What is better 2 ohm or 4 ohm subs

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What is better 2 ohm or 4 ohm subs

  • hi veryone i waws wondering if anyone could tell me what is better 4 ohm or 2 ohm subwoofers and im looking at 2 alpine type R subs and the Alpine MRD-M1005 amp and is that a good combo for my 1995 chevy camaro and im getting a t-top box from another website anyone got any advice for me on what is better 2 ohm or 4 ohm and is the combo i am choosing a good one

    [edited by: CAMARO KEVIN at 2:41 PM (GMT -5) on Thu, Apr 19 2007]
  • The answer to your question varies depending on your specific application. Because you stated that you're interested in the "alpine type r subs" I can only assume you're interested in using at least two subwoofers with this amplifier. If this is the case, you will want to select the Dual 2 Ohm models. Currently, this impedance is only available in the 12" size, so, hopefully, the custom box you plan to use will accept this size.

    Because these subwoofers are dual voice coil and the amplifier is a "mono Class D" you will need to wire the two voice coils in series, which will present a 4 Ohm impedance for each subwoofer. You can then wire each subwoofer in parallel to the mono channel amplifier to get the 2 Ohm impedance and the 1000 watts of RMS output. This wattage will be evenly split among the two subwoofers providing 500 watts RMS to each. This application will allow you to realize the full potential of the amplifier and subwoofers at the same time.

    I hope that helps.

    If anyone else can explain this better than I have, please do. It can be a little complicated.

    [edited by: Ryan at 4:38 PM (GMT -5) on Wed, Apr 18 2007]


  • Depending on how many subs you want will have an effect on weather you need a 4 or 2 ohm sub, (neither is better than the other , they are just made at different impedance to give people different wirring options)
    the mrd-m1005 is rated at 1000rms at 2 ohm
    and the type r dual 4ohm wirred in paralell = 2ohm is rated at only 500rms, i would only recommend this amp if you were to buy 2 x type r subs to match the power ratting, 1000 rms is perfect for two and probly too much just for 1 type R, they are made well but even the toughest sub might not withstand double its power rating. ok If you want one type R go for the mrd-6005 which is 600rms at 2 ohm, PERFECT FOR 1
    ALPINE IDA-X100 - PXA-H100 IMPRINT ALPINE SPX-17PRO TYPE X 6.5" front ALPINE SPX-17REF TYPE X 6.5" rear ALPINE PDX 4.150 ALPINE MRD M500 ALPINE TYPE R 300RMS x 2 subs 1.2 Farad Cadence Cap Stinger cabling - Dynamat
  • thanks for the advice and hey i think you guys should look in to putting these boxes on your web site they are sick and they are for camaros and firebirds and do have any idea how dbs my system will put out because i want to know if this setup will break my glass in my 1995 camaro and im putting 2 alpine type r's in with the alpine amp  and can you seguest any other sound proffing other than dynomay because its to expensive and heavy here is the web site to the boxes they make alot of boxes but i think your website just needs the camaro ones especially the t-top box its sweet and just what im looking for and i know lots of guy that are looking for the same kind of box because they want to subs but dont want to give up there t-top storage space and when you look at the t-top box can you tell me what kind of box it is i mean type 1,2,0r 3 and if the subs ive picked will sound good in it  and again im interested in the t-top one but they make many others so if you could take a look and get back to me i would really apreaciate that and im interested the 2 12's t-top box

