# Home Theatre with car subwoofers



## d_hubert (Dec 28, 2006)

First time poster but i was just looking into hooking up my old car sub woofers to a home theater system i was about to purchase. The subs are 10'' 500 watt max 4 ohm pioneers and the guy at best buy who seemingly knew what he was talking about said i would only need the home theater system, and an AC/DC converter to power my old amp to supply additional power to the subs. i figured i would ask some others who know what they are talking about before i started rewiring the room. Thanks in advance


----------



## Frank4d (Sep 10, 2006)

I would not trust anybody at Best Buy to know what they are talking about. That said, what home theatre amp or receiver/amp are you buying? And what other speakers?


----------



## kiwiguy (Aug 17, 2003)

The "AC/DC" unit to power the sub amp is probably the hard part.

You are looking at around 20 to 80 amps of 12v pure DC here, that will not come cheap.


----------



## d_hubert (Dec 28, 2006)

I was looking at an amp around the 400 dollar range but my search has yielded no results in going to best buy, circuit city, PC richards and a local HT store. in speaking with 1 worker he said that i would need a 5.2 system as opposed to a 5.1 since i wanted to hook up 2 woofers. Why can't i just find an old school amp with speaker wire inputs as opposed to the new amps that are all RCA jacks for 1 woofer. I know i could splice the wires together but that would half the power to each speaker. The Hi's i'm not so worried about i have some around the house that i can use and they are decent.


----------



## kiwiguy (Aug 17, 2003)

"Splicing wires" will also halve (or double) the impedance of the speakers, so you are best to avoid that.

Putting them in parallel gives 2 ohms which would probably destroy an amplifier, putting them in series would give 8 ohms, which is more acceptable (depending on what the amplifier used is rated at) but may introduce some other distortions.

You may also be confusing "amplified speakers" (RCA fittings) with real "speakers" (2 wires)?

Your 500 Watt subs are real speakers, you need a humongously rated amplifier for them (and no neighbors).


----------



## d_hubert (Dec 28, 2006)

It would be speaker wire if i came from the box directly to the amp i want to purchase. It would be rca cables if i went from the box, to my old car amp, then to the new amp. I'm trying to find the easier and cheaper method to achieve my goal. i was told that a small AC/DC converter would power the old car amp but i was extremely skeptical. here's the product specs on the converter : 

Travel Mate, 6.0A, AC/DC Converter, Instantly Converts 110V AC Current Into 12V DC, Operates On Standard Household 110V Current, Auto Thermal & Overload Shutdown, Extends The Convenience Of Your 12V Devices, Plugs Into Any Standard 110V AC Outlet.

i figure it is to good to be true that something that would cost me 20 bucks could solve my problem


----------



## kiwiguy (Aug 17, 2003)

6 amps at 12 volts = 72 watts.

You do not mention the rating of the car sub amp, but if the speakers are rated at 500 Watts, it is an indication.

200 to 500 Watt sub amps are common, that is a hell of a long way from 72 Watts though.

500 Watts at 12 volts is 42 amps.


----------



## d_hubert (Dec 28, 2006)

http://www.pioneerelectronics.com/p....html?compName=PNA_V3_ProductDetailsComponent

I have 2 of those it's rated up to 500 watts at 4 ohms. I knew that guy at best buy was a moron. I wish i still had my old job so i could get all this stuff really cheap instead of going through these stores. I have an old 300 watt amp laying around the house so i think i'll try to just hook that up to the speakers directly and see if the bass hits and if it works i'll scrape up some hi's. Thanks a bunch for the fast replies and help Kiwi i appreciate it.


----------



## kiwiguy (Aug 17, 2003)

Just watch the impedance as above. Do not connect then in parallel, check what impedance the "old 300 Watt" amp expects, if it's a domestic one it probably expects 8 ohms per channel it may rupture its guts on 4 ohms per channel.


----------

