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Discussion Starter · #1 ·
"The Plan" before the question:
2009 w/factory Bose
Replace the HU w/Alpine 505 and replace the Bose amp with Alpine MRA-F350

Ok, so from searching around I believe I have come to the conclusion that the factory Bose system contains 2 ohm speakers. If this is in fact the case, would I be able to replace the Bose Amp with an Amp rated at 50 watts RMS x 5 @ 4 ohms? I'm not sure if the ohms have to match up, but I feel like that might be important. Under features and specs for the Alpine amp there is nothing listed for "Power at 2 ohms", however it does NOT say "N/A", there is just nothing there. Does that mean 2 ohms is not an option?

My next question only applies if I can use this amp with these speakers.

The factory Bose system says its a 7 speaker system. I'm going to assume that the speakers that make the 7 speakers are:
2 tweeters near windows on front doors
2 in the front doors
2 in the rear doors
1 "subwoofer"

If this is the case, then with the 5 channel amp that I plan to use, where would the tweeters come into play?

I figure I would use:

-the front R & L spots on the amp for the respective front door speakers
-the rear Rs & Ls spots on the amp for the respective rear door speakers
-the center channel spot on the amp for a cc speaker that I would buy

How would I hook the tweeters up? Or would I just write those off as a loss with the "subwoofer"?

Thanks for any help, and I'm sure I'll have more questions to come.

-Sean
 

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tweeters get tied into the fronts with a crossover. the stock system uses a capacitor in place of a crossover.
 

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Discussion Starter · #3 ·
But the wattage from the Alpine amp would be doubled to the Bose speakers, is that correct? Therefor I would be sending 100 watts to each speaker? Am I understanding this right? If that is the case, then obviously I would blow the Bose in a second. Is there any way to prevent this, or do I just need to replace all of the speakers?

-Sean
 

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should just go ahead and replace them anyhow, they're crap...
 

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not sure if you still have the questions but if so id like to find out more about what your planning on... if you get a new head unit i wouldnt put in a five channel amp. i wouldnt put in an amp at all unless your planning on replacing the speakers.

my view of the bose is a negative one. i will soon be ripping out ever audio component that came in my three and doing a full upgrade... but again, i wouldnt bother putting in a amp for the stock speakers since you have an amp already in the car under the passenger seat, unless you replace the speakers...
 

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don't worry about blowing the bose speakers with too much power, as long as you set the gain right you will be fine. You WILL want to replace the BOSE speakers asap though, the fronts in particular - get a decent set of components.

That amp is a little light in terms of power, but given that is specifically designed for dolby digital it might be ok if that is the main reason you picked it. If you are not going to add a center channel then I's ditch the whole dolby idea and got with a larger 4 channel . Another option is to get a seperate DD processor like the PXA-H701 and get all the benefits of a great eq and crossover to go along with the decoding, and you can use it with any amps you like.
 

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Discussion Starter · #7 ·
Thanks for the help! Yeah, I'm wanting to have 5.1 so that movies have the full effect. It seems that replacing the factory speakers will be a must before the project is done though, huh? As far as components go, the only install I have seen for the 3 required the crossovers to be in the pockets of the doors visible inside the cabin. How do components work, would I be able to put the crossovers somewhere with the amps and just run longer cables from the crossovers to the speakers, that way they would be hidden? I'm not sure I understand about the stand-alone DD processor, I will look more into it, but are you saying that I would be able to use one of these with the factory Bose and not have to replace the speakers? Thanks again guys!

-Sean
 

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the speakers just need to be replaced because they're crap, not because the amp can't handle them or vice versa - it can just fine.

The processor takes the digital input from the headunit and decodes the DD/DTS streams, adds EQ and crossover processing and then outputs it as front, rear, center and sub RCA's which can plug into any aftermarket amp (not the bose amp). The amp you linked has a very simple version of this processor built into it, but you lose some of the processing power and the ability to pick (or upgrade) the amp that best fits your speakers.

http://www.crutchfield.com/S-xXjbKF5RvaJ/p_500PXAH701/Alpine-PXA-H701.html?tp=84

to be honest it's getting hard to find now that it's discontinued though
 

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you can do soemthing similar with pioneer's
http://www.pioneerelectronics.com/PUSA/Products/CarAudioVideo/Source/AV-Receivers/AVH-P6000DVD
along with
http://www.pioneerelectronics.com/PUSA/Products/CarAudioVideo/Accessories/Audio+Components/DEQ-P8000

this combo has slimmed down features of what the alpine has but is cheaper and easier to find

or
http://www.pioneerelectronics.com/PUSA/Products/CarAudioVideo/Source/AV-Receivers/AVH-P7800DVD
which has all the processing built right in for 6.1 audio and a higher definition screen

all of these options ( and others) will work, including the original amp you mentioned - it just depends on how much flexibility you want.
 
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