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Ok, just need some info on how big of an amp to order. I've ordered 2 memphis 10" subs, * Peak: 500 watts * RMS: 250 watts 4ohm. Most of the amps I've seen are 2 channel, 1000 watt but they are only doing 2 channels at 4 ohms for 175 per channel, which is no where close. Can you guys suggest a decent amp?

-William

I'm no expert on this, but in doing my recent research/shopping/Q/A it really depends on how you wire the system. Assuming you ordered dual voice coil subs and to quote Crutchfield.com, "A dual 4-ohm voice coil subwoofer with its coils wired in parallel presents a 2-ohm load to your amplifier. Since an amplifier produces more wattage at a lower impedance, the parallel connection ensures you'll get the most output from your amp. In the same fashion, if you have a stereo amplifier and two DVC subs, wire both subs for 2-ohm impedance (one per channel) for maximum output." Look for the 2-ohm rating on the amp to determine what you can really get out of it.

I'm not sure what a good two-channel amp is, but my Kicker mono block is pretty nice.

Ahh so I'm just reading it wrong then.

So if the amp says this

# RMS Power (4 ohms) 150 watts x 2 channels
# RMS Power (2 ohms) 225 watts x 2 channels

then it would push the 2 10" that say * Peak: 500 watts * RMS: 250 watts 4ohm

-William

Always look at the RMS of an amp and at what OHMS that is power is being produced. A amp that does 800 watts at 1 ohms is not going to help you if you are running a DVC 4 ohm sub.

What sub do you have? What ohms is it? How much do you want to spend on a amp?

Since I blew close to $200 on the box (shipped) I've had to go cheaper than I wanted to on subs and amp.

Went for 2 of these
15-PR10D4 - Memphis 10" DVC Subwoofer

As for amp I'll spend what I need to, the cheaper the better, without sacrificing quality. Dont want an amp that's going to overheat or something stupid. Would like to keep the amp under $200, but if it's not possible, it's not possible.

-William

I think you could go safely with a kicker or a hifonics amp and still meet a good budget. I will have to look into what models a little later.

Thanks for the links, I'll buy one. The Hifonics seems to have the highest output, but it's also the cheapest which makes me thing the other might be better choices. Since those are all 1 channel or mono amps will I need to run in bridged mode to support 2 subs? As usual forgive the beginner questions, just trying to help myself understand what does what.

-William

I did not know you were running 2 subs. In that case you are going to need a bigger amp and more output from them.

Quote:

Originally Posted by bigaudiofanat (Post 224367)

I did not know you were running 2 subs. In that case you are going to need a bigger amp and more output from them.

Yeah that was the problem I was running into, picking a higher watt amp that the RMS matches those on the speakers. It seems like I would need 1200 watt amp to push 2 10s, because apparently they mark it was 1200 watts but thats for 1 ohm, 1 channel.. Split that to 4 ohms 2 channels it's like 200 watts per channel, still not even getting the 250 per speaker.

Maybe I'm understanding it wrong, any help would be appreciated.

-William

You could get a 4-channel amp and bridge it to 2-channels @ 4 ohms for 325W x 2 channels. For instance, Kicker has this one:

ZX650.4 - Kicker 4 Ch 650 Watt ZX Series Amplifier

I have seen this on on Ebay for around $265...just a suggestion.

Not sure if this works with the DVC but again...I'm not a pro.

You are not going to need 1200 watts to run 2 of those subs. There RMS is like 300 so the max RMS you should look for is like 750.

So look for something that puts out around 600-800 watts RMS at 1 ohms

http://www.the12volt.com/caraudio/wo...s.asp~Q~2~I~42

Quote:

Originally Posted by OVERZLUS (Post 224428)

I do not recommend a 4 channel amp for running subs. They are not made to run subs does not mean they can not but class D amps run subs better and run cooler as well.

GM-5400T - Pioneer 2 Channel 760W Amplifier

760 watts, but it shows 4 ohms: 125 watts x 2 chan. So each channel only gets 125watts? Or am I reading this all wrong. Thanks for all your help guys.

-William

Oh at 1 ohms, ok I will look for that, when you have time could you explain why I'm looking at 1 ohms instead of 4?

-William

Quote:

Originally Posted by bigaudiofanat (Post 224437)

I do not recommend a 4 channel amp for running subs. They are not made to run subs does not mean they can not but class D amps run subs better and run cooler as well.

True...that's why you are the pro...to help us dazed and confused people! can you recommend a decent 2-channel class D amp?

Quote:

Originally Posted by bigaudiofanat (Post 224437)

I do not recommend a 4 channel amp for running subs. They are not made to run subs does not mean they can not but class D amps run subs better and run cooler as well.

