strange amp problem

[bengie]

i changed my subs today for bigger more powerfull ones and its also running at 1ohm now.

my amp is 1ohm stable but if i turn it up quite loud it doesn't ditort at all but it will cut out(just the subs). now my amp has all sorts of built in protection including undervoltage, could it be that seeing as i am now running 2x300WRMS DVC subs as oppose to 2x200W RMS SVC subs they are taking a bigger chunk of power when turned up and as a consequnce the voltage is dipping slightly do the amp cuts itself out to protect itself

i have a 1 fahrad cap on it but tbh i don't think its worked since it got shorted by mistake a tear or so ago

[devonutopia]

Cutting out might be the earth mate. I had that when using a dodgy point. I moved it to a better place, and now it doesn't cut out however loud it goes.

Ultimate earth is screw straight into the chassis somewhere (like boot floor), and then vaseline over the top to prevent corrosion and cr4p getting in.

Check the earth though! Sounds like the most guilty suspect to me.

[bengie]

cheers J, my earth is all right but top super duper uber solid. maybe i need to look at this in the daylight

[devonutopia]

Originally Posted by bengie

cheers J, my earth is all right but top super duper uber solid. maybe i need to look at this in the daylight

I thought mine was really solid too, but it turned out to be a lot of non conductable material in the mount (used part of boot catch)

Now I use one of the bolts for the rear cluster, which is much better, but still not A1 (not running the sort of power to test it yet - might be soon though when my US import arrives )

[bengie]

bit of a typo there in my post, supposed to say it's all right but not super duper uber solid

my screw up but cheers for the advice, i'll try other places in the daylight

[Matt_vRS]

Your amp may be 1 ohm stable but some manufacturers say that they are "stable" at 1 Ohm when in actual fact they aren't really supposed to drive at 1 ohm - they just won't blow up!!! What amp is it?

I am guessing you have the DVC subs with the VCs in parrallel (2 x 4ohm VC = 2 ohm) and then you have the two subs in parrallel as well making the 1 ohm load? What subs are they?

[Matt_vRS]

Also remove the cap - that will reduce the voltage to your amp anyway.

[bengie]

i have a directed 600D and running 2x alpine 12" type S

[bpm]

You best bet is to stick a multimeter on every point to compare the voltage levels. It should give some indication of where the issue may lie.

[bengie]

been playing today and the subs are at 1ohm as they should be, the voltage is hovering around 13 - 13.5 then dropping to mid 12 on heavy bass lines but we think it may be due to temperature so i am gonna stick so 12v fans in my under floor setup. hopefully this will sort it.

[bengie]

been playing with this today and took the floor up in the boot to expose the amps and repositioned the subs so that they still work, the stereo does nothing but thump like this and never cut out once.

so it looks like the problem i'm having is my amp over heating, the easiest solution for me is to reposition the amp so that it gets more air circulating around it.

oh, yet more wood into the car to make a support for the amp