    here is the website for the boxes




  • I have two type R's and get around 145 - 150 db in a conventional sealed box. They are about three years old now and so is the alpine monoblock, they sound great. The size shape and the volume of the box all contribute to the accoustic sound comming from it, without actually hearing it its hard to say exactly what volume and quality you will get.
    I noticed a picture on the site you posted and someone had two type X 12's and two 1000wat alpine monoblocks l, serious stuff. if the boxes are good enough for them i would say the type r's should be fine , but try and hear a car with the box 1st if posible and see what they are like.
    ALPINE IDA-X100 - PXA-H100 IMPRINT ALPINE SPX-17PRO TYPE X 6.5" front ALPINE SPX-17REF TYPE X 6.5" rear ALPINE PDX 4.150 ALPINE MRD M500 ALPINE TYPE R 300RMS x 2 subs 1.2 Farad Cadence Cap Stinger cabling - Dynamat
  • Depends on what kind of sound you are looking for.  Generally speaking, the lower the impedance, the more power you can move through the speaker, which means more volume.  A higher impedance results in better "damping" or control of the speaker movement.  So the higher impedance will yield a tighter, more accurate sound, although when talking about high quality amps and subs, most people won't notice the difference.
  • No, no no, no, no and no.  Because certain amps make power at a certain resistance, not all subs can be compatible.  And also because certain amps have flexibility in creating power, resistances can be off, and then the wattage can soar!  Because of this, it is often difficult to match the speaker to the amp that one is using.  This is why we have dual impedance subs.  IT IS ALWAYS BEST TO MATCH THE IMPEDANCE OF THE SUB TO THE OUTPUT IMPEDANCE OF THE AMPLIFIER!   Always.  This is why.  IF you connected a sub running at 8 ohms, to an amp running at 4 or 2, the resistance would be great and the amp would run hot.  When this happens it over heats and eventually shuts down resulting in returns.  If the amp is running at 4 ohms and the sub is running at 1 or 2 then the sub gets pushed harder to compensate and the voice coils will generate more heat and lock up.  The only variance available in wiring is thirds.  You can use an amp at 4 ohms to 3 subs totally 3.33 ohms.  Thats ok.  It is not a good idea to run something even a half ohm off, although its not as bad as being a complete unit off.  ALWAYS matching your subs to your amp will not only give you your best efficiency but the most dependability. 
  • I cannot agree with Keith more on this topic. He is absolutely correct. One of the major reasons we get calls from people is that they have blown their subs or burned out their amps. It is all from the lack of matching them up correctly. The easiest way to ruin your equipment is to under/over power your speakers or to run your amp too hot. Even the best amps out there still have ratings that you should pay close attention to and stay within the limits listed. As Keith said, even being slightly off from the recommended impedance levels can damage your equipment.

    Great post, Keith. I bet that if people chimed in on this topic, that we would hear from a lot of people who have damaged their equipment in this way. So, take heed guys and your equipment should last you a long time.

  • Thanks for the props Warren.  I appreciate it.  Maybe we should have a seperate permanent thread that addresses this issue.  That way people can read it first before asking questions or go searching through other threads to find their information.
  • hey all, a question. Im setting up a new system. and I was pretty certain on my sub wiring, but now im not. Im getting a mono amp, and 2 subs that are 4 ohm dual voice coil. Im really hoping i can in some way run them with a 2 ohm load... cause it would match perfectly to my subs rms, if not, im gonna be lacking a good bit. help please!
  • Nope, it would be impossible.  You could run them on a 4 ohm load or a 1 ohm load only.  Well I guess technically you could run them on 1, 4, and 16 ohm loads but ya know. 
  • oh, great... well thanks anyway.
  • I recently got a 2 ohm Alpine type R, would it be compatible with this amp.... http://www.crutchfield.com/S-nQU9qNDEcIP/cgi-bin/ProdView.asp?g=120&I=113KAC8103&search=Kenwood+VENDORID113&SearchDisplay=Kenwood

     Sorry... I know it seems like a dumb question to most of you.

     (I dont know if the link works, the part number of the amp is  KAC-8103D)


    [edited by: ST102688 at 5:14 PM (GMT -5) on Mon, May 21 2007]
  • Since you have the Type-R subwoofers, I would not get that amp. A dual 2 ohm voice coil subwoofer presents either a 1 or a 4 ohm load to the amp. Since most amps are not 1 ohm stable, we use the 4 ohm method. This means that you need to find an amp that outputs something around 500 watts at 4 ohms. The Kenwood KAC-7203 amp is a great choice as it will output 500 watts at 4 ohms in bridged mode.

    Any other ideas?




  • Here's what I'm planning on running: 2 Kicker 15" L7s (2000peak/1000rms) in a sealed box with a Rockford Fosgate T20001bd amp (2000w @ 1ohm, 1500 @ 2ohm). It will be going in a Ford Focus ZX3 hatchback. Would it be better to go with the 4 ohm DVC run in parallel/parallel for a 1 ohm output or the 2 ohm DVC run in series/parallel for the 2 ohm output? I know that I would get a little more power gains at 1 ohm but would it really be necessary?