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#1
Posted to rec.audio.car
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adjustable OHM ?
I was looking for a pair of 8 ohm tweeters and stumble onto this.
Just not sure if there is such a thing such 4-8ohm(adjustable?). need everyone's comments. http://cgi.ebay.com/5-TITANIUM-HORN-...QQcmdZViewItem |
#2
Posted to rec.audio.car
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adjustable OHM ?
speakers can be made with more than one voice coil, each having their own impedence. the user can then choose to use one or both, each configuration giving a different set of properties for the speaker. this one I don't know, it says "2.8" High temp kapton voice coil" which would lead me to believe there is only one voice coil, which cannot be interchangeable between 4 and 8 ohms itself. what i think is funny is that right on the back plate is stamped "800 watts output power," as if the speaker itself sends power somewhere instead of receiving it. I'd stay far away from it. -- KU40 |
#3
Posted to rec.audio.car
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adjustable OHM ?
this one I don't know, it says "2.8" High temp kapton voice coil" which
would lead me to believe there is only one voice coil, which cannot be interchangeable between 4 and 8 ohms itself. I agree. Clearly there is one 2.8" voice coil. What I think they are referring to is what type of amp it will work with, wich is silly because the amp does not determine resistance in ohms (obviously), the speaker (or load) does. But as often the case on Ebay, the seller is being fast and loose with terminology in an effort to sell the product. He is trying to imply that this tweeter will work for both home applications (where speakers are typically rated at 8 ohms) and car applications (where speakers are typically 4 ohms). What the REAL resistance in ohms of these tweeters are I can't say. But it is DEFINATELY NOT BOTH 4 AND 8! It is one or the other. I would ask the seller. MOSFET |
#4
Posted to rec.audio.car
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adjustable OHM ?
MOSFET wrote:
this one I don't know, it says "2.8" High temp kapton voice coil" which would lead me to believe there is only one voice coil, which cannot be interchangeable between 4 and 8 ohms itself. I agree. Clearly there is one 2.8" voice coil. What I think they are referring to is what type of amp it will work with, wich is silly because the amp does not determine resistance in ohms (obviously), the speaker (or load) does. But as often the case on Ebay, the seller is being fast and loose with terminology in an effort to sell the product. He is trying to imply that this tweeter will work for both home applications (where speakers are typically rated at 8 ohms) and car applications (where speakers are typically 4 ohms). What the REAL resistance in ohms of these tweeters are I can't say. But it is DEFINATELY NOT BOTH 4 AND 8! It is one or the other. I would ask the seller. I would tend to suspect the same, that the impedance listing simply means it will "work" with amps designated for 4-8 ohm outputs. Actually, the ebay listing's specs very closely (but don't exactly) mirror others I found on the 'net. Example: From http://www.westcoastmall.net/shop/pr...oducts_id=2762 * 4" Heavy Duty Titanium Super Tweeter (odd, the ebay add says 5") * Die Cast Aluminum Frame * Diamond Chrome Cutting Finish * 2.8" High Temperature Kapton Voice Coil * 130 Oz Magnet Structure * 400 Watts RMS / 800 Watts Peak Power * 4-8 Ohms Impedance * Ferra Fluid Enhanced Voice Coil (FERRA? Correctly, it's "ferrofluid".) * Sensitivity: 105dB * Frequency Response 2K-25KHz * Mylar Crossover Pack in Gift Box * Single Pack The specs appear to be pretty much cut'n'pasted from Audiopipe's website - they don't list the 6650 specifically, but they do list three other "titanium" tweeters with nearly identical specs (including "4-8 OHMS Impedence"). http://www.audiopipe.co.uk/Productli...m%2 0Tweeters Interestingly, their subs don't like frequency "ranges", and their "other tweeters" all list "Impedance: 4 Ohms (Can be used with 8 & 16 Ohms systems)". I think I'll drop them an email... |
#5
Posted to rec.audio.car
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adjustable OHM ?
MOSFET wrote:
What the REAL resistance in ohms of these tweeters are I can't say. But it is DEFINATELY NOT BOTH 4 AND 8! It is one or the other. I would ask the seller. Except it's not 'resistance', it's 'impedance'. I'm sure you know this, impedance changes at different freq's, so technically, the seller could be claiming that the impedance ranges between 4 and 8 across the freq spectrum. I doubt it tho, that'd be a weird way to word it.. I'd just call em 4ohm tweeters. From what I've seen, impedance is lowest at the low end if it's normal freq response, like around 3kHz. It rises to 3-5 times that at 20kHz, and the plot looks parabolic. Testing a tweeter for resistance, ie sticking an ohmmeter across your speaker's terminals would probably give you something close to the lowest impedance across the entire freq spectrum. |
#6
Posted to rec.audio.car
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adjustable OHM ?
thanks everyone...
i better skip this.hehehe "mfreak" wrote in message ups.com... MOSFET wrote: What the REAL resistance in ohms of these tweeters are I can't say. But it is DEFINATELY NOT BOTH 4 AND 8! It is one or the other. I would ask the seller. Except it's not 'resistance', it's 'impedance'. I'm sure you know this, impedance changes at different freq's, so technically, the seller could be claiming that the impedance ranges between 4 and 8 across the freq spectrum. I doubt it tho, that'd be a weird way to word it.. I'd just call em 4ohm tweeters. From what I've seen, impedance is lowest at the low end if it's normal freq response, like around 3kHz. It rises to 3-5 times that at 20kHz, and the plot looks parabolic. Testing a tweeter for resistance, ie sticking an ohmmeter across your speaker's terminals would probably give you something close to the lowest impedance across the entire freq spectrum. |
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