2005 VZ EXEC
Subs cut out... think it might be the battery
hey guys heres the system im running...
Alpine CDA-9884E Headunit
MB Quart Splits
MB Quart 2-ways
Alpine 600w 4CH Amp
Alpine 1000w Monoblock
2 Alpine 12" Type R Subs
the history:
my problem is that ill be driving with my music up and the subs will cut out for about 5 seconds then come back on (particularly in high bass songs), then continue to do so every 10 seconds or so. its just strange because it is doing it on songs that it never did it on before, i asked a guy in a sound shop and because i had both amps grounded together he said seperate them, i did that and still didnt help (sanded back paint etc to ensure good ground connection), i turned the gain down a bit and it takes longer for them to cut out... but it still does it.
my findings:
tonight i parked up and got my meter out n put it across the incoming + and - terminals on the amp, it sits at a steady 13v or so and then drops to about 6v when the sound cuts out then quickly goes up to 14v before the music turns on.
ive had the issue of lights dimmin since i bought it, and i understand why this happens, my question is basically will a power cap fix the problem with my subs cutting out? or is it more likely to be a battery issue? i was thinkin of gettin the power cap anyways as it will rectify my issue with the dimming lights, and if that doesnt fix it then look into gettin a new battery, anyone got any other suggestions on what else i can do to help define my issue.
//There Ain't No Rest For The Wicked...
What gauge power/ground wire are you running?!?
Originally Posted by garth
2005 VZ EXEC
not too sure, it looks about the equivelant of 6mm2 flex (if you know what that looks like) i THINK its 4 guage tho.
EDIT: i just looked up a conversion rate and it says 4 guage is around 21mm2, which my cable certainly doesnt look like,
i dont know a thing about AWG sizes, but if i go on the fact it looks around 6mm2 i would have to says its 9 or 10 guage then.
i can find out tomorrow what size it is as ill ask the guy who picked out all my cable sizes for me.
Car Audio Installer
the voltage is the reason the subs are cuttting out. The amplifier is turning off as the voltage drops below 9 10 volts. Its impossible to say exactly why this is happening without looking at the car. But i would suggest a worn battery and or alternator or possible a worn fuse on your power wire. Doing a load test on the battery is the first check i would do then replacing your fuse and doing a check on the alternator.
If you had a short or overload or thermal (heat) issue with the amplifier then it would go into protection but as it is not doing that its safe to assume the subs are ok. Although again the amplifier could still be faulty and your earths as you mentioned b4 have been checked which can cause this drop in voltage as the amount of current attempts to return to earth.
If your battery and alternator and wiring are ok as well as your power wire fuse then there should be no reason the voltage should drop down to 6 volts.
2005 VZ EXEC
okay, is it easy to test a battery? is it something i can do myself or would i need to take it into an auto sparky?
Car Audio Installer
doing a load test on a battery is done by an expensive device that you connect to a battery and it has a big dial on it that you wind up which tests the cold cranking amps performance of the battery. Cold cranking amps that a battery is rated at is its twisting or turning ouput capabilty or in other words the batterys torque. I may be corrected on my description somewhat but thats the understanding which helps me to explain what a proper load test is. As the current is increased the voltage drops. If you drop in to an auto elec and ask nicely early in the morning, you may get them to do one for you quickly for free.
2005 VZ EXEC
no dramas, thanks for your help champ, will do that tomorrow morning... thank **** for RDO's haha, ill post update tomorrow evening, cheers.
//There Ain't No Rest For The Wicked...
Mate if your cables undersized thats your issue, not battery...
2005 VZ EXEC
yeh ill find out what size it is and post up tomorrow... if the cable was undersized it would be warm tho wouldnt it? coz it never gets warm
Car Audio Installer
Yes your right, 6mm2 wire i think is about 10 awg, which is too small which is why your voltage is dropping.
I work with a w g wire sizes but found this and if it is 6mm2 wire size then definatly the reason your voltage is dropping.
AWG to Metric Conversion Chart
2005 VZ EXEC
just had a look this morning, my cable is only 8 guage... from what ive read around the forum that seems too small to me.. would that be right?
got my battery load tested and they said its fine, im getting a 1 farad power cap of a guy at work for $50, but by the the looks of it i might be in for a re-wire eh?
