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tweeter
11-23-2009, 09:09 AM
What is the correct impedance of the drivers?
For example, I can see in the market 066 tweeters with impedance from 3.9 to 4.6 ohms.

Mr. Widget
11-23-2009, 09:24 AM
What is the correct impedance of the drivers?
For example, I can see in the market 066 tweeters with impedance from 3.9 to 4.6 ohms.You are confusing DC resistance with AC impedance.

I don't know the correct range of DCR for that tweeter, but 3.9 to 4.6 seems likely to be in the acceptable range. I imagine someone on this board has the factory specs and they might chime in. That said, having a used tweeter with the correct DCR does not guarantee much.


Widget

Robh3606
11-23-2009, 09:25 AM
Impedance is frequency dependent. It is the DCR value plus the added reactive resistance from the coil. What you see in the E-Bay adds are the DCR only. As long as it's within "nominal values" it's fine. The Impedance value be it 8 or what have you is just a general approximation. 4/8/16 being the common ratings.

Rob:)

rdgrimes
11-23-2009, 09:33 AM
The spec for the 066 is 3.5-4.4 DC resistance.

These values are all listed in the spec sheets for each speaker model in the "links" section of the forum.

Mr. Widget
11-23-2009, 09:36 AM
The spec for the 066 is 3.5-4.4 DC resistance.

These values are all listed in the spec sheets for each speaker model in the "links" section of the forum.Thanks.


Widget

Allanvh5150
11-23-2009, 10:35 AM
Impedance is frequency dependent. It is the DCR value plus the added reactive resistance from the coil. What you see in the E-Bay adds are the DCR only. As long as it's within "nominal values" it's fine. The Impedance value be it 8 or what have you is just a general approximation. 4/8/16 being the common ratings.

Rob:)

But dont forget, a spaeker can stll have perfect DCR but have a shifted magnet and hence a locked voice coil.

Allan.

rdgrimes
11-23-2009, 10:47 AM
Yup. I have tweets (and mids too) that have perfect DCR, and free voice coils that still don't work, or work badly. But it's a good start to know the DCR is right.