Celestion Ditton 66 4 ohm or 8 ohm tweeter

[PK Vintage]

Hello.
Can someone explain to me what happens if I use a 4 ohm tweeter inplace of an 8ohm tweeter or an 8ohm in place of a 4ohm. Do I neet to make an adjustment to the crossover. A resistor? Or does it really matter?

Example: Celestion Hf2000 diaphrams come in 4 ohm and 8 ohm. The mid and woofer in my Ditton 66 are both 8 ohm but I think the tweeter came stock as 4 ohm but not 100% sure.

I am restoring a set of Ditton 66 that have replacement tweeters. I have 2 open circuit Hf2000's that need diaphrams. I dont know if I should buy 4 or 8 ohm diaphrams. I want to put these back in to return the speakers to stock form.

Thanks for any help.

 

[swechsler]

It's probably an 8Ω tweeter, and yes, it does make a difference. The crossover is designed for a specific impedance and using the wrong impedance will change the crossover frequency.

However, I wouldn't guess. If nobody else has this info, the first thing I'd do is contact Celestion and see if they can help you out. While in theory you could change the impedance of the driver by putting a resistor in series (to raise it) or in parallel (to lower it), either way it will affect the output, so it would no longer be at the same level as the other drivers, and it's not the correct way to do it.

If Celestion can't help you, you could plug the component values from your speaker into a crossover calculator and see what the crossover frequencies are for a 4Ω and 8Ω driver, then match that up with the original specs.