Audio and Electronics Discuss in-car entertainment systems, audio and video systems, car alarms and other electronics topics.

Amp Blowing fuses

Thread Tools
 
Search this Thread
 
Old 05-28-2009 | 08:40 AM
  #1  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Amp Blowing fuses

Im somewhat of a noob when it comes to car audio but i have a cheap 1000 watt interfire 2 channel amp that ive had for about 2 years now, and a recently installed 12" kicker CVX. I had 2 12" kicker comps installed, one sub per channel. When i hooked up my cvx i put it into bridged mode. It started to play just fine, but i went to turn up the head unit and the fuses blew. theyre 20amp rated fuses and im POSITIVE that all my power and grounding wiring is alright because the prior comp setup ran like a champ. any ideas?
Old 05-28-2009 | 10:04 AM
  #2  
djfrestyl's Avatar
Suspension Yoda
iTrader: (89)
 
Joined: Aug 2003
Posts: 13,501
From: Central, NJ
The fuses on the amp? Are you sure you wired the subs correctly with the right impedance?

http://www.crutchfield.com/S-crzddPP...rs_wiring.html
Old 05-28-2009 | 10:16 AM
  #3  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by djfrestyl
The fuses on the amp? Are you sure you wired the subs correctly with the right impedance?

http://www.crutchfield.com/S-crzddPP...rs_wiring.html


yea, the amp fuses blew. i didnt do the wiring on the sub myself, it was a loaded enclosure so it could be that but it said it was ready for a 2 or 4 ohm load. when the amp is bridged is it not a 2 or 4 ohm load?
Old 05-28-2009 | 10:18 AM
  #4  
djfrestyl's Avatar
Suspension Yoda
iTrader: (89)
 
Joined: Aug 2003
Posts: 13,501
From: Central, NJ
"Ready for a 2 or 4ohm load" - no such thing. It's either 2 or 4, and that needs to be identified so that you can properly wire it in accordance to the specs of the amp.
Old 05-28-2009 | 10:24 AM
  #5  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by djfrestyl
"Ready for a 2 or 4ohm load" - no such thing. It's either 2 or 4, and that needs to be identified so that you can properly wire it in accordance to the specs of the amp.

fair enough, well lemme pop the sub out of the box and see how its wired.
Old 05-28-2009 | 11:33 AM
  #6  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
the subwoofer is wired for 2ohm, i replaced the fuses and im running the cvx on only one channel instead of bridged but id rather it be bridged.
Old 05-28-2009 | 11:50 AM
  #7  
importcf's Avatar
Member
 
Joined: Mar 2009
Posts: 254
From: Belmont, MA
the amp might not be able to go down to 2 ohm. is it DVC (Dual voice coil). ide also check your ground and maybe even make sure the right fuse is in the amp.
Old 05-28-2009 | 12:42 PM
  #8  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by importcf
the amp might not be able to go down to 2 ohm. is it DVC (Dual voice coil). ide also check your ground and maybe even make sure the right fuse is in the amp.

it is dual voice coil and the ground is perfect. im not sure which type of fuse is supposed to go in. the amp is an older model so its not on the manufacturers website so i cant check which fuse is supposed to work. i have 2 20amp fuses in it currently but i called the local audio shop that carries it and he says that it can handle 2 30 amp fuses but im scared to put them in because im not trying to blow up anything lol
Old 05-28-2009 | 12:54 PM
  #9  
djfrestyl's Avatar
Suspension Yoda
iTrader: (89)
 
Joined: Aug 2003
Posts: 13,501
From: Central, NJ
Dual voice coil - and each coil is how many ohm? I'd take a look at the Crutchfield link, and I'd DEFINITELY open up that box to see how the sub itself is wired.
Old 05-28-2009 | 01:44 PM
  #10  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by djfrestyl
Dual voice coil - and each coil is how many ohm? I'd take a look at the Crutchfield link, and I'd DEFINITELY open up that box to see how the sub itself is wired.

im not sure how many ohms per coil and i cant really make sense of the crutchfield link because the 2 channel bridged pictures are the same no matter the ohm rating
Old 05-28-2009 | 04:00 PM
  #11  
importcf's Avatar
Member
 
