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Alright, i got TWO (2) 12" Rockford Fosgate DVC subs that can EACH handle 400w RMS. I would like to go with a class D JBL Amplifier. I've been told that since each sub has 2 voice coils (DVC = Dual Voice Coil) the wiring configurations I can have are 4 ohms mono, or 1 ohm.
- Is this true?
- What does this 4 ohms mono, or 1 ohm mean?<p>
I was looking at the JBL BP1200.1 over at http://www.jbl.com/car/product.asp?prod=BP1200.1&ser=POS&cat=AMP.
- How much RMS will this amp put out to BOTH of my subs?
- Is this an ideal amp for my application?
- Would the JBL BP600.1 over at http://www.jbl.com/car/product.asp?prod=BP600.1&ser=POS&cat=AMP be better?
- Is it ok to have an amp putting out 600w RMS to a 400w RMS rated sub? Will it damage it?<p>
As you can see i don't have a clue what im talkin' about <p>[ April 21, 2003: Message edited by: zytariuk ]</p>

ok lets get things rolling here. since your subs are dual voice coil there is one question. are they a dual 4 ohm coil or a dual 2 ohm coil? well i'll give you the answer for both.<p>Dual 4 ohm coil
you have a choice of a 1 ohm load or a 4 ohm load depending on your choice of amp.<p>Dual 2 ohm coil
you have a choice of a .5 ohm load, a 2 ohm load or a 8 ohm load.<p>Ohm is the name for the resistance of the electricity flowing threw the metal, less ohms less resistance wich means better performance. in the perfect world the ohms would be zero, meaning no resistance!! I only wish this could happen!!<p>Amplifier for your subs I'm takin a wild guess here and think that you got the RFP3212 subwoofer? In that case neither of those two amps would work. you need to find a mono amplifier that is .5 ohm stable, and has a max output of 800 watts to about 1200 watts to take your subs to their full potentional. <p>BUT in your case, i'm not sure about your money situation, and how much of looking around you want to do, you could get a mono amp that does 800 watts to 1200 watts at 4 ohm, this will sound nice, but nothing compared to what they could sound like with a .5 ohm load! BUMB BUMB BUMB. and of course in a sealed box, the .5 ohm load would give you the loudest and clearest sound out of the two choices.<p>I hope this helps you out in the quest for the "perfect" system. but remember, it's all about what you want, and not what others think. anymore questions, just drop a line.

Actually i have the RFP-1212, and acording to the specs sheet on my subs over at http://www.rockfordfosgate.com/rftech/library/1997/5_Subwoofers/RFP-1212-TS.pdf . . .the 'Nominal Impedance' is 2 x 4 Ohm's.<p>
- Would the JBL BP1200.1 over at http://www.jbl.com/car/product.asp?prod=BP1200.1&ser=POS&cat=AMP be ideal for my setup?
- How much RMS will this amp put out to BOTH of my subs?
- Is it ok to have an amp putting out 600w RMS to a 400w RMS rated sub? Will it damage it?
OR
- Would the JBL BP600.1 over at http://www.jbl.com/car/product.asp?prod=BP600.1&ser=POS&cat=AMP be better? Also, how much RMS will this put out to BOTH my subs?<p>
Thaks for you're help. Sorry about all these dumb questions :\<p>[ April 21, 2003: Message edited by: zytariuk ]</p>

hello again, no question is dumb, better to ask than to guess. first lets go about the amp. the JBL 1200.1 is the closest, altho it wont run the subs at full potention, because you have dual 4 ohm load all you can do is a 1 or 4 ohm load, not a 2 ohm. so there for the 1200.1 will only alow you to get 600 watts total, and thats 300 watts per sub, 150 watts per coil. not at full potental. you CANNOT run this amp at the 1 ohm load for the subs. the amp will blow. not good. the 600 watt amp only does 300 watts total at a 4 ohm load. no good this amp will never work. the 1200.1 amp could work, but it is not recomended. beacuse the total watts put out is less than the RMS of the sub wich will in return fry the sub, yes it is possible with not enough watts or too much watts. i recomend finding a different amp. look towards Kenwood mono amps i know they have some 1 ohm stable amps wich would work excelent for you. anymore questions, ill be checking back later. good luck

What about if i use both the JBL BP1200.1 & JBL BP600.1. That should get me 375w RMS per sub, which soudn't fry the sub...right?

<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by z_x71:
hello again, no question is dumb, better to ask than to guess. first lets go about the amp. the JBL 1200.1 is the closest, altho it wont run the subs at full potention, because you have dual 4 ohm load all you can do is a 1 or 4 ohm load, not a 2 ohm. so there for the 1200.1 will only alow you to get 600 watts total, and thats 300 watts per sub, 150 watts per coil. not at full potental. you CANNOT run this amp at the 1 ohm load for the subs. the amp will blow. not good. the 600 watt amp only does 300 watts total at a 4 ohm load. no good this amp will never work. the 1200.1 amp could work, but it is not recomended. beacuse the total watts put out is less than the RMS of the sub wich will in return fry the sub, yes it is possible with not enough watts or too much watts. i recomend finding a different amp. look towards Kenwood mono amps i know they have some 1 ohm stable amps wich would work excelent for you. anymore questions, ill be checking back later. good luck<hr></blockquote><p>Obviosuly you've never used a 1200.1 before. The jbl 1200.1 is fine down to 1 ohm load, anything below 1 ohm is a little risky, but it has built in protection on the amp in case of thermal. <p>Also the JBL 1200.1 does 1200 watt @ 2 ohm or 1 ohm, and 600 watts at 4 ohm.

So i would need TWO (2) JBL jbl 1200.1 amps putting out 600w RMS to each sub correct? Cause i need at least 400RMS PER SUB...

no, listen to loudsubz. YOu can run the JBL at 1 or 2 ohm (the amp puts out identical power at both ohm loads). The amp will give your subs 600 watts a piece and you will be plenty loud.

yup that amps a beast at 1 ohm and will work fine

Sorry guys,
I want THE SAME sub, but I'll put only one of them (RFP 3212), can you please tell me why you suggest a mono amp? I thought 2way amp was needed to run a DVC sub, am I wrong?

no, you are incorrect. You can run a DVC sub w/ a 1 channel amp.<p>Where does this 2 "way" name come from? I've never heard anyone call it a way instead of a channel.

if you can run 2 (or more) subs on a monoblock amp, you can definatly run a DVC sub on a monoblock amp. Here is a pretty easy (yet VERY simplified) way of thinkinf about a DVC subwoofer. When you power a SVC sub you are running one voice coil, DVC (Dual Voice Ciol) subs have 2. So you can basically think of it as running 2 subs. Easier to understand that way.

<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by BumpNGlow:
no, you are incorrect. You can run a DVC sub w/ a 1 channel amp.<p>Where does this 2 "way" name come from? I've never heard anyone call it a way instead of a channel.<hr></blockquote><p>
Sorry man! I translated it wrong.. in Italy we say 2way or 2channel for the same thing!

some peopel also get 2 way mixed with channels because u say a 2 way crossover which is correct it crosses over at 2 frequencies.

Just to let you guys in on a little secret. The JBL 1200.1 & 600.1 are under rated. I currently have the JBL 600.1 running at 2ohm load on my 2 12" Infinity Kappa's. I measured the output at 3/4 volume at close to 420watts each sub. Now thats alot of power for 300watt subs.. hehe