Home audio drivers vs. car audio drivers

Drew: To those that understand what Fs, Qts and impedane mean, they will understand exactly what you're getting at. For those that are reading this, it probably went right over their heads : )

Speakers are designed very differently as they have very different atmosphere's ( acoustically and environmentally ) to deal with.

Amplifiers are designed very differently as they have a very different power source to deal with.

Having said that, you can get "pretty decent" car audio gear for not that much money. Just like in home audio, you have "pretenders to the throne" who rely on hype, cosmetics and fictitious spec's and then you have "the real deal" type of components that are built and designed around real world operating conditions and environments. Guess which type of product is most likely to be found in the majority of "boom boom" vehicles heading down the road. If you're not sure, just think about how much Pioneer / Sony / Kenwood type stuff you see in home audio as compared to even Parasound, Adcom, NAD, etc.. type gear. This is not to mention the likes of "audio standards" such as ARC, Krell, Pass, etc...

Cheaper junk that promises you the best for the least amount of money is what keeps the economy alive. People buy cheap junk, find out exactly how junky it is and then sell it to buy the next higher level of junk. Without all of the low grade junk and the learning experiences involved, we wouldn't have a "High End" in either home or car audio. It's just too bad we can't to how "junky" the low grade "junk" really is : ) Sean
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PS... Most car audio subwoofers are designed for maximum output at higher frequencies with little concern for extension and / or linearity. This results in more apparent bass, which is why you hear "boom, boom boom" or "thud, thud, thud" rather than musical notes. Then again, most of the recordings that have that "boom, chukka, splash" on them isn't very "musical" to begin with : )

LOL @ Slappy correcting himself.

In the early '80s I used a lot of home speaker components in my car.

One of my favorites was a home ribbon tweeter I got at a local electronics shop. It was extended, but not bright, but it was a bit on the dry side.

I also enjoyed ADS and Boston Acoustics separate speakers from that era.

I remember when Nakamichi and KEF came out with car audio components my friends and I got excited because we thought some of the home audio tech, and quality would migrate to the car scene. But in general, I wasn't too impressed with their initial offerings.

My faovrite speaker combo was one I Frankensteined together along with a homemade three-way crossover. and all 8ohm drivers. It sounded much more musical than anything I bought off-the-shelf from car audio manufacturers.

This was especially true when it came to bass. I thought all the Rockford Fosgate and Pyle woofers I used 4 ohm or 8ohm were too punchy, and one-notey. That home woofer on the other hand was more natural.

I think car speakers would be tougher for an amp to control because of their 4ohm rating. They would draw more current from the amps and their damping factors would be half that of an 8ohm dirver. But in small space like a car, that may not matter as much.

Most mobile speakers target specific size and envirmental issues as in size,depth,flush fit,nominal 4ohm impeadence.
when you go to seperates the tweeters are ussually permanently grilled,neodymium magnets,and ferrofluid are most common.And to top it off most all designs expect use in free-air application.Also many off the better car tweeters tend to be focus dispersion so as not to splash highs off many unfriendly vehicle interiors as well as an increase in on axis sensitivity.Material choice is a comprimise for in car sunlight and moistures relentless
assualts.Pl++++++us!Most of the time thiele/small parameters from mobile manufacturers if available,can't be trusted.So what size cabinet vented/reflex or sealed acoustic suspension would you set out to build.
I have heard few rigs made for home from mobile sound gear
which yeilded loud and clean,yet always missed 3 dimensional
accurate sonic picture.IMHO

Gunbei: Most car stereo woofers have a high Qms, which results in a big impedance peak at resonance. This is what causes the bloated, indistinct bass that you hear from the "boom / tizz" vehicles. Lower impedances aren't a problem for a good amp, but as you mentioned, damping factor is reduced.

As a side note, damping factor is NOT the ability of the amplifier to control or load into the driver so much as it is the ratio of how much potential there is for the reflected EMF from the driver to modulate / distort the output of the amplifier. This is a very commonly misunderstood spec with even EE's, designers and manufacturers not knowing how to interpret it or what it really means.

The higher the damping factor, the less susceptable the amp is to being affected by the reactance of the speaker. The ability of the amp to efficiently transfer power into the driver / speaker system ( including cabling ) is what will determine how much "control" the amp has. Unfortunately, there is no spec for this that i'm aware of.

Take a look at this link pertaining to impedances, reactance, loading characteristics and power transfer in the AA Speaker Asylum archives. Pay special attention to the exchanges between myself and that of Dan Wiggins of Adire Audio and to a lesser extent the few responses between myself and Bobby Palkovic of Merlin. One of these two guys is a LOT smarter / more experienced than the other, but i'll leave that up to you to figure out which one it is after reading the exchanges there. While punching in T/S parameters into a computer program and then interpreting the data can provide a lot of useful information, it does not make one a knowledgable speaker designer. Sean
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Thanks for the info Sean! Have a good one.