Hi all,

Recently got my sub (LONG overdue) and plugged it into my amp (JBL 75.4 - info) how they suggested in the book, and the sub worked but my components didnt.

The way its set up at the moment is that the front components run off the channels that say "rear" on their own. So i moved them to "front" and wired the sub to the "rear" and they stopped working, but the sub worked.

So I changed it again and put the sub on the "front" and the components on the "rear" (how they were originally) but this time the sub didnt work.

Does this mean my 4 channel amp has only 2 channels working properly? And is there anyway to fix this? It's not too much of a problem cos I've bought another amp too so I can power the sub off that, but its besides the point, and plus I could be running the sub now, as I've not wired the other amp yet.

Help muchly appreciated

Tom

Edited 15 September, 200719 yr by Tom7

Hi all,

Recently got my sub (LONG overdue) and plugged it into my amp (JBL 75.4 - info) how they suggested in the book, and the sub worked but my components didnt.

The way its set up at the moment is that the front components run off the channels that say "rear" on their own. So i moved them to "front" and wired the sub to the "rear" and they stopped working, but the sub worked.

So I changed it again and put the sub on the "front" and the components on the "rear" (how they were originally) but this time the sub didnt work.

Does this mean my 4 channel amp has only 2 channels working properly? And is there anyway to fix this? It's not too much of a problem cos I've bought another amp too so I can power the sub off that, but its besides the point, and plus I could be running the sub now, as I've not wired the other amp yet.

Help muchly appreciated

Tom

Have you checked on the headunit that the balance isnt set on 100%forward?

yea, and i changed it to "defeat on" but it didnt like that and turned the sub off lol!!

have you got splitters for rca going to amp to make the rca lead into 4 plugs

and it should work check the gain control on amp channel and see it is set low

is there any chance mate i could see a pic how you have wired it in mate so i could see if any wiring error

sounds to me like you have only got rca input leads on two of the 4 i/p channels on the amp

yea sorry guys not much help without pics is it, ill get some up asap

Hi guys,

Here's some pics, sorry there not brilliant. Any help would be great, but I'm gona have to take it out the car now anyways thanks to the crash, but at least I'll know how to do it when I get it back

need pics of the other end of the amp to be certain, but it sounds like you need a pair of splitters llike these:

http://cgi.ebay.co.uk/PHONO-RCA-2M-1FM-GOL...VQQcmdZViewItem

the buy now price is for 1 so you will need to order 2.

make sure you get the ones that go from 1 female to 2 males.

page not responding mate, how come it wont work when i try n bridge it tho?

And how come i can only get either bits to work on the rear part?

take a pic of the other end of the amp.if you have only two rcas plugged into the i/ps then thats the prob cos you will need 4.

yea your right, i just checked, there is only 1 set of rca's in......feel well stupid......so where does this plug into on to the sub though? cos theres only the two gold terminals on the sub box which plug into the amp.......do i need some adapters or splitters liek grant said??

yea your right, i just checked, there is only 1 set of rca's in......feel well stupid......so where does this plug into on to the sub though? cos theres only the two gold terminals on the sub box which plug into the amp.......do i need some adapters or splitters liek grant said??

right, from the pic it looks like you have the components wired up fine. you need to screw the wires from the sub in to the far left and far right of the screws underneath (so miss the two screws in the midle out so it is bridged).

then the phono lead that comes out of the back of the cd player needs to pe pluged into the phono sockets in the amp, you need to split this wire (using splitters). put 1 spliter on each side of the wire so that you end up with four instead of two. once this is done to plug them in to all four phono sockets on the amp with one red and one white in each channel (so you have left and right connected to both channels).

that should do it, hope this makes sense.

yea your right, i just checked, there is only 1 set of rca's in......feel well stupid......so where does this plug into on to the sub though? cos theres only the two gold terminals on the sub box which plug into the amp.......do i need some adapters or splitters liek grant said??

right, from the pic it looks like you have the components wired up fine. you need to screw the wires from the sub in to the far left and far right of the screws underneath (so miss the two screws in the midle out so it is bridged).

then the phono lead that comes out of the back of the cd player needs to pe pluged into the phono sockets in the amp, you need to split this wire (using splitters). put 1 spliter on each side of the wire so that you end up with four instead of two. once this is done to plug them in to all four phono sockets on the amp with one red and one white in each channel (so you have left and right connected to both channels).

that should do it, hope this makes sense.

http://www.bassjunkies.com/?pid=32517&...p;source=search

heres another link hope it works. if it does buy two and I'm sure you will work it out. can get them cheaper on ebay though.

thanks for that mate, kinda makes sense now, gona be a pain to my headunit out cos of the amount of cables behind it, but ill have a go....r they sumthin i can buy from halfords? cos i could go get them tomorrow if so...

thanks for that mate, kinda makes sense now, gona be a pain to my headunit out cos of the amount of cables behind it, but ill have a go....r they sumthin i can buy from halfords? cos i could go get them tomorrow if so...

you dont need to take the head unit out. yes you can get them from halfords.

excellent mate cheers sorry i kinda figured that out after i thought about it lol

Thanks to everyone for your help