TURN MY HEADPHONES UP
8 gauge is way too small. i run 8 gauge to a 300wRMS monoblock (that's all i have in the boot), and i was a bit iffy about that...
you'd be wanting to run 4 gauge minimum, i had a similar setup in my last car and from memory i had a 2 gauge power cable to a distribution block in the boot, which ran 8g each to three amps. you might want 8g to 4ch, and 4g to monoblock (see if it will take a 4g cable or not, that's a good indication of what you should be running). that might be overkill though, 4g main and 8g to each amp is probably enough. it's been a long time
2005 VZ EXEC
i have 2 seperate runs for each amp, both in 8 guag (should have mentioned that earlier) so effectively thats the same as runnin a 4 guage main and splitting it into 8 guage's, spoke to the guy at alberts car stereo n he said my cable should be fine, but, im still taking all your suggestions into consideration, sometimes the guys at places like that dont even know that much lol.8 gauge is way too small. i run 8 gauge to a 300wRMS monoblock (that's all i have in the boot), and i was a bit iffy about that...
you'd be wanting to run 4 gauge minimum, i had a similar setup in my last car and from memory i had a 2 gauge power cable to a distribution block in the boot, which ran 8g each to three amps. you might want 8g to 4ch, and 4g to monoblock (see if it will take a 4g cable or not, that's a good indication of what you should be running). that might be overkill though, 4g main and 8g to each amp is probably enough. it's been a long time
he also suggested it might be a good idea to change the configuration of the subbs, at the moment they are wired up in series/parallel (dual voice coil, so the voice coils are in series and both subs are in parallel with each other) which would be giving me 2 ohms, he said it might be an idea to change it to series/series, which would give me 8 ohms, what are your opinions on that?
i think the way i might go is to try the power capacitor first and see if that helps, if it doesnt help atleast itll be able to help with the lights dimming lol.
i also got my battery and alternator tested this morning, they said its all good.
Have you upgraded your earth cable from battery to car? basically just run 4 gauge or so cable from negative to ur chassis in the engine bay.
This is mine
http://home.people.net.au/~darknes/29112008528.jpg
2005 VZ EXEC
that link didnt work mate, but thats a good point, i'll do that for sure!
2005 VZ EXEC
good stuff mate, did you just use lugs, i think i'll grab a bit of 95mm2 welding earth from work and use that.
yeh, soldered the lugs on, from memory, think i had to drill one of the lug holes a bit bigger to fit one of the bolts on, not sure though.
TURN MY HEADPHONES UP
8g to each amp should be ok then, as you said, it won't make a difference if you split a 4g into 8g at the end anyway. for anyone interested, 4g almost has the same amount of area as 3x8gs, so you can run 3 amps off a single 4g cable provided that 8g is the maximum cable size they will take. i was probably wrong in my last comment, i bet my last car had a 4g main power cable running to the boot.
do you have the model number for your subs? type r's come in 2ohm per coil or 4ohm per coil. if you have the 2ohm ones, then that sounds about right. however if you have the 4ohm ones, then you'll already be running a 4ohm load, and you don't really need to go higher than that. you don't typically hear people running their amps with an 8ohm load, so i wouldn't recommend doing it as there is another problem here that should be fixed
2005 VZ EXEC
no worries, ill just use my tradesmans hydrualic crimpers, thanks mate.
no worries, thanks for that. ill start by upgrading the main ground cable and wacking a power cap into the circuit and see how i go, wont be doing that till wednesday tho so i'lll post up my findings then, thanks for your help guys.8g to each amp should be ok then, as you said, it won't make a difference if you split a 4g into 8g at the end anyway. for anyone interested, 4g almost has the same amount of area as 3x8gs, so you can run 3 amps off a single 4g cable provided that 8g is the maximum cable size they will take. i was probably wrong in my last comment, i bet my last car had a 4g main power cable running to the boot.
do you have the model number for your subs? type r's come in 2ohm per coil or 4ohm per coil. if you have the 2ohm ones, then that sounds about right. however if you have the 4ohm ones, then you'll already be running a 4ohm load, and you don't really need to go higher than that. you don't typically hear people running their amps with an 8ohm load, so i wouldn't recommend doing it as there is another problem here that should be fixed
Donati..Whoa Green
An audio place told you to take you subs down to 8ohms! What? You would get piss all power from those subs!
Something you can try till you get larger cable. Get the two 8g power cables and put them into a distribution block and then run 8g to the 4-channel amp and 4g to the mono. The mono is going to draw more power then the 4-channel, so when a bass note hits it can use its 8g cable and say half of the other 8g cable. Temp idea only, larger cable is definately better.
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2005 VZ EXEC
fixed my problem, my mate who did the wiring (i gave him a hand) selected 50A cb's for each amp, put a clamp meter on the 8awg going to the subs and it was drawing 70A lol, so the CB was trippin and reseting itself, im an apprentice electrician so im not used to CB's resetting themselves so i didnt even think of it lol, but upgraded it to an 80A fuse, which is slightly more than what 8awg is rated for so im plannin on upgrading the cable to 4awg in the near future, but for not im happy coz everything works as its supposed to, its good to be able to listen to music without my subs constantly cutting out.
thanks to everyone for your input and advice and hopefully this thread proves usefull in future.
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