Interesting post Adam. You make some very good points. Some of my own comments...
<font face="Verdana, Arial" size="2">Originally posted by adam1991:
Subwoofer is a marketing term that came about over the last several years, and is mis-used every time a marketing geek says it. Subwoofers need 15" drivers or better and go 20-100Hz max, and they need A LOT of power to move that much air.
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Use of the term "subwoofer" seems to be a minor semantic issue; I use the term to describe a stand alone low frequency module, separate from full range speakers. Usually bandwidth is limited to the 20Hz-150Hz range. Perhaps many misuse the term, but I think most people understand it in a concept very similar to my usage, correct or not...
I very much disagree with the notion that a 15" driver is needed to get low bass response (down to 20 Hz). In the case of cars, the transfer function of the vehicle affects response so dramatically, even drivers as small as 6.5" OD can get very low. It's more a matter of efficiency, power handling and excursion, which translates ultimately to SPL.
In the home, there are plenty of examples of 10" and 12" subwoofers that get down to ~25Hz without a problem, and can shake the walls of an average size room at that! The NHT 1259 is a wonderful driver that, with a properly sized/tuned enclosure, goes that low and provides audiophile like sound. Velodyne's servo subs also have no problem getting that low in 10" and 12" sizes too. (but can't obviouly play as loud as their 15")
Then the converse of this is the 15" guitar amp speaker (high Q, light cone, textile surround) that can barely play down to 65Hz. Size really isn't the main design parameter, unless you are talking SPL (and somewhat) efficiency.
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It's too hard to explain the difference between good (proper) sound reproduction and boom-car sub-bass when your audience is the mass market.
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Sound quality is VERY subjective, and not everyone likes the same thing. Ideally, good sound reproduction is exactly that: reproducing the original recording in a lifelike manner. However, with digial recording technology, EQing in the studio, after recording mixing (even with classical symphony recordings!), this gets very confusing. Also, different people like different sounds, according to their musical preferences, etc..
The typical boomer tends to have a 12dB resonance right around 60 Hz, as this is where most cars tend to amplify the best. That's the "one-note" sound of the boom car. Seems to me that only bigtime rap fans like this type of setup though...
What makes car audio difficult for bass response is the preponderance of sub 100Hz noise in the vehicle. In order to hear the low frequencies reasonably well, the car must be tuned to have a rising response on the low end. This, and sound proofing, are the only way to hear low frequencies reasonably well.
My subwoofer system (I definitely call it a sub, f3 in car ~23Hz) uses a separate remote volume control (many companies offer this for their amps or amplified systems) so that I can tune in the amount of bass based on music, driving speed (ambient noise level) etc...
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All I want in my Ody is decent sound, and that includes actual bass. The Kelton box goes up to 400Hz; that's not a subwoofer, that's just a bass module.
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I too am in the search of decent sound in the Ody too...(my wife thinks my definition of decent means perfection
hee,hee)
I can't believe the Kelton plays up to 400Hz! (never seen or heard one myself) That is just ridiculous. If it plays that high, there will be ALOT of localization of that speaker, and sound stage, imaging, etc should be severely compromised... How did you find out about its x-over f?
(edited just now...) Oh, but just occurred to me that the Kelton unit has adjustable x-over f. So if 400Hz is the top end, how low can you adjust the f, anyone know?
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Now, if the system is crossed over correctly such that we can prevent the 6.5ers from even TRYING to reproduce anything below 350Hz, that would be great. I'm not holding my breath, though.
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Crossing over the front speakers with passive crossovers is very easy. Just a simple capacitor in series for 6dB/oct., a cap in series and inductor in parallel for 12dB/oct. You can get a steeper slope, but phase response tends to suffer a bit beyond those. I'd recommend crossing over the main speakers at ~85-100Hz, to save the factory head unit some dynamic headroom on the highs, then setting the sub crossover similarly. A slight bit of overlap on the frequencies usually ensures flatter, more natural response.
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But look at us--we spend $120 total swapping out Honda's speakers, and improve the sound 300%. That's plain wrong.
That's the biggest wart Honda has. Fortunately, it's fixable. But it's still annoying that such a great company building such great and quality cars can dump that crap on its customers.</font>
Very right indeed, we all think this sound system is terrible. In my perspective though, I never keep factory anyway, so I'm buying the car more for it's other capabilities anyway, and I must say I've never been more pleased with a car purchase as I have this vehicle!
Just my 2 cents.
-SJ
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DEP '01 EX no-navi
[This message has been edited by shinjohn (edited 09-04-2001).]