Although, two of the original recommendations that you gave were Class A/B amps (Rockford and Hifonics)...

XMZR1252 - Sony 2 Ch. 800 Watt ZR Series Xplod Amplifier

That may be more than I need, but the price is great, curious if you had any thoughts on it. It does seem very big and hard to find a good spot to mount it.

-William

Yes it is 125 watts per channel but will probably put out more after you set your gains.

From Car Audio 101

Quote:

Ohm's

Okay ohms or Ohm's law is the rule of resistance that something has. Most of you probably think about things like rubber and all having high resistance and that is correct. But in car audio we use ohms for what a speaker's resistance is at. For example if you have a sub that has a 4 ohm single voice coil. Than that sub can be wired up to an amp with the resistance of 4 ohms.

The next part of Ohms is power. If you look at any amp's specs you will see that is has something like 100 watts RMS x 4 at 4 ohms (150 watts RMS x 4 at 2 ohms) 300 watts RMS x 2 bridged output at 4 ohms (4-ohm stable in bridged mode) so lets look at the first one. This one states that is can run 100 watts per channel "or speaker" as long as each speakers has a resistance or Ohm's of 4. The second one states that as long as all the speakers are at 2 ohms the amp can put out 150 per channel. The last one shows that it will put out to 2 channels 300 watts a channel if there ohms are 4 ohms. "you will also notice that is says 4 ohm stable at ridged mode." This states that the amp was built for the load of 4 ohms and is able to be bridged.

The thing with ohm's is that the higher the ohms the more resistance. So when you go with a lower ohms rating it can have much more power to run that speaker. You may be asking well can I wire different ohm rated speakers to two different sets output on an amp? You can ONLY do this if the amp is setup for it. If you want to get relay technical about Ohms law just google it and click on any of the first few links that come up. Or just simply ask.

RMS

Now you may have notice in the previous section when watts were being explained it said RMS. Something like 100 X4 at 4 ohms RMS. This is very important when choosing an amp. RMS stands for root men square. In normal terms this means what an amp can continue to produce for long periods of time none stop. You may bee seeing things like 1200 watts MAX. In a few simple words this is a gimmick the amps will never produce this power and no matter how hard you try there just not going to make it. You always look at RMS when shopping for an amp. You will even see it on head units saying 50 X 4 max it is rely putting out around 12-15 watts RMS.

But I still don't understand why if I purchased 2 speakers that are 4 ohm when I look for my amp am I looking at what it outputs at 1 ohm. Just so I'm clear before I order something thought if I find a dual channel amp that is putting out 250 watts per channel at 1 ohm then I have the power I need to run them?

Thanks again man
-William

When you wire the 4 ohm DVC subs to a 2-channel amp, the total impedance will be 4 ohms with the amp bridged. So whatever the amp is rated at 4 ohms will be what you get out of it. I would look for this : *** watts RMS x 1 at 4 ohms (4-ohm stable in bridged mode).

http://akamaipix.crutchfield.com/ca/...hmDVC_4ohm.gif

Thanks overzlus yes when you wire your subs in parallel that is what the FINAL load will be 1 ohms.

Quote:

Originally Posted by bigaudiofanat (Post 225829)

Thanks overzlus yes when you wire your subs in parallel that is what the FINAL load will be 1 ohms.

You lost me there when you mention 1 ohm...how do you come up with 1 ohm? Just trying to understand...

Quote:

Originally Posted by OVERZLUS (Post 224470)

Although, two of the original recommendations that you gave were Class A/B amps (Rockford and Hifonics)...

LOL as I said they can work. Just do not do it as good as more expensive amps that are class d. That is why they are cheaper.

Quote:

Originally Posted by OVERZLUS (Post 226512)

You lost me there when you mention 1 ohm...how do you come up with 1 ohm? Just trying to understand...

When you run 2 4 ohm dual voice coil amps in parallel and they are wired up together the final load is 1 ohm. If it was only 1 of them it could either be 8 ohms or 2 ohms depending on how you wire it. As I said in the 101 thread this is were ti gets confusing to a lot of people.

Here are a few new selections for what you are going to be running

P1000-1bd - Rockford Fosgate Punch 1 Ch 1000 Watt Amplifier

08ZX1000.1 - Kicker 1 Ch 1000 Watt ZX Series Amplifier

MRP-M1000 - Alpine 1000 Watt Mono Subwoofer Amplifier

This one just make sure to really set your gains lol

BXI 2010D - Hifonics 2000W 1 Channel Mono-Block Amplifier

The other wiring diagram is correct but so is this one. You can choose how you want to run it.

http://www.the12volt.com/12voltimage...m_dvc_1ohm.gif

Ok cool, now I understand. Thanks.:tiphat: