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4 ohm Home audio speakers in car ???

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Old Dec 17, 2010 | 09:42 PM
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4 ohm Home audio speakers in car ???

Hi guys, I am new to car audio. I have been purchasing lots of consumer speakers from crutch field, and i keep sending them back... long story short i have a pdx 5 amp, a p3d412 sub and no speakers currently. The amp is rated at 75 watts rms to four channels or 150 bridged. i have been looking at all the brands mentioned here ( dls, rainbow etc.) and I think I am more interested in using home audio speakers in my car. I am hoping that one of you guru's will help me out with what to buy... woofers, tweeters, cross overs and placement. I am hoping to fabricate some adapters for the woofers and get them into my chevy malibu. As far as i know, the pdx 5 requires the speakers to be 2-4 ohms.

I can see this is an older thread, so i will start a new on the topic. Any assistance would be SOOOOOOO APPRECIATED!!!!!!! I can't stand driving my car with out music, so i am hoping someone can help me get a game plan together asap.

My background with audio reproduction is mostly studio monitors, but i do have a set of polk rti6's (which i like the sound of). I only started this project to get my car to sound a little more like the various speakers/ monitors i use at home on a daily basis.

HOPEFUL SETUP:
- a set of 2-ways in the front stage @ 150 rms each
OR
- a set of 2 ways in both the front and rear at 75 watts rms each

Thanks in Advance car audio guru's!!!!!!
Old Dec 18, 2010 | 09:43 AM
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Now my understanding is that passive means un-amped and active means amped... does this apply to the car audio world? All of this talk about running passive or not passive speakers is kinda of confusing me.
Once again any help on the topic would be useful.

Thanks guys!
Old Dec 18, 2010 | 10:41 AM
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Running passive means using a single amplifier channel to run more than one speaker through a passive crossover.

Running active means using an electronic crossover and having an amplifier channel for each speaker.

Aside from the potential issue of longevity with untreated paper cones in some home drivers, there is no problem at all in using them in a car. The selection is immense so you have some work ahead of you.
Old Dec 18, 2010 | 10:57 AM
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Parts-Express.com sells Speakers, Replacement Speakers, Speaker Building Parts plus HDMI Cables, Home Audio and Video, Pro Audio and Commercial Sound. We offer services for Speaker Reconing, Speaker Refoaming, Speaker Repair. Great selection of Elect

solen.ca

Madisound Speaker Components | Assisting speaker builders for more than 25 years.
Old Dec 18, 2010 | 10:59 AM
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Thanks Dukk,
That explained a lot, I am starting to see just how much it would be. Just grabbing the first component set that comes my way is starting to sound very tempting.
Old Dec 18, 2010 | 11:06 AM
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Originally Posted by sheathensemble
Now my understanding is that passive means un-amped and active means amped... does this apply to the car audio world? All of this talk about running passive or not passive speakers is kinda of confusing me.
Once again any help on the topic would be useful.

Thanks guys!
Not exactly, it refers to the crossover type.
Passive crossovers are installed between the amplifier and speakers in the system. They require no power hookup which is why they are called "passive". Passive crossovers limit the program played by each driver to a limited frequency band. Their frequency bands are usually fixed value and tuning them requires transplanting parts.
Benefits:
Cost: parts are generally cheap and only one amp is required for all drivers.
Simple: mount it, hook up wires from amp and each speaker and you're done.
Downside:
Tuning: requires transplanting parts which is time consuming
Quality: values drift with temperature and age, damping factor is compromised.

Active crossovers are powered (hence the "active" designation) and are installed before the amplifier(s). Active crossovers limit the program played by each amplifier to a limited frequency band. The limits are usually adjustable on-the-fly which makes tuning easier and allows easy tweaking later when upgrading.
Benefits:
Tuning: easy as turning a **** and can usually be done on-the-fly.
Quality: damping factor improved since driver is connected directly to amp, each amp plays a narrow frequency band so spectral power is lower (fancy way of saying more headroom is available in the intended band).
Downside:
Cost: multiple amps get expensive, crossover itself can be more costly too.
Complexity: power wires needed, extra interconnects needed, real estate (multiple amps to install)

I replied to your PM but I suggest continuing the discussion here so others can read your progress down the road. I don't mind the PMs but maybe this could be helpful to others

Last edited by kevmurray; Jan 6, 2011 at 06:54 PM. Reason: drunk
Old Dec 18, 2010 | 11:23 AM
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Well the thought of having multiple amps is really what's stressing me the most. I bought the pdx 5 so i would haven't have to use more than one (doh). And installing multiple amps would mean I would need to upgrade my power supply. I think i should of really done this research before getting stuck with a 5 channel amp.

But for the record:


Hifonics HFXR - Crossovers - Sonic Electronix

So is this (check link above) an active crossover? are "electrical" cross over the same thing? also i have purchased a clarion eq, Haven't received it yet, but can I hook both active crossover and a external eq up to my head unit? i am using a Kenwood KDC-MP745U (6 channel rca output)

Thanks again guys! I have never had received responses so quickly in a forum before. I think the fact that this a Canadian forum is the primary reason for that. We are such helpful ppl!

Thanks again,

Rod
Old Dec 18, 2010 | 11:31 AM
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Your amp is fine, multiple channels is the same thing. However if you bridge the four channels to two you will need another one for your tweeters.

Edit: yes that link is an active crossover and "electrical" ones are probably the same thing. They are sometimes called electronic crossovers. You can use it with an EQ.

Last edited by kevmurray; Dec 18, 2010 at 11:34 AM. Reason: addition
Old Dec 18, 2010 | 06:19 PM
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ok, so i have been shopping around all day, I think i have found a woofer and tweeter that i could pair up. the crossover would have to be at 1800 hz. I have been looking at passive crossovers and all day and they never tell you where the crossover point is... am I missing something? do passive crossovers have a dial that you use to set the crossover? i was looking into 3-ways as well but i have had a hard time finding a midrange speaker that lines up with the woofer and tweeter i have narrowed it down to.

Here's what i have found:
woofer: Dayton RS180-4 7" Reference Woofer 4 Ohm | Parts-Express.com

tweeter: Dayton RS28F-4 1-1/8" Silk Dome Tweeter | Parts-Express.com
let me know what you think

Thanks guys!
Old Dec 18, 2010 | 07:01 PM
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I thought you already had a woofer? As far as those choices go they are great drivers but you would need a crossover with a very steep roll off. Something like LR24 (4th order Linkwitz Riley). If you want an active crossover this is not too hard to find but an off-the-shelf passive would be. You could always make your own passive of course. A three way would not be hard with these two drivers as they pretty much overlap as is. You just need a midrange and crossover. A crossover for a three way would not need the steep slope. Addison has some off-the-shelf crossovers you might consider. You could even customize one for your purpose.



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