Jim Cornell Posted October 13, 2002 Share Posted October 13, 2002 Today i pulled both K-33-Es out vacumed out the bass bins, cleaned up the woofers! Using an OHM meter i got 3.3Ohms on 1 woofer 3.5 Ohms on the other, i hope their both ok, they look like new, no wrinkles tears nothing! I cleaned up my Squawker, taking the K-55-Vs off, they looked fine! I cleaned up the crossovers, they look as new, very nice, also i cleaned all the dust and dirt off the back vents, and the cabinet, very nice! I also replaced the seal with a nice weather stripping, so down the road i can take the doors off again! I was looking at the AA crossover, if someone put a clock on it, i think it would pass for a bomb LOL! You should of seen the look on my 8 year olds face, i told her NO daddy isnt going to blow something up, its for the speaker LOL! Regards Jim Quote Link to comment Share on other sites More sharing options...
lynnm Posted October 13, 2002 Share Posted October 13, 2002 Hello Dere Jim! I wouldn't get too excited about a difference of .2 ohms DC resistance between the woofers' voice coils. Bear in mind that you are measuring the DC resistance as opposed to AC resistance,(aka impedance), and further if you do the math there is a very small difference here 3.5/3.3 results in an approximately 6 % difference in DC resistance. If one were dealing in the megohm range then a difference of 6% might be significant but that is not the case here. I do not pretend to fully understand the difference between DC resistance and Impedance beyond the fact that a device/medium will present a different momentarily measurable resistance to a current dependent upon whether that voltage is a DC current - at 0 cps (ie steady state -Postive and negative polarity remains constant) or an AC source with a constantly alternating polarity ). The specific why's and wherefores are best left to the experts. There will be a time delay during each cycle between the time a given + point on a sine wave becomes - (and vice versa) and further that time delay will be longer at low frequencies and shorter at higher frequencies and further the dominant frequency will change very frequently within any given time frame. I can however state that DC resistance is not a reliable predictor of speaker performance because not only is one dealing with electrical resistance/impedance but also the effect of the cabinet design upon the acoustic output of any given driver. I doubt that anyone builds speaker cabinets based upon the DC resistance of any given driver because few if any manufacturers are capable of building drivers that are absolutely identical in electrical character, although any competent maker should be capable of producing drivers that when measured against a standard will be effectively identical. If anything enclosure designers would be more likely to take the impedance range of a given driver into account as merely one of the many variables to be addressed when designing a cabinet and make allowance within the design to accomodate the inevitable minor differences likely to be encountered from driver to driver. In addition unless you measured those drivers totally independently of the Xcrosser networks, (ie measured their DC resistance w/o any connection to the networks then the difference you saw might well be due to components external to the drivers themselves). Bottom line If they sound good - ignore the minor difference you have dredged up to torment yourself with! Quote Link to comment Share on other sites More sharing options...
Jim Cornell Posted October 13, 2002 Author Share Posted October 13, 2002 Thank you Lynn I just tested it for the hell of it, everything is working and sounding fine, i just wanted to clean up 22 years of dirt and dust! Regards Jim Quote Link to comment Share on other sites More sharing options...
djk Posted October 13, 2002 Share Posted October 13, 2002 The difference in impedance will cause the 3R3 woofer to draw 0.25dB more power than the 3R5 one. ((P1/P2)log^10)*10=dB When comparing voltages it is *20=dB Quote Link to comment Share on other sites More sharing options...
Chris Robinson Posted October 14, 2002 Share Posted October 14, 2002 Ah, the beauty of false precision. Certainly we err on the side of jocularity, nay? Quote Link to comment Share on other sites More sharing options...
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