Joined: Mar 2009
Posts: 254
From: Belmont, MA
how bout some sub model numbers and amp model numbers that should help. ide check the wiring of the voice coil wiring 1st and then possibly change fuses 20amp seems low but i might be wrong. these fuses are on the amp correct not on the power wire? what gauge wire for power and ground? what are you grounded to? just fig ide ask all this so we can eliminate any possible problems
Old 05-28-2009 | 04:09 PM
  #12  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by importcf
how bout some sub model numbers and amp model numbers that should help. ide check the wiring of the voice coil wiring 1st and then possibly change fuses 20amp seems low but i might be wrong. these fuses are on the amp correct not on the power wire? what gauge wire for power and ground? what are you grounded to? just fig ide ask all this so we can eliminate any possible problems

i thought 20amp fuses seemed low, and yes the fuses are on the amp, not the power line. i dont remember what gauge wire but its about the thickness of the face of a penny. im grounded properly and all the wires power and ground wires are installed correctly, remember i had a system prior to this that was NOT bridged. i had 2 kicker comps (one on each channel).

here's the sub
http://kicker.com/comp_vx

and for the amp...uuuh about that lol. i cant find anything ANYWHERE about this amplifier. this is the newer model of my amp, but not the amp i have.

http://interfireaudio.com/ampsAB.html (its the 2.1000 one)
Old 05-28-2009 | 04:23 PM
  #13  
importcf's Avatar
Member
 
Joined: Mar 2009
Posts: 254
From: Belmont, MA
sounds like 0ga. ok so looks like the new model goes down to 4ohms stable. these subs come with either 4ohm voice coils or 2ohm and this is kinda key for setting up the wiring. you very well could be dipping too low for this amp see if u can get a full model number like my JL is 10w3 d6 for dual 6 ohm voice coils. let me know and i can show you how to wire up for a 4 ohm load if it isnt already that way. I am also assuming the wouldnt lower the handling cababilities on the new model
Old 05-28-2009 | 04:55 PM
  #14  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by importcf
sounds like 0ga. ok so looks like the new model goes down to 4ohms stable. these subs come with either 4ohm voice coils or 2ohm and this is kinda key for setting up the wiring. you very well could be dipping too low for this amp see if u can get a full model number like my JL is 10w3 d6 for dual 6 ohm voice coils. let me know and i can show you how to wire up for a 4 ohm load if it isnt already that way. I am also assuming the wouldnt lower the handling cababilities on the new model

ok sounds good, ill have to do it tomorrow though because i have to go in for work. first thing in the morning. thanks for all your help
Old 05-28-2009 | 07:20 PM
  #15  
djfrestyl's Avatar
Suspension Yoda
iTrader: (89)
 
Joined: Aug 2003
Posts: 13,501
From: Central, NJ
Originally Posted by ryan_green1337
im not sure how many ohms per coil and i cant really make sense of the crutchfield link because the 2 channel bridged pictures are the same no matter the ohm rating
Then you're not reading it right. It tells you how to wire the sub to achieve the correct impedance, not which terminals to connect to the amp. You have to determine how low your amp can go, and then pick the right setup of the SUB to get there.
Old 05-29-2009 | 11:15 AM
  #16  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by djfrestyl
Then you're not reading it right. It tells you how to wire the sub to achieve the correct impedance, not which terminals to connect to the amp. You have to determine how low your amp can go, and then pick the right setup of the SUB to get there.

ok so i took the sub out of the enclosure today and saw that the two negative terminals were connected together and the positive coils were connected together. thats the best i can describe it, sorry if its difficult to understand
Old 05-29-2009 | 11:28 AM
  #17  
Calcvictim's Avatar
Member
 
Joined: May 2009
Posts: 133
From: pǝq s,ɐɯɯoɯ ɹnoʎ uı
Originally Posted by ryan_green1337
ok so i took the sub out of the enclosure today and saw that the two negative terminals were connected together and the positive coils were connected together. thats the best i can describe it, sorry if its difficult to understand
if the positive and the negative are connected together that means it's wired in parallel

1)figure out what is the impedance of each coil, should be on the sub itself
2)divide the impedance by half because the 2 coils are wired in parallel
for example if each coil is 4ohm, the resulting impedance of the sub as a whole the way it's wired is 2 ohm
3)find out if the total impedance is less then what the amp is stable at, most amps should be able to handle 2 ohm loads but probably not 1 ohm loads

