Thread: Speaker Power Question

Originally Posted by ssa_whiskey

Hey guys, first I'd like to say thanks for all the help I've gotten here from reading this forum, and secondly, this is my first post, and certainly my first thread start. The question of the day is this: Can a speaker, namely one designed for a car, be used with ac power? Will alternating current damage the speaker cone in any way or affect its performance? Is it safe, or a bad idea? I'm wanting to use car speakers in my room for my puter- I know this isn't for a carputer (but we are making one for my friend's camry) , but I cant find just a speaker for home use that isn't sold with a box attached or nething else like that. I also think that car speakers look far better than any home speaker that i have in my house.
notes*- ill prolly use pioneer premiere 6.5 and or 3 inch tweeters on ac current., the voltage will be dropped, im using the internal amp from my original puter speakers, or the amp i got at radio shack for bout $60. thanks for all of your help, specially with the fiberglassing tips and info

Well, here's the thing. All speakers are pretty much DC. Positive/negative. If you apply AC voltage direct to the speakers, you will get a 60hz hum from them right before they blow out and possibly catch fire just to get back at you for doing that to them!

Amps provide power in standard DC to the speakers. The question I think you need to ask is will the Amp take AC... The best way to drive your speakers is to connect them to a home receiver. At that point you need to be concerned about the resistance (ohms) the speakers offer. Most home stereos are about 8ohms (4 for the better ones!). If your speakers are 2ohm, you could end up damaging them in the long run on the receiver. Try to match the impedence (resistance, ohms whatever) of the receiver and the speakers.

Lastly, make sure that your source does not exceed what your speakers can handle. In essence, do not connect 85watt speakers to a 150watt stereo!

I use 4 10" car speakers in my home rig. They seem to work just fine.

A car amp on the other hand, was designed for DC, NOT AC. It will burn quicker than anything if you plug it into the house outlet!

So let's review:

1) If impedence doesn't match between speaker and stereo, don't worry too much, just don't turn the sound up too far.

2) Do NOT apply AC power to the speakers directly

3) Do NOT apply AC power to the amplifier from your car

4) Make sure the receiver you connect the speakers to doesn't overpower your speakers.

Class dismissed. I need more pizza.

Hope I could help!

I have no idea what either of you are talking about...

Speakers are electromagnets with a audio cone connected to produce sound when an electrical input between 20hz and 20,000hz is applied...and hz means cycles per second...that means AC.

Now speakers with built in amplifiers may be made for AC (like the sub in my house) or DC (like the add-on subs for cars)

A stand alone speaker element can be driven by any amplifier audio or otherwise...every speaker has a maximum input allowance...in watts...doesn't matter how the watts are applied.

So lets limit the discussion.

You have a home receiver...yes you can hook your car speakers too it...just be careful on the power.

You have a car stereo...yes you can hook your house speakers up to it.

While we are on over powering car speakers.. I am getting two JL 10W6v2's, which are 400wRMS each (1ohm total based on how I wire them). I am looking at a JBL 1200wRMS @ 1ohm amp for them. Will this be a bad thing becuase of the said overpowering? If so, any suggustions on a 800wRMS amp? I don't want to underpower these subs, and so if over powering them is safe then I'll do it, or if someone can show me a 800wRMS amp

Originally Posted by ssa_whiskey

thnx guys, that clears it up, but one more ? just to be sure....

it is known now that they will work if properly regulated ie. not too many ohms or power. now i have an amp, that i assume converts ac to dc and then powers my speakers, also the computer speakers that are p.o.s. have a built in amp with a power convertor from ac to dc, what i want to do is use an amp to power the much better sounding car speakers that i can buy for cheaper than any home of relatively any quality...

question is this: how do i tell how many ohms that the amps in the already existing speakers have, will it say it somewhere or should i just guess? and how can i up/down convert to match them if they are not the same?
-thnx for the help

There are three primary impedence levels used in audio: 8ohms, 4ohms, and 2ohms. There are 1ohm setups out there, but they're not mainstream as far as I know. The lower the number, the lower the bass the speakers are able to produce. You can connect a set of 4 ohm speakers to a standard 8ohm home receiver without much issue, but try to be sure that the signal source is not lower than the speaks, or it will be trying to push lower frequencies than the speakers are capable of handling, and though it will not immediately hurt them, will likely shorten their lives. Most car audio amps produce 2ohms, tho some lower quality ones do 4. Either way, you should be safe with what you're talking about.

DodgeCummins, I was a little confused as to what exactly he was considering connecting to AC, so I covered both bases with the amp and speakers. I wanted to make sure he was aware that connecting either to AC, when they were originally installed in a car, would be a bad idea.
I'm a little jumped on a sugar buzz, so it's entirely possible I wasn't too clear on my first post... Hehehehe... Please forgive if so...

deadweasel - So IYO, I would be better off wireing my subs so they use 4ohm vs 1ohm?

Originally Posted by SiGmA_X

deadweasel - So IYO, I would be better off wireing my subs so they use 4ohm vs 1ohm?

Well that depends on what your speaks can handle!

If you try to push lower (lower ohms) than what they can handle, you will inevitably kill the cones. The voice coils will start bottom out (the speakers are moving too far for their design). If you have 2 ohm speakers, I would keep the wiring setup for 2ohms. Now if your amp is at 4, it might be better to leave it that way too. At least that way, you might not be driving the speakers to their fullest, but you won't be in danger of farking them right over! Besides, you could always get a 2ohm amp later on.

As far as re-rigging existing units, that's where my experience gets a little grey. I just know how to keep stuff happy, and that's about it!

These are JL Audio 10W6v2's, and can handel the 1ohm load in what I wire. I am looking to buy a 1200wRMS @ 2/1ohm's amp because these subs can do 1ohm and so can the amp. Or, should I run the subs at 4ohm's? What is better for the sound quality, 1 or 4ohm's? I can do it either way..

Originally Posted by SiGmA_X

These are JL Audio 10W6v2's, and can handel the 1ohm load in what I wire. I am looking to buy a 1200wRMS @ 2/1ohm's amp because these subs can do 1ohm and so can the amp. Or, should I run the subs at 4ohm's? What is better for the sound quality, 1 or 4ohm's? I can do it either way..

Oh hell! If they were built for it, then DO it!! Dude, you got teh ****z to make some crazy low sound! If it's all meant to be able to do 1ohm, then pump it!