WANTED: Amp for a Sub

[Courior]

my amp is a Radio Mobile RA400 MOSFET 2 channel amp... £9 off ebay a year ago.. its been amazing so far but now a red light thats labelled "PROT" has come on and the sub just makes a faint drum beat noise every 2 secs... i have removed it and replaced thinking this would reset something? and its screwed... but im not too fussed it was only £9...

so anyone got a replacement amp?? i have NO idea what sub i have.. it was second hand off ebay for £10 (i wanted just the box but the sub sounded great so i used it). its well enough to shake windows, seats, the whole car basically. the old amp was 400W so i imagine the sub to be about the same.. really i dont know. but as long as the amp will power a 12" sub to reasonable levels, and accept a bog standard RCA input then i would like to take it off your hands

 

[Noddie]

'Prot' stands for protection. im not much good at ICE but as i see it its the amps way of protecting itself if there is somthing wrong with the wiring, check see if the fuse in the amp has gone. and check all wiring. my mate has a JL amp and two 10in JL subs that he lent me because this happened to him, so i said i would try them in my car to see if i could get them working (have now taken them out because my ears were complaining) i would see if you can fix it before you chuck it out.
Ed

 

[Retepetsir]

The sub might be toasted, use a multimeter to check the resistance of the subwoofer, if its very low (i.e. below 1ohm) then its shorting = boogered. If its very high (i.e. 50ohms or above) then its a toasted voicecoil/dodgy tinsel lead....new sub time!

So check the sub first

 

[Courior]

It still has the problem if i remove the input sound signal and the output to the sub. i havent checked the 2 fuses on the amp yet. thats number 1 thing to do 2moro... if no one has one im gonna get a 200W RMS one from maplins for £40,, some cheapo make but dont care as long as it has low pass filter, im not in it to win any comps.

 

[Retepetsir]

It still has the problem if i remove the input sound signal and the output to the sub. i havent checked the 2 fuses on the amp yet. thats number 1 thing to do 2moro... if no one has one im gonna get a 200W RMS one from maplins for £40,, some cheapo make but dont care as long as it has low pass filter, im not in it to win any comps.

Rather than spend £40 on that, get a second hand amp from Ebay

 

[Courior]

well.. got the 200W amp from maplins, wired it up and it worked great.. untill 1/2 volume.. then it would go into protection mode! ###### i thought.. so i looked around on the net and found that if the sub is a lot more powerful than the amp then the amp would go into protect mode so it wouldnt burn out trying to power something it just couldnt. i got the serial number off my sub and found its a Eminence Limited Edition 12" 500W RMS Sub.. so made sense the amp was protecting itself.. went to halfrauds and got a 200W RMS mutant sub at 12" and it workes perfectly with my 200W amp all the way to full power! .. so there is nothing wrong with the old sub speaker.

This also explains the old amp dieing! the old amp was 400W and the sub was 500W so it was workin its ass off and eventually burnt out trying to power something too much for it.

overall though its now much deeper bass and looks much nicer than the old sub! well chuffed!

 

[curtis]

it doesn't matter if the sub is more than what the amp is output power....the sub will run at what ever the amp outputs therefore the amp will work the same regardless of the subs wattage. some people run subs from there cd player unit....but i don't recommend this lol

If it cuts out after a certian amount of volume, it could just be a bad earth!

 

[Retepetsir]

Nope its not at all because its more powerful.

Like I suggested before....its most likely the sub that has a problem!

Take the amp back and spend a fiver on a multimeter.

Oh and Eminence old school subs are seriously nice ones, I hope it isnt fried . You can booger the sub by driving the amp into producing a clipped output = toasty voicecoils.

Would be nice if you could check the resistance of the voicecoil, just to see if its ok or not

 

[Courior]

well the reason for my theory was my uncle ran an extra 2 6X9's wired into his existing rear speakers and as soon as he did this the HU would turn off when the volume got loud.. so it was like there was too many speakers to power.. its now running up to full blast into distortion without cutting off so my wiring is ok. how do i check the voice coil?? i have a all singing and dancing multimeter and no idea how to use it except to find live lol!!