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Discussion Starter #1
will 8OHM impendance subwoofers work on our cars??
(mazda 6s)
non bose

EDIT: thought i was in noob section, feel free to move it.
 

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no, can't do 8 ohms. only 2 or 4. what kind of speakers u got? (also depends on how u wire the speakers)

btw, bridged means using the positive terminal of one channel and the negative terminal of the other channel to acquire total max power to one speaker. if u just use one channel u will only get half of the total output of wattage that u can get from the amp. (u have a 2 channel amp, right?).

also...NEVER buy brands that u have never heard of when it comes to stereo equipment, especially amps.
 

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they'll work. what i meant about buying brands u never heard of was directed at buying from ebay. i had a friend who thought she was getting a 800 watt amp from some unheard of brand, came in and when we tried to install it it sounded like shit. then it started to sizzle and smoke...
i guess it's worth a shot since it's pretty cheap, and it's from best buy, i guess u could return it if u don't like it. is your car set up for an amplifier? (i.e. do u have all the wiring and shit done?) if you're gonna run it off the stock stereo of the 6 u need some kind of signal converter, i forget what it's called tho, should be around $30.
 

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Discussion Starter #7
im pretty good with electronics within the car but IVE NEVER EVER done any audio stuff in my life. I took a look at the trunk and figured where the wires are goign to go and all that crap, but i havent done anything. I have a $40 bestbuy gift card so thats what im using to buy some of the wiring and crap like that. But i have none of the wires set up yet or converter.

Any websites you got??

O and by the way i have a crap load of 12 guage wire laying around my house, could i use that stuff for some wiring?

help me out here.

another member is selling some kole audio stuff. tell me what you think about that. 980 watt sub and an amp and a custom sub box. Is this good quality? never heard of kole.

(( o and none of the stuff is wired up yet.. for my setup i was thinkin about))
 

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You can drive an 8 ohm sub with just about any sub amp. The ohm rating of a speaker is a measure of resistance to the flow of electricity. The more resistance you have, the less power you will have. An 8 ohm sub will "extract" half the power from your amplifier as a 4 ohm sub would. An 8 ohm load is a very easy load on most amplifiers.

Assuming that the subs are 8 ohms each, your best bet with that sub / amp combination would be to bridge the amp, and then drive both subs in parallel. The two 8 ohm subs would sum to a 4 ohm load, allowing you to get more power out of the amp.

Have a look here for some decent info:
http://www.carstereo.com/help/Articles.cfm

Also - regarding the wire - 12 awg should be fine for connecting the subs to the amp, but you really should use 8 awg or larger for the power & ground connection to the amp.

Good luck!
 

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Discussion Starter #9
ok so this setup will be compatible with my car?? correct? no special things needed that will cost me $100 extra bucks [besides wiring of course]

i dont need the metra kit do i?
 

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If you're using the stock non-bose head unit, you will also need a line-out converter (since that amp doesn't have speaker-level inputs). Or you can make a simple voltage divider circuit with a couple of resistors (see here: http://en.wikipedia.org/wiki/Voltage_divider).

I suggest connecting the subs to the FRONT channels, as the rear channels do not output a full range signal. You will have less than stellar sound from your subs if you connect to the rears.
 

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Discussion Starter #11
jeeeez im so confused. there is no write up on this im guessing?

any chance you could make a shopping list of things ill need ( you dont have to include prices just things ill need )

obviously these 3

amp
2 (subs)
2 (sub boxes)

.... ok wat else like wat kind of wires and converters ect.
 

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jeeeez im so confused. there is no write up on this im guessing?

any chance you could make a shopping list of things ill need ( you dont have to include prices just things ill need )

obviously these 3

amp
2 (subs)
2 (sub boxes)

.... ok wat else like wat kind of wires and converters ect.
[/b]
At a high-level, you will definitely need:

- Amp
- Sub(s)
- Box(es)
- Line out converter
- Wiring kit

The wiring kit should include a power wire to run to the battery, an inline fuse, a ground wire, a "remote" wire which will be connected to a switched +12v signal, a set of RCA cables, and speaker wires.

If you feel like you're in over your head, I suggest you find a friend who can help you or take it to a professional installer. Botched wiring can be dangerous. It can damage equipment, or worse - start fires.
 