4)bridging is done when you have 2 amplifiers powering the same speakers, what it effectively does is make both act as a single amp and the power of both is combined(Captain Planet baby)

because you only have one amplifier no bridging should be happening
Old 05-29-2009 | 11:28 AM
  #18  
djfrestyl's Avatar
Suspension Yoda
iTrader: (89)
 
Joined: Aug 2003
Posts: 13,501
From: Central, NJ
Do you own a multimeter? Need to know what impedance each of the voice coils are on the sub. You're making this overly complicated.
Old 05-29-2009 | 11:31 AM
  #19  
djfrestyl's Avatar
Suspension Yoda
iTrader: (89)
 
Joined: Aug 2003
Posts: 13,501
From: Central, NJ
Based on your info, you're using one of the two configurations:
http://akamaipix.crutchfield.com/ca/...4-ohm_mono.jpg
http://akamaipix.crutchfield.com/ca/...2-ohm_mono.jpg

All we need to know is the impedance of the voice coils.
Old 05-29-2009 | 11:33 AM
  #20  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by djfrestyl
Do you own a multimeter? Need to know what impedance each of the voice coils are on the sub. You're making this overly complicated.

its 2 ohm impedance
Old 05-29-2009 | 11:34 AM
  #21  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by djfrestyl
Based on your info, you're using one of the two configurations:
http://akamaipix.crutchfield.com/ca/...4-ohm_mono.jpg
http://akamaipix.crutchfield.com/ca/...2-ohm_mono.jpg

All we need to know is the impedance of the voice coils.
its 2 ohm and wired like the first link
Old 05-29-2009 | 11:35 AM
  #22  
Calcvictim's Avatar
Member
 
Joined: May 2009
Posts: 133
From: pǝq s,ɐɯɯoɯ ɹnoʎ uı
ok, what is your amp specs, is it a single channel or a 2 channel amp
Old 05-29-2009 | 11:36 AM
  #23  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by Calcvictim
ok, what is your amp specs, is it a single channel or a 2 channel amp
2 channel
Old 05-29-2009 | 11:50 AM
  #24  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by ryan_green1337
2 channel
i was told if i plugged the subwoofer into the 2 outer speaker ports on the amp that it would "bridge" the amp and put the full power of the amp into the one subwoofer. is this correct or bs?
Old 05-29-2009 | 11:59 AM
  #25  
Calcvictim's Avatar
Member
 
Joined: May 2009
Posts: 133
From: pǝq s,ɐɯɯoɯ ɹnoʎ uı
Originally Posted by ryan_green1337
2 channel
Originally Posted by ryan_green1337
i was told if i plugged the subwoofer into the 2 outer speaker ports on the amp that it would "bridge" the amp and put the full power of the amp into the one subwoofer. is this correct or bs?
it looks like you have an amp similar to this one, everything I say will rely on these specs
http://www.interfireaudio.com/ampsHighCurrent.html

1)the amp is not bridgeable running in 1 ohm(which is what your sub is wired to be)
2)it does work in 1 ohm mono, which means you should be able to connect it to your sub fine

3)un-bridge the amp and it should work fine



the way to bridge an amp is to connect one channel positive to the second channel negative and use the unocupied terminal for the speaker/sub
Old 05-29-2009 | 01:50 PM
  #26  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by Calcvictim
it looks like you have an amp similar to this one, everything I say will rely on these specs
http://www.interfireaudio.com/ampsHighCurrent.html

1)the amp is not bridgeable running in 1 ohm(which is what your sub is wired to be)
2)it does work in 1 ohm mono, which means you should be able to connect it to your sub fine

3)un-bridge the amp and it should work fine



the way to bridge an amp is to connect one channel positive to the second channel negative and use the unocupied terminal for the speaker/sub

ya i have it unbridged right now, is there a way that i can wire my subwoofer in a way so i can hook it up to my amp bridged?
Old 05-29-2009 | 02:01 PM
  #27  
importcf's Avatar
Member
 
Joined: Mar 2009
Posts: 254
From: Belmont, MA
your amp is not stable at one ohm so u need a new sub or an amp there kinda not computable. you can prob run it but it will beat on the amp
Old 05-29-2009 | 02:03 PM
  #28  
importcf's Avatar
Member
 
