How to connect car subwoofers to computer?

[Gunslinger08]

I'm moving into a dorm next week, and I wanna figure out a way to connect my car subs to my computer (for that monstrous, dorm room shaking bass). I was wondering if anyone knew of a solution to this problem?

Josh

 

[Colt45]

computer ----> amp ---> subs

 

[Heisenberg]

You'll need an amplifier to power the subs. Then you just hook the computer up to the amplifier. Car subs are 4 ohm so you'll either need a car amp to power them or a home audio amp that's 4 ohm.

 

[dman]

Cheap (8ohm) home amp will work fine -- just get one powerful enough to drive the speakers. Run the Line out of sound card to amp line in. Then don't go crazy w/ volume or you'll overheat the amplifier, most will work OK w/ 4ohm loads though.

If you've got room for 2 of the subs, you can run 'em in series (mono) and drive 'em that way as an 8ohm load. Bass is not very directional sounding so you don't need stereo anyway.

Positive out from amp to positive of speaker A, negative of speaker A to Positive of Speaker B, Negative of Speaker B to Negative of Amp.

Been doing that with my home audio system for a while now. Actually, got Main Amp's subwoofer line out to a separate amp, which has the LR Inputs bridged and driving two 4ohm speakers in series. Frankenstein setup, but was cheap and works well. Speaker cabinets were on the cheap too.... bought some 12" diameter PVC Pipe from plumbing supply store (4' was like $20). Cut it in half and have 2x 2' bazooka tubes. (Had to cut some wood circles to cover the ends properly.

Speaker (woofer) specs didn't call for any venting, so, 2' length worked well. Speaker cabinet design is a whole other topic though so I'll stop here.

 

[d33pt]

just plug em into your soundcard's headphone output..it has a built in amp..

 

[Noriaki]

Originally posted by: d33pt
just plug em into your soundcard's headphone output..it has a built in amp..

Most sound card outputs are Line Level or "Pre"-outs.

And won't drive that. And even if you do have an actual Headphone amplified out, it's likely a pretty feeble amp and not going to drive a subwoofer very well.

I'd go Line out to amp to sub. That'll be safer on your soundcard, and give better sound. Even if it's a cheap amp.

 

[kt]

Get a power converter (AC to DC) to power your car amp. The line-out should be sufficient to provide a signal to the car amp input. I have seen some guy did this before. After he wreck his car, he took out all his audio components and put it in his room and built himself a home system with the parts. I gotta say, it's one sweet system.

 

[Adul]

keep the speakers away from the PC. the magnetic field of those things are very strong

 

[chiwawa626]

Yeah basicly Computer->Amp->Speakers/Subs, Um if i were you i'd just invest in good computer speakers, z560s if u want bass, or just get a mini home system...car subs are a lil bulky.

 

[Heisenberg]

You can use a standard 8 ohm amp to power them, but I generally like to avoid doing that. The impedance mismatch hurts the efficiency of the speakers which means the amp has to work that much harder to power them, and that increases heat output. But, like dman6666 said, if you don't get crazy and you don't really care about the amp that much, it will probably work.

The other route is using a car amp that requires DC. If you do that, make sure you find an AC to DC converter that can provide the current you need. A decent amp for subs is probably going to pull upwards of 10 amps easily. You need a hefty converter to supply that much current. If you can, get your hands on an old-school (and I mean old-school) computer power supply. Those things can provide enough power and have a nice clean output.

 

[bmacd]

dman6666 couldn't have said it better. Follow it exactly. For powering a car amp, i'd suggest going to RadioShack and picking up a regulated power supply to run a constant 12 volts to the amp (if you in fact decide to use a car amp). Umm...and like Adul said, keep the speakers a reasonable distance away from your computer/TV/VCR setups due to the large sized magnet on the back of the speakers.

Good luck...you know where to turn if something goes wrong

-=bmacd=-

 

[dman]

keep the speakers away from the PC. the magnetic field of those things are very strong

Worth repeating, absolutely true. Most car audio speakers (and most woofers for that matter) will drive TV's and monitors crazy... you'll get all kinds of color problems at the corners of the screens (usually). Most monitors and TV's have degaus circuitry built in, but, if the speakers are too close it will still be a problem.

The other route is using a car amp that requires DC. If you do that, make sure you find an AC to DC converter that can provide the current you need. A decent amp for subs is probably going to pull upwards of 10 amps easily. You need a hefty converter to supply that much current.

You can TRY a PC Powersupply's 12v line (I never have). I think there are issues w/ that-- PC uses more square wave then sine wave IIRC. Been a while. A car battery charger might work too... they put out 2-6+ amps @12v. Anyway, it gets expensive finding a cheap 12v supply w/ enough power so a cheap home audio amp is a good alternative.

 

[Heisenberg]

I wouldn't try it with a modern PC power supply but I have one from the 80's that actually has separate dual 6 inch cooling fans. It can put out close to 30 amps on the 12v line. The output from a computer supply is DC, so it shouldn't have any waveform - sine or square. DC from a computer supply is very clean. Unless you happen to stumble across one like I did then it probably is cheaper to buy a cheap home audio amp.

 

[Gunslinger08]

I need to figure out how exactly I'd hook up the amp to my soundcard. As you can see from my rig in my sig, I've got Logitech Z-560s already. But I want some more bass (yes, I'm crazy). I have a Soundblaster Live 5.1, so would I just connect the top jack (center channel/sub output) to the amp? I guess I'd have to find a 5' or so audio cable (1/8" jacks on both ends), and then buy something to convert from 1/8" to RCA.

About the 12V DC power source.. anyone know of a place to find these online?

I can't drive for my car on campus this year, so I may as well get some use from the subs.

Josh

 

[dman]

Originally posted by: Heisenberg
I wouldn't try it with a modern PC power supply but I have one from the 80's that actually has separate dual 6 inch cooling fans. It can put out close to 30 amps on the 12v line. The output from a computer supply is DC, so it shouldn't have any waveform - sine or square.

D'oh, so true! I Don't know, I just remember there was something about a PC Supply not being suited for car audio that I never really tried it, but, I suspect it'd work anyway.

it probably is cheaper to buy a cheap home audio amp.

For Example, This would do just the trick.