Need advice on hooking up car audio system

[kramytech]

I don't really understand Ohms very much. Over the last year or so, I have bought the following car audio parts on sale (mostly from best Buy deals-of-the-day) for a 2013 Ford Focus ST I will be getting within the next couple of weeks or so.

Deck - Sony CDXGT56UI - 52W x 4 Apple® iPod®-/Satellite Radio-Ready In-Dash CD Deck

Amp - Alpine MRX-V70 - MRX Series 710W Class D Digital Multichannel Amplifier

Subwoofer - Pioneer TS-W309D2 - 12" Dual-Voice-Coil 2-Ohm Subwoofer

Door Speakers (2 sets) - Polk Audio DXI650 - 6-1/2" Coaxial Loudspeakers with Poly-Mica Cones

Amp Control - Alpine RUX-KNOB - Remote Subwoofer Control Knob for Select Alpine Amplifiers

Subwoofer Box - Metra TCBXP-112 - 12" Single Ported Subwoofer Enclosure

I plan on having Best Buy install these parts in the car, but I am not 100% sure that they would know the best way to hook the speakers up to the amp correctly.

Is it better to hook everything up at 4 ohms, or hook the sub up at 2 ohms and the 4 door speakers up at 4 ohms, etc. ?

I care more about the quality of the music than I do about the volume level.

What does anyone recommend as the best way to hook everything up?

Any suggestions would be much appreciated.

Thanks //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

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[bradl79 10+ year member]

recommend not to have best buy install it, unless u have the money, they will charge prob over 700.00 to do it, if u do a local shop they may charge less

 

[Jepalan]

You have a 5-channel amp, so the 2 sets of Polks will get connected to 4 channels of the amp normally. You can't "bridge" these outputs because you don't have enough channels, so there is no "ohms decision" to make here.

The sub will connect to the 5th channel. Unfortunately this sub isn't a good match to your amp. You would have been better off with a DVC 4-ohm sub for this amp, then you could get max power out by running 2 ohms load. That said, there is only one "right" way to connect this sub to your amp. The voice-coils should be wired in series for 4-ohms.

 

[kramytech]

Thanks for the info. I looked at my amp and it says it is "1 ohm stable". What does that mean exactly? Also, here is a diagam I got from the Rockford Fosgate site

View attachment 26543956

rockfordfosgate.com/support/

It shows how to hook up a DVC 2-ohm sub either at 1-ohm or 4 ohms. Which would produce better sound quality? And is my amp/subwoofer even capable of hooking up at 1 ohm?

 

[profundus-sanus 10+ year member]

Thanks for the info. I looked at my amp and it says it is "1 ohm stable". What does that mean exactly? Also, here is a diagam I got from the Rockford Fosgate site
View attachment 26543956

rockfordfosgate.com/support/

It shows how to hook up a DVC 2-ohm sub either at 1-ohm or 4 ohms. Which would produce better sound quality? And is my amp/subwoofer even capable of hooking up at 1 ohm?

are you sure it's 1 ohm stable. i just looked everywhere and it shows 2 ohm stable.

1 ohm stable means 1 ohm is the minimum impedance it can run. The lower the impedance, or ohms, you run the more stress it puts on the amp. But also, most amps make more power when the impedance is lower as well.

 

[bbeljefe]

Where are you? Maybe someone here can help you out with the install and save you high labor costs.

Also, that amp isn't one ohm stable.

 

[Jepalan]

Thanks for the info. I looked at my amp and it says it is "1 ohm stable". What does that mean exactly? Also, here is a diagam I got from the Rockford Fosgate site
View attachment 26543956

rockfordfosgate.com/support/

It shows how to hook up a DVC 2-ohm sub either at 1-ohm or 4 ohms. Which would produce better sound quality? And is my amp/subwoofer even capable of hooking up at 1 ohm?

Your amp (MRX-V70) is not 1 ohm stable. Here is the manual: http://a248.e.akamai.net/pix.crutchfield.com/Manuals/500/500MRXV70.PDF

If it was 1-ohm stable then you could wire your VCs in parallel to get the most out of it. Since it is not 1-ohm stable, you will likely blow the amp if you wire for 1-ohm.

Please show me a link or pic of the "1-ohm stable" spec for your amp if I am wrong on that point. Thanks.

 

[kramytech]

Here you go. It actually says it is "1-ohm stable" on the Best Buy website. (I am learning that is not the most reliable place for electronics information. You would just assume that they would not put incorrect information about their products on there)

View attachment 26543959

Thanks guys for verifying this information

 

[kramytech]

I am in North-East Texas. I think that the Geek Squad stereo installation pricing at Best Buy is around the same price as the professional stereo installation places around here.

Yeah the amp being 1-ohm stable information came from the Best Buy website (obviously wrong information)

Thanks

 

[SounDrive Pro Seller]

The 5th channel may be 1 ohm stable, I've seen several amps like that. Not sure about this specific one, though.

EDIT: not 1 ohm stable

 

[Jes 42 10+ year member]

From the Alpine site-

CEA-2006 Power Rating: 60W x 4 + 250W x 1 (4 0hm@14.4V = 0.10%THD+N), 90W x 4 + 350W x 1 (2 0hm@14.4V) S/N 86dBA (Ref. 1W into 4Ohm)

60 Watts x 4 + 250 Watts x 1 into 4 Ohms

90 Watts x 4 + 350 Watts x 1 into 2 Ohms