Joined: Mar 2009
Posts: 254
From: Belmont, MA
try to wire like this http://akamaipix.crutchfield.com/ca/...2-ohm_mono.jpg then bridge
Old 05-29-2009 | 02:24 PM
  #29  
Calcvictim's Avatar
Member
 
Joined: May 2009
Posts: 133
From: pǝq s,ɐɯɯoɯ ɹnoʎ uı
Originally Posted by importcf
he will lose power if he wires it that way, if his amp is 2 ohm stable which it is it doesn't make sense to wire it into 4 ohms



I am guessing you want the most power out of the sub, if that is the case then you want to wire each coil seperately to each one of the channels

looking at the specs on the website you can wire the sub and amp 2 ways

way 1)2 coils are wired in series as importcf suggested, resulting in your sub having one 4 ohm load, then you can bridge the 2 channels and in result you have 250 watts of power
way 2)seperately wire each coil to each channel and you have 2 2ohm loads, which give you 2 channels at 200 watts each


I would choose way2

Last edited by Calcvictim; 05-29-2009 at 02:26 PM.
Old 05-29-2009 | 03:56 PM
  #30  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by importcf
your amp is not stable at one ohm so u need a new sub or an amp there kinda not computable. you can prob run it but it will beat on the amp

well the amp is old anyways so i was planning on replacing that anyways. so all i need is a mono amp that can handle a 1ohm load?
Old 05-29-2009 | 04:11 PM
  #31  
djfrestyl's Avatar
Suspension Yoda
iTrader: (89)
 
Joined: Aug 2003
Posts: 13,501
From: Central, NJ
Yep. You have dual 2ohm VC's, so you can wire it down to 1ohm.
Old 05-29-2009 | 09:47 PM
  #32  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by djfrestyl
Yep. You have dual 2ohm VC's, so you can wire it down to 1ohm.

sweet, thanks for all your help guys. definately learned a lot. sorry im such a slow learner. does anyone have a recommendation for an amp? no more than 750 watt rms and has to be able to handle a 1ohm load. not sure what my budget is but im not trying to fork over a leg or anything.
Old 05-29-2009 | 10:41 PM
  #33  
Calcvictim's Avatar
Member
 
Joined: May 2009
Posts: 133
From: pǝq s,ɐɯɯoɯ ɹnoʎ uı
just my opinion but the sub does not need the most fidelity, get something that is reputable but not too expensive. you do not need necessarily 750 watts RMS, something less powerful will suffice also

I would probably get something like this, cheap, reliable and efficient
http://cgi.ebay.com/2009-KENWOOD-KAC...1|293:1|294:50
Old 05-29-2009 | 10:44 PM
  #34  
Pearl96Max's Avatar
I tend to get a bit irritable
iTrader: (151)
 
Joined: Feb 2002
Posts: 17,671
From: Central Jersey
Earlier you said that the enclosure is 'ready' for either 2 or 4Ohm correct ? You later found that it is wired for 2Ohm leading to believe that you have dual 4Ohm coils. If the amp is shutting down, then chances are quite good that it cannot handle a 2Ohm mono load. Not sure where Any of this 1Ohm load stuff came from ..

Also quite confused how anything can be 'ready as 2 or 4 ' unless referring to the enclosure itself and having a different model sub in it at ship time. With a dual coil driver it is im possible to achieve 2 or 4. 2 or 8 - yes, 1 or 4 - yes. It is either going to essentially double or be cut in half from the root.
Old 05-29-2009 | 10:47 PM
  #35  
Pearl96Max's Avatar
I tend to get a bit irritable
iTrader: (151)
 
Joined: Feb 2002
Posts: 17,671
From: Central Jersey
Originally Posted by Calcvictim

4)bridging is done when you have 2 amplifiers powering the same speakers, what it effectively does is make both act as a single amp and the power of both is combined(Captain Planet baby)

because you only have one amplifier no bridging should be happening
What ?!?!?!

