]

Ive just got a clio & the same front comps, where have you put the green box thing for the comps?? Any pics???

Cheers bud!!

 

[ash26ace]

i mounted the crossovers under the front seats with some strong double sided tape (its quite discreet) i cant find my camera so i had to use my phone so sorry about the quality. i did think about mounting them under the glovebox but then i remembered your supposed to mount them close to the speakers and i mounted the tweeters on my doors because i couldn't be bothered to take off my dash.