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Hi guys,

I've purchased a ALPINE MRD-M1005 specs are;

MRD-M1005 mono subwoofer amplifier

# 500 watt RMS x 1 at 4 ohms (12v)

# 700 watts RMS x 1 at 4 ohms (14.4v)

# 1000 watts RMS x 1 at 2 ohms (14.4v)

And with budget im on wanted a Alpine type x sub, but financially opted for the model below Alpine type r;

Specs being;

Power Handling Capacity (RMS): 500W Dual Voice Coil

Only problem is i was asking the guy @ the audio shop if this sub was a 2ohm or 4 ohm sub. He insisted it was both 2 and 4. Now to my understanding i though subs could only be either 2 or 4 ohm, please correct me if im wrong.

I suggested on wiring up the sub and amp @ 4 ohm @ 12v. which where by i will receive 500rms to the sub and pretty hard on busting it. He suggested the best way being wiring the sub up to the full 1000wrms @ 2 ohm (14.4v) & on the amp turn the gain down therefore you wont stress the amp as much, and will sound better.

Now my questions which im still abit fuzzy on;

* Can this sub be 2 and 4 ohm?

* Is it even possible to output 14.4v from a standard battery which is in a r34.

* And lastly what would be the best way of setting this sub up to my amp. Would you recommended a 2 ohm or 4 ohm setup, and what rms power output?

* Also would i need a capacity for this setup, for time being speakers will be running off the deck.

Thanks guys,

Your help is much appreciated. Cheers :D

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I'm assuming what he meant by 2ohm or 4ohm is that the sub is available with either a dual 2ohm voice coil (SWR-1222D) or dual 4ohm voice coils (SWR-1242D)

The different subs can be wired as such:

Dual 2ohm

Series - 4ohm

Parallel - 1ohm

Dual 4ohm

series - 8ohm

Parallel - 2ohm :/

I would go the dual 4ohm and wire it in parallel as I don't believe the MRD-M1005 is 1ohm stable.

Note: I'm not 100% sure i've got my models correct but it's something like that (I'm sure someone will correct me if i'm wrong)

Your battery runs at 14.4V when the car is running, 12V when it's not.

Im pretty sure ive got the 2ohm dual voice coil model. But do you think its better to get the 4ohm sub? If so im going to return this and get the 4 ohm.

Because the installer thinks to hook it up to 2ohm to the amp run 1000wrms to the sub from the amp and turn the gain down. He recomended the 2 ohm. But i would like to know what you guys think?

You %100 sure about "Your battery runs at 14.4V when the car is running, 12V when it's not." ?

If so im assuming it would be ok to run the full *1000 watts RMS x 1 at 2 ohms (14.4v) with the gain down?

Edited by DRFT31

Yeah you should be pulling around 14.4V be when the car is running (unless your altinator is on the way out).

If he sold you a dual 2ohm voice coil sub then no you can not run it at 2 ohm's and you should swap it for a dual 4ohm.

If he said that it WILL run at 2ohm's then he's sold you a dual 4ohm sub (which is what you want), or he's wrong :D

Hey guys update;

It's a SWR-1242D which is a 4Ω ohm sub, after opening the box which i shouldn't have to do. Thanks to the helpful audio SPECIALIST :P

What will be the best way to connect this sub, please in simple terms as im no expert lol....

Im wanting to get the most out of this sub as i know my amp could easily power this.

Do you guys think the 4ohm sub is better way to go or should i exchange for a 2 ohm?

Amp outputs 500wrms @ 4 ohm @ 12v. to my understanding when the engine is running, the alternator will (should) put out a bit over 14V, but what does the 12v mean?

Cheers :)

Edited by DRFT31

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