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Discussion Starter #13
These were all of the amp installation kits i found that were decently priced: (descending in price )

i found this but it doesnt include RCA cables
http://www.bestbuy.com/site/olspage.jsp?sk...d=1134701342408

and (which looked ok)

http://www.circuitcity.com/ssm/Tsunami-Amp...tDetail.do#tabs

and

(this looked like a steal)
http://www.amazon.com/1000-Watt-Amplifier-...p;s=electronics

last but actually looks like the best is
http://www.amazon.com/AMPLIFIER-INSTALLATI...p;s=electronics

tell me what you think.
definately open to recomendations.
 

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At a high-level, you will definitely need:

- Amp
- Sub(s)
- Box(es)
- Line out converter
- Wiring kit

The wiring kit should include a power wire to run to the battery, an inline fuse, a ground wire, a "remote" wire which will be connected to a switched +12v signal, a set of RCA cables, and speaker wires.

If you feel like you're in over your head, I suggest you find a friend who can help you or take it to a professional installer. Botched wiring can be dangerous. It can damage equipment, or worse - start fires.
[/b]
The above is correct in terms of parts you'll need. Here's a bit of detail as to what they're for, and what has to be done:

Music Signal to Sub Amp:
Line Out Converter (LOC) - goes between head unit (CD player/radio) and sub amp, provides very low voltage hi quality music signal to amp (this is different from the power signal that goes to the speakers). You'll need to find out what wires on the HU to connect this to. Search the forum as I think it's well covered.
You'll have to somehow connect the wires from the LOC to the HU. This usually involves using some type of wire tap or soldering (more skill required). Again search this forum for connecting LOC. The RCA cables will be used to connect the LOC to the Sub Amp.
Head Unit >wire taps or solder> Line Out Converter >RCA cables> Sub Amp

Power to Sub Amp:
+12 (thick red wire) from +ve battery terminal, with inline fuse (put near battery) to Sub Amp
Ground (thick black wire) from Sub Amp to some solid metal part of the car (scrape paint away) or from -ve battery terminal
Switched +12V (thin wire, could be red or whatever color) from HU to Sub Amp; this tells Sub Amp to turn on when HU is turned on. If you drive with the stereo on all the time and never turn it off you can connect to a switched wire in the ignition or the cigarette lighter (if it's not powered all the time - test it to see that it doesnt' work when the car is off). This means the Sub Amp is on anytime the car is on. You don't want the Sub Amp on permanently, even when the car is turned off.

Sub Amp to dual 8ohm Sub Woofers:
Hook the two 8 ohm subwoofers in parallel. Identify the positive and negative terminals on the subs. Connect the positives to each other, and the negatives to each other. Use thick (heavy gauge) speaker wire. You can do this by running the speaker wire inside the box and connecting up the terminals to each sub before screwing them in. Use another piece of speaker wire to connect to the terminal panel on the subwoofer box.
Alternatively, or if the subwoofer box doesn't have a terminal plate but just a hole for the speaker wire, you can run speaker wire from the Sub Amp directly to each subwoofer. Be sure to maintain the correct polariry, positive to positive and negative to negative. In this case you will have 2 sets of speaker wire, one going to each subwoofer.

Because the subs are 8 ohms they will still only draw half the power that a 4 ohm speaker would. But, with two subs both drawing half power you are now making the amp deliver the full power it's capable of with a 4 ohm load.

Keep in mind that power handling and power output is only one small and relatively insufficient measure of overall performance. Of greater value and interest would be sensitivity of the speaker, ie how much sound pressure level (SPL) it can generate with a given power input. Standard is 2.83V at 1 meter; for our purposes consider it to be 1 watt of power.
A subwoofer that has 92dB sensitivity will generate the same SPL but at only half the power of an 89dB sensitivity subwoofer. Try to find speakers that have high sensitivity ratings. They'll play louder with less power. Also, always check frequency response (given as low freq to high freq, with stated max variation, eg 25Hz - 18kHz, + 3dB), and total harmonic distortion (given as %, eg. 0.05% THD)
There are other criteria, such as dynamic current capability (how much current the amp can deliver when a sudden loud music spike is sent through, such as a drum strike), slew rate, damping factor, etc, etc, but it would take more time than I have to explain them here.

Hope this helped. If the above sounds confusing and more than you want to tackle, take the advice others have provided and have a professional install it. It's worth it in the long run, both in quality of sound and reliability/safety. I've seen a car go up in flames due to poor electrical work; it goes up really fast and you do not want to be anywhere near the car when it starts to burn, much less in it.
 

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Discussion Starter #16
this is kinda a double post but i returned my amp and subs and im purchasing a pioneer system. It frees up trunk space (only 1 sub) and its a 600 Watt sub so i can put out a litte more power than before. Also i have a 760 Watt amp.
 
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