
 Thread Tools  Search this Thread 
3rd July 2006, 00:32  #1 
BHPian  Subwoofer Coil wiring Doubts I am new here, had few doubts on how to wire subs with amps keeping in mind the Impedance, Saw some people's posts and thought this is the best place to clear them out, Now I had 3 main doubts , 1) Suppose I have a pair of Single 4 Ohm Voicecoil subwoofers , and want to run it with an Mono Amp which is 2 Ohm Stable, how do we wire both to get the optimum output from the amp which is at 2 Ohms. Also how should I wire it if it had to be run on a 2 Channel amp whose Bridged max output is at 4 Ohms. 2) Suppose I have a pair of Dual 4 Ohm voicecoil subs, and want to run them with the same two amps above how would it be wire to get max output ? 3) Suppose I am running one Single 4 Ohm Voicecoil amp with a single 2 Ohm Stable amp, if I directly connect the sub + ,  to the subwoofer's + ,  terminals, will the amp set itself to 4 Ohms and produce the output it can produce only at 4 Ohms and not peak power which is at 2 Ohms. 

3rd July 2006, 06:50  #2 
Distinguished  BHPian  lol, in teh first case its 2 againt 4, teh second either 1 or 4 and third is same as 1. Clipping happens? By the way, wont one damage teh sub/amp if connect so? 
3rd July 2006, 10:16  #3 
Senior  BHPian Join Date: Feb 2006 Location: Bangy Boy!
Posts: 1,554
Thanked: 12 Times
 029RON  Aint no guru but here goes.... 1) Suppose I have a pair of Single 4 Ohm Voicecoil subwoofers , and want to run it with an Mono Amp which is 2 Ohm Stable, how do we wire both to get the optimum output from the amp which is at 2 Ohms. You wire the subs in PARALLEL 4 / 4 =2ohm Also how should I wire it if it had to be run on a 2 Channel amp whose Bridged max output is at 4 Ohms. you Wire it in SERIES 4+4 = 8 ohms. In this case however you will be presenting an 8 ohm load  generally avoided when doing subs because this reduces the amps output. Ideally you should go for TWO 2 ohm subs IN SERIES to make use of this option, Or if you want to use your 4 ohm subs you will have to get yourself a amp that is stabel @1 ohm 2) Suppose I have a pair of Dual 4 Ohm voicecoil subs, and want to run them with the same two amps above how would it be wire to get max output ? Well you can do ('/' indicating parallel and '+' indiicating series) a) 4+4+4+4 = 16 ohm b) (4+4)/(4+4) = 4 Ohm (or the other way  same result  (4/4)+(4/4) c) (4/4)/(4/4) =.0.5 ohm or is it 1 ohm  slight blip here.. d) Wire them in Stereo  one sub per channel (parallel or series depending on the amp and the above philosopy) 3) Suppose I am running one Single 4 Ohm Voicecoil amp with a single 2 Ohm Stable amp, if I directly connect the sub + ,  to the subwoofer's + ,  terminals, will the amp set itself to 4 Ohms and produce the output it can produce only at 4 Ohms and not peak power which is at 2 Ohms As explained taking higher impedences than an amps rated minimum impedance is normally not a problem... in certain instances its acually good  the amp has to work a lot lesser. This comes with a max power tradeoff. However I dont think this is optimal for Sub loads  The GURU's will now elaborate!!... Last edited by kb100 : 3rd July 2006 at 10:20. 
3rd July 2006, 11:15  #4 
TeamBHP Support Join Date: Mar 2004 Location: mumbai
Posts: 21,467
Thanked: 3,192 Times
 I thiknk KB covered it. 1. Parallel both coils to get 2 ohms. 2. parallel both coils of each sub and run the amp in stereo (2 ohms per channel) most amps that are 2 ohm stable in mono can manage 2 ohms in stereo rather well. 3. amp will manage well and maybe even run a bit cooler. 
3rd July 2006, 13:04  #5  
BHPian  Quote:
3. Amp will manage well indeed but will it set itself to 4 Ohms ? so for example: if the mono amp's output is 400 RMS @ 4 Ohms and 800 RMS @ 2 Ohms then will it produce 400 RMS If I wire a single 4 Ohm sub directly to the +, of the amp ?  
3rd July 2006, 13:20  #6  
Distinguished  BHPian  Quote:
 
3rd July 2006, 14:11  #7  
BHPian  Quote:
 
3rd July 2006, 14:45  #8 
TeamBHP Support Join Date: Mar 2004 Location: mumbai
Posts: 21,467
Thanked: 3,192 Times
 929, what is the amp in question. some amps handle 2 ohms better than others. 
3rd July 2006, 15:33  #9  
Distinguished  BHPian  Quote:
1) Suppose I have a pair of Single 4 Ohm Voicecoil subwoofers , and want to run it with an Mono Amp which is 2 Ohm Stable, how do we wire both to get the optimum output from the amp which is at 2 Ohms. You wire the 2 subs in PARALLEL 4*4/4+4 =2ohm and then connect it to teh amp which has 2 ohm impedence. 2) Suppose I have a pair of Dual 4 Ohm voicecoil subs, and want to run them with the same two amps above how would it be wire to get max output ? same as setup 1) and connect each pair to each sub ! 3) Suppose I am running one Single 4 Ohm Voicecoil amp with a single 2 Ohm Stable amp, if I directly connect the sub + ,  to the subwoofer's + ,  terminals, will the amp set itself to 4 Ohms and produce the output it can produce only at 4 Ohms and not peak power which is at 2 Ohms As explained taking higher impedences than an amps rated minimum impedance is normally not a problem... in certain instances its acually good  the amp has to work a lot lesser. This comes with a max power tradeoff. However I dont think this is optimal for Sub loads   
3rd July 2006, 22:26  #10 
BHPian  Thanks for the heads up everybody, made some doubts clear for me, I was a little confused 
4th July 2006, 11:13  #11  
BHPian Join Date: Mar 2005 Location: Singapore
Posts: 262
Thanked: 0 Times
 Quote:
Amps dont 'set' themselves in case you are thinking that there's a switch or setting of some sort.. Its the simple V=IR relationship.. The amp supplies a current based on the impedance it 'sees', in an inverse relation.. So, keep reducing the impedance and the amp's current increases, till it cant handle it, starts clipping, and then finally blows.. Last edited by nitinbhag : 4th July 2006 at 11:14.  
Thread Tools  Search this Thread 
Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Zen MPFI wiring manual/wiring diagram  IndrojitSircar  Technical Stuff  1  27th February 2012 00:21 
Active Subwoofer vs Free Air/Enclosed Subwoofer  Epic  InCar Entertainment  2  2nd December 2009 10:59 
Subwoofer Wiring  gunbir  InCar Entertainment  57  26th March 2007 10:25 
Doubts  qqplus  Technical Stuff  15  10th February 2006 23:20 
Doubts abt airbags  speedsatya  The Indian Car Scene  4  5th September 2004 13:20 