Thumping through subs when it feels like it

[vn_wagon90]

Hey all .. I have 2 x 12 earthquakes the old school type .. Now i have them disconnected due to a trip to QLD and kids stuff needing my boot .. i went to put them in and not if i hook one on its ok but sounds crap, If i plug both in it starts thumping randomly at will, it doesnt matter which one i plug in first, it still does it .. I am using a US Audio 600w max output 1 x 240w @ 14.4 v or 1 x 200 w @ 9.4v (yes its **** .. but its been a great amp so far) i have turned all the gain and everything down and just set it for a bass back up, (so u can just hear it) and ideas why it could be doing this, it has never done it before and i was told 15 differnet stories by Autobarn and i really dont care to much for what they have to say!

 

[acarmody]

The reason you got 15 different answers at Autobarn is because you found 15 different idiots.

First off, if you plug the subs in and disconnect the input to the amp does it still make noise.

 

[vn_wagon90]

LMFAO .. I was being nice .. But yes you are right, yes it does stop .. But i have noticed another thing .. it might be helpfull. I have an idoit gauge, cause i was having dramas when i first installed it, that tells me the volts that the amp is getting .. When it thumps it goes from 13.8 - 14.0v (car runnning) to 12.5 - 12.8v when there car is off ign on, it goes from 13.2v to 11.8 - "Lo". Does that make any difference to the answer of what it could be ?

 

[acarmody]

I'm thinking that the problem isn't the amps or sub but the source, but maybe not.

When you say you hooked one sub up but it sounded crap, did you have the amp set to LPF about 80-100hz?

And how did you wire them up when you hooked both subs up? Diagram would be good?

 

[vn_wagon90]

I just relised i havent given all the info mate .. the amp is a mono block amp there is no HPF or LPF switch.. it is set on Z BASS @ 8DB and the the other dial is set at about 95DB. When i hook just either one of the subs up to the amp + on + and - on - , the bass is low and sounds destorted it i go + on - and + on - it sounds worse .. So the wires are right when it is POS on POS and NEG on NEG .. What i will do is Upload some pic 2 morrow arvo of the subs and amp and see what you can come up with

 

[acarmody]

Yeah photos would be great, especially of the amp ends since I have never heard of those settings before.

Also if you get a chance try and find another source to drive the amp. Another H/U or something. Even just getting a mates car parked next to yours and just running the RCAs from one car to the other.

 

[vn_wagon90]

Sorry it has taken me time to do it. .I have been flat out .. But here are the pics of the amp and subs abd voltmeter

 

[acarmody]

Got any bigger pictures?

 

[vn_wagon90]

How can i make them bigger .. There just off the phone, they have been bigger on my facebook pics, and my desktop, Just not here

 

[acarmody]

Go to your facebook page, right click on the images, get the direct url for them (In firefox its right-click 'copy image location') in the post reply page here there is a button called insert image, click that, insert image url, and done, rinse and repeat for each image.