Originally Posted by Calcvictim



the way to bridge an amp is to connect one channel positive to the second channel negative and use the unocupied terminal for the speaker/sub

Did you just suggest he connect two outputs to each other ?
Old 05-29-2009 | 11:31 PM
  #36  
ryan_green1337's Avatar
Thread Starter
Member
 
Joined: Dec 2008
Posts: 72
From: CA
Originally Posted by Calcvictim
just my opinion but the sub does not need the most fidelity, get something that is reputable but not too expensive. you do not need necessarily 750 watts RMS, something less powerful will suffice also

I would probably get something like this, cheap, reliable and efficient
http://cgi.ebay.com/2009-KENWOOD-KAC...1|293:1|294:50
looks good for the price but it says that the 1 ohm load will provide 900 watts. is that max watts or rms? 900 is too high for just one cvx
Old 05-29-2009 | 11:43 PM
  #37  
Pearl96Max's Avatar
I tend to get a bit irritable
iTrader: (151)
 
Joined: Feb 2002
Posts: 17,671
From: Central Jersey
Originally Posted by ryan_green1337
looks good for the price but it says that the 1 ohm load will provide 900 watts. is that max watts or rms? 900 is too high for just one cvx
So your back to being 1Ohm ? Is final impedance 1 or 2 ??

If 1, then simply wire it in series for 4.
Old 05-29-2009 | 11:59 PM
  #38  
choray911's Avatar
The Crazy Azz Cracka
iTrader: (1)
 
Joined: Aug 2003
Posts: 3,035
From: Chattanooga, TN
Originally Posted by Calcvictim
he will lose power if he wires it that way, if his amp is 2 ohm stable which it is it doesn't make sense to wire it into 4 ohms



I am guessing you want the most power out of the sub, if that is the case then you want to wire each coil seperately to each one of the channels

looking at the specs on the website you can wire the sub and amp 2 ways

way 1)2 coils are wired in series as importcf suggested, resulting in your sub having one 4 ohm load, then you can bridge the 2 channels and in result you have 250 watts of power
way 2)seperately wire each coil to each channel and you have 2 2ohm loads, which give you 2 channels at 200 watts each


I would choose way2
This chart does not apply to OPs situation, completely disregard. Traditional amps are not 2 ohm stable bridged. When you bridge the amp the left and right outputs are combined internally and the impedence is cut in half. The maximum load that can be bridged is 4 ohms, which internally is 2 ohms when the left and right channels are combined. If you were to put a 2 ohm load bridged on the amp, it would really see a 1 ohm internal resistance, which would cause the power supplies pull more current, thus blowing fuses.

With your set up there is no power difference between a 2ohm stereo connection and a 4 ohm bridged connection. The amp will produce the same amount of power either way.
Old 05-30-2009 | 07:57 AM
  #39  
Calcvictim's Avatar
Member
 
Joined: May 2009
Posts: 133
From: pǝq s,ɐɯɯoɯ ɹnoʎ uı
Originally Posted by Pearl96Max
What ?!?!?!




Did you just suggest he connect two outputs to each other ?
I was unaware that the amp was a 2 channel amp, so I said no bridging should be done.


Amps are bridged by connecting the possitive lead of one channel to the negative of another channel and using the remaining leads to connect the speaker.


an instructions manual for a JL Audio amp is here, if you want to verify
http://safemanuals.com/user-guide-in...AUDIO/300-2-_E
Old 05-30-2009 | 10:02 AM
  #40  
Pearl96Max's Avatar
I tend to get a bit irritable
iTrader: (151)
 
Joined: Feb 2002
Posts: 17,671
From: Central Jersey
Originally Posted by Calcvictim
I was unaware that the amp was a 2 channel amp, so I said no bridging should be done.


Amps are bridged by connecting the possitive lead of one channel to the negative of another channel and using the remaining leads to connect the speaker.


an instructions manual for a JL Audio amp is here, if you want to verify
http://safemanuals.com/user-guide-in...AUDIO/300-2-_E


Taken directly from the exact manual you sent:

To bridge a pair of channels, use the
“Left +” and “Right –” speaker connectors
only (the “Left –” and “Right +” remain unused).


Please, for your own safety do not try your theory. Perhaps you misunderstood what you were reading, so please do not try it. You should Not be connecting the amplifier to itself.


Quick Reply: Amp Blowing fuses



All times are GMT -7. The time now is 09:34 PM.