8 ohm to 16 ohm driver change

TNT

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Joined 2003
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If one driver really is 8 ohm at the frequency of x-over and the other really is 16 ohm at double the frequency, and the impedance traces looks otherwise similar - the effect will be double the x-over frequency. So e.g. 2kHz -> 4kHz etc...

In your case you need either an 2,5 uF cap or two 5's in series for 2,5uF... to retain the same XO as with the 5uF cap.

Try this :

https://www.v-cap.com/speaker-crossover-calculator.php

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TNT

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Joined 2003
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Thanks. Whatever your xover might be at, halving the uF is a safe bet anyways. I would try that and if things sounds off, do an investigation.

Why change impedance version btw? :)

Can you point to the actual driver model?

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Thanks. Whatever your xover might be at, halving the uF is a safe bet anyways. I would try that and if things sounds off, do an investigation.

Why change impedance version btw? :)

Can you point to the actual driver model?

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Altec 802 8g drivers, I bought a pair with out diaphragms and Radian only has 16 ohms currently.
Have been using 299 8a 8 ohm drivers.
Trying a different driver / horn combo.
 
Higher impedance will pass more, filter less, regardless high-pass or low-pass. So parallel the 5uF with another for ~10uF.

Simplified formula 1st order filters:
HPF hz=(160khz/ohm)/uF
LPF hz=(160hz*ohm)/mH

(2nd order filters: in above, calculate uF, mH for XO frequency f=5khz/sqrt(uF*mH); then respectively multiply/divide uF, mH by the same 1<q<2 to get different curves Linkwitz-Riley, Butterworth etc.)
 
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Hmm, don't have the 299, but the many decades long 288 series is no different, only loading a PWT at rated resistance, ditto the 1" 800-900 series, though in retrospect all were measured on expo horns, so guessing they wouldn't rise on pure WGs or at least not enough to matter. Never bothered to measure my 800 series DIY parabolic WGs and used textbook 1st order with no obvious sonic issues according to even my then youthful female 'test gear'. ;)
 
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