So I need help picking out what kind of amp I need to run my sub, and door speakers. My sub pushes 500w but then settles down to 250 RMS and it's a "2 ohm Duel voice coil" which means I can wire it in series, in parallel or indipendent. I have no idea what that even means or what the pro's and con's of each set up. I also have four 70 watt 35 RMS door speakers I wanna run off the amp but I have no freaking clue what kind of I need to be looking at and if the rated value on the amp is how much it pushes constantly or if it settles down like the speakers.

I don't understand on my "duel voice coil" sub why you would wire it in parrell to make a 2 ohm sub into a 1 ohm load for the amp, or why you would wire it in series to make the 2 ohm sub a 4 ohm load for the amp? What's the difference? When change the ohm load does that mean the amp has to push more watts?

Please help guys. I got a system to build.

 

So you have a 250 Watt(RMS) dual voice coil sub. They make dual voice coil subs to make it easy to wire up different configurations. The 2ohms is the resistance each coil has. The sub doesnt push, it pulls current and has resistance(Ohms). The less ohms, the less resistance and more power(relatively).

With a dual 2ohm voice coil you have the choice of running at 4ohms or at 1ohm. Typically you want to run a sub at a lower load(ohms) to get the most power, but in your case; its not hard to find an amp that pushes 250 @ 4 ohms.

Your amp really doesnt change watts, your subs create resistance (measured in ohms) to allow your amp to push more power.

I would go with an Alpine MRP 500 to power the sub. Great amps and would power the sub perfect at 4ohms. It's generally hard to find a cheap amp that will hold a 1ohm load. If you wire a sub to a load below what the amp is capable of, it will destroy itself.

For instance, say you wire yours in parallel for a 1ohm load. You have to find an amp that will power a sub at 1 ohm or below (1/2 ohm). If you wire your subs at 4ohms any amp will be able to power them and not hurt the amp itself. Most of the higher-end amps (around 1000 rms or more are always 1ohm stable allowing you to put out tons of power. 4ohms is more efficent on your electrical system and is what I think you should wire it to the amp as.

Check out the Alpine MRP 500. Its a mono amp which is stable from 2 ohms up. Also note: whenever an amps says 2 ohm stable, it means it will handle any load greater than 2ohms including 2.

 

Always look at RMS, Max wattage is merely a made up number. For your door speakers you will need a 4-channel amp that will put out around 40-50 watts rms per channel.
Most 4-channel amps are made for 4-ohms, however some even handle 2ohms. However, you don't need a 2ohm stable amp because your door speakers arent going to be ran in parallel.

Check out some Rockford Prime Series and Alpine MRP 300. Good amps for the price, and getting an amp which is capable of producing a little more power than the speakers are rated for isnt an issue. You can decrease the power with tuning the gain and settings on the amp.

 

Thanks guys
So do I need 2 amps one to run my door speakers and the other to run my sub?

 

You have two routes.
Find a 5-channel amp (Sub Channel needs to be around 250rms at 4ohms) the other 4-channels(for the doors) are really irrelevant. Most 5-channel amps have greater than 35 watts rms per channel

or

A mono amp (250 at 4) for the sub, and a 4-channel amp.

I can post some links up if you would like.

 

One amp would be less work and ease of install would probly be a good plus

 

THese are 5-channels. No other amps would be needed, and these fit your application perfect.
http://www.crutchfield.com/p_113KAC7...AC-7005PS.html
http://www.crutchfield.com/p_105AX32...S-AX3205D.html


Going the other route you will need one of these (4-channel amp)
http://www.crutchfield.com/p_777M405...ce-M-4050.html
http://www.crutchfield.com/p_500MRPF...-MRP-F300.html
http://www.crutchfield.com/p_575R300...me-R300-4.html

and you will need a mono amp (with 250 rms at 4ohms)
http://www.crutchfield.com/p_777M150...ce-M-1500.html
http://www.crutchfield.com/p_575R500...me-R500-1.html
http://www.crutchfield.com/p_500MRPM...-MRP-M500.html

 

5-channels save alot of hassel when installing. But they don;t leave room to upgrade the system later if you change speakers or subs.

 

That is a very good point but if he decided to go up later, adding another sub, couldn't he just stop using the 5th channel and wire in the correct amp in for the load? It would still be the same amount of wiring to make it right. You said yourself earlier that any decent 5ch will have more than enough juice to run the door speakers.

 

Yeap, he sure could. But 250 bucks for a 5-channel amp is kinda steep when you are only using the 4-channel aspect. 250 for the 5-channel + 150 for another sub amp or more is getting upwards of 500 bucks.

Unless you are planning on upgrading door speakers or adding subs, I wouldnt worry about the expanding aspect. For what you have now, the 5-channel is perfect.

If you want 75 watt door speakers later on, then the 5-channel isn't the way to go.

My sister works for Crutchfield (ZOE aka Christy), so I get discounts on all their audio stuff. I have the Focal K2's in the front, Type R's in the rear, two 1000rms type R subs, Focal FFP 4100 amp & Rockford T1500 amp.
At retail cost, thats probably over 3500 bucks.