Free Shipping on Everything.
60-Day Money-Back Guarantee | Lifetime Tech Support

Help with ohms and amp wiring

Car Audio, Video, & GPS

Car Audio, Video, & GPS
Talk about stereos, navigation, amps, subs, and all things car audio

Help with ohms and amp wiring

  • Just have'nt quite got these ohms figured out yet. I have a kicker CVR12 4ohm DVC sub in a kicker enclosure, when I connect this to an amp is it "always" introducing a 4ohm load? I ask because the amp I have it hooked up to does 300wattsrms x2 @4ohms but when bridged it does 600x1 @ 2ohms. So when I bridge it would it be able to utilize the 600watts or will it only see 300w because it is a 4ohm sub?

     

     

  • the amp is at 2 ohms bridged, that wont change, but you need to make sure you have the sub wired properly, if not you can blow a voice coil very easily(ive done it with a 500 dollar set of audiobahns subs.) to make the sub work with your amp at 2 ohms, you need to wire the sub at 2 ohms. so the ohms match.  number one coil is the two terminals with white dots on them, the other two with solid colors are voice coil number 2. to wire the sub in 2ohms, you need to wire in parallel, so connect bot the positive(red) terminals(of number one and two) with a peace of speaker wire, and both the negative(black) terminals with a peace of speaker wire. the connect you wires coming from you amp to the number one terminals(the ones with white dots). i know this may sound confusing, so you can look in your owners manual and it will show you, or you can get on kicker.com and find the manual for your sub to see picture of what im talking about.
  • What is your amp?  B/c most amps that are 300Wx2@4-ohms would not be stable at 2-ohms bridged, or would put out more than 600Wx1@2-ohms bridged,

    But, if those specs are correct, you wire it like this:

     

    2002 Ford Focus JVC KD-A815 Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs

  • Sorry, that was a typo it was suppose to say 600W x 2-Ch @ 2-ohms. The amp is the CrunchPzi325.3 I mentioned in another thread.

    I tried bridging it without changing the wires on the sub and it had about the same amount of power as using one channel. Could that damage the sub it seems to be fine?

  • h2OBfFlo:
    the amp is at 2 ohms bridged, that wont change, but you need to make sure you have the sub wired properly, if not you can blow a voice coil very easily(ive done it with a 500 dollar set of audiobahns subs.) to make the sub work with your amp at 2 ohms, you need to wire the sub at 2 ohms. so the ohms match.  number one coil is the two terminals with white dots on them, the other two with solid colors are voice coil number 2. to wire the sub in 2ohms, you need to wire in parallel, so connect bot the positive(red) terminals(of number one and two) with a peace of speaker wire, and both the negative(black) terminals with a peace of speaker wire. the connect you wires coming from you amp to the number one terminals(the ones with white dots). i know this may sound confusing, so you can look in your owners manual and it will show you, or you can get on kicker.com and find the manual for your sub to see picture of what im talking about.

    So if I understand you correctly there is no physical/mechanical difference in a 4ohm vs a 2ohm sub it is strictly how the sub is wired?

  • I would run it off one channel, simply b/c we are pretty sure the amp is 600Wx2@2-ohms so off the one channel you are getting 600W in a stable configuration.  The amp is rated at 600Wx1@4-ohms bridged (or I saw 1200W floating around), but we don't know what it outputs at 2-ohms, other than it is not supposed to be stable.

    I'm not that worried about it damaging the sub as much as putting the amp into protect mode. 

    2002 Ford Focus JVC KD-A815 Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs

  • Bammer:
    So if I understand you correctly there is no physical/mechanical difference in a 4ohm vs a 2ohm sub it is strictly how the sub is wired?

    Somewhat, I don't think you are understanding it quite yet.

    Your sub can be wired at 2-ohms or 8-ohms, there is no way (unless you had a pair of them) to wire it at 4-ohms.

    Your sub will sound the same with a 600W amp at 2-ohms as it will with a 600W amp at 8-ohms, but it will take a much more powerful amp to produce 600W at an 8-ohm load.

    The DVC-2-ohm model of your sub from the same company can be wired at either 1-ohm or 4-ohms, and should sound about the same as above with either a 600Wx1@1-ohm amp (hard to find) or a 600Wx1@4-ohm amp.

    There are of course mechanical differences in the voice coils between the DVC-2-ohm and DVC-4-ohm sub.

    HTH!!! 

    2002 Ford Focus JVC KD-A815 Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs

  • TigerHeli:

    Bammer:
    So if I understand you correctly there is no physical/mechanical difference in a 4ohm vs a 2ohm sub it is strictly how the sub is wired?

    Somewhat, I don't think you are understanding it quite yet.

    Your sub can be wired at 2-ohms or 8-ohms, there is no way (unless you had a pair of them) to wire it at 4-ohms.

    Your sub will sound the same with a 600W amp at 2-ohms as it will with a 600W amp at 8-ohms, but it will take a much more powerful amp to produce 600W at an 8-ohm load.

    The DVC-2-ohm model of your sub from the same company can be wired at either 1-ohm or 4-ohms, and should sound about the same as above with either a 600Wx1@1-ohm amp (hard to find) or a 600Wx1@4-ohm amp.

    There are of course mechanical differences in the voice coils between the DVC-2-ohm and DVC-4-ohm sub.

    HTH!!! 

    Ok now I'm really confused, My Kicker sub is a 4ohm sub. "Your sub can be wired at 2-ohms or 8-ohms, there is no way (unless you had a pair of them) to wire it at 4-ohms." Not trying to be difficult, just want to make sure I understand this.

     

     

     

  • Your sub is a DVC-4-ohm sub (Dual Voice Coil) meaning each voice coil (it has two of them) is 4-ohms and with them both wired up, the sub is either 2 ohms (parallel VC's) or 8-ohms (series VC's).  It cannot be 4-ohms total (unless you wired two DVC subs with the VC's in series at 8-ohms and then the subs themselves in parallel to 4-ohms).

    Common sub types:

    DVC-4-ohm (what you have) - Can be either 2-ohm or 8-ohm at the amp.

    DVC-2-ohm (other Kickers) - Can be either 1-ohm or 4-ohms at the amp.

    SVC-4-ohm - Has only one voice coil - is 4-ohms or with two can be 2-ohms at the amp (but each individual sub is always 4-ohms)

    SVC-2-ohm - one voice coil - 2-ohms or a pair could be 1 or 4 ohms.

    Much less common:

    SVC-8-ohm

    SVC-6-ohm

    DVC-3-ohm

    etc. 

    2002 Ford Focus JVC KD-A815 Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs

  • Thanks, that really helps clear it up for me. Now one more question if you don't mind, what could happen if you get it wrong and connect say the DVC-4-ohm sub to a 4ohm amp load or a dual set of SVC-8-ohm subs to a 2ohm load? I only ask because I've done this not knowing better and I'm sure others have done the same. I'm not running them like that now but the weird thing was in both cases it seemed to work just fine? 
  • Looks like I have another question, my DVC-4-ohm kicker is wired to a 2channel amp bridged for a 2ohm load. According to the Crutchfield Advisor wiring diagram, this is fine with a mono channel amp but with a 2 channel amp it shows an 8ohm load at the amp?
  • Okay, you still aren't getting this.

    You cannot wire a DVC-4-ohm sub (single) to a 4-ohm amp load - the sub is the amp load and you can't get 4-ohms out of it.  You can wire it at 2-ohms to an amp that is only stable at 4-ohms and the amp will put out more power than designed until it goes into protect mode and overheats, or otherwise overheats (bad), or you can connects it as 8-ohms to an amp that is really designed to make power at 4-ohms, and this can cause the amp or sub to overheat as well, but usually will be okay, but the amp will produce less power than you want, likely.

    Same thing with your second question - dual SVC-8-ohm subs will either be 4-ohms (parallel) - likely okay, or 16-ohms (series), likely not enough power from the amp, you can't wire them to a 2-ohm load - not physically possible (unless you added some high-current resistors to the circuit, but...).

    That's the practical explanation, the more technical one is in this thread

    2002 Ford Focus JVC KD-A815 Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs

  • Looks like I have another question, my DVC-4-ohm kicker is wired to a 2channel amp bridged for a 2ohm load. According to the Crutchfield Advisor wiring diagram, this is fine with a mono channel amp but with a 2 channel amp it shows an 8ohm load at the amp?

    Nope - again not possible.

    If you have it wired in parallel (like CF shows for a mono-amp), you have a 2-ohm load on the amp and most two-channel amps cannot support this in bridged mode (although some can).

    If you have it wired in series (like CF shows for a 2-channel amp) you have an 8-ohm load on the amp and it is putting out approx half as much power as it would at 4-ohms.

    If you look carefully at the CF diagrams they are not the same, in the mono amp one, the wire goes from the positive amp terminal to the positive terminal of both coils.  In the two-channel amp diagram, the wire goes from the postive amp terminal to the positive terminal of the first voice coil, and then a second wire goes from the negative terminal of the first VC to the positive of the second.

    HTH! 



    [edited by: TigerHeli at 4:07 PM (GMT -5) on Sun, Oct 07 2007]

    2002 Ford Focus JVC KD-A815 Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs