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My new LaScala crossovers.


Danieln

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Finally, after a year with my 1988 LaScala, I replaced the AL type crossovers with a constant impedance set.

I took good care to simulate and then measure the results and i am now an happy camper :-)

 

I decided that a fix L Pad will be my preferred way to attenuate the mid range.

The original attenuation was 6 DB, but in order to make them more lively, I opted for a 4 DB pad.

 

What are your preferred attenuation?

 

Dan

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Claude, here it is, nothing very exotic except for the lack of the autoformers :-)

This is a slightly modified ALK universal. I measured the low crossover at 430 and the high at 5700 Hz,

Considering the mid driver fall as a rock at 6000, crossing a bit lower is a plus imho.

 

What is your preference for the mid attenuation in term of DBs?

 

Cross5.jpg

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Thanks for the answers,

yes I was referring to  -4 DB, and it is quite a bit more lively than -6DB.

The more I listen to it, the more I prefer -4.

Oh i see Deang, you lined-up the center of the cores. i thought that been 90 degrees apart was sufficient at these low frequencies.

 

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Check your low pass on the woofer.  The horn loading of the woofer essentially doubles the woofer impedance.  That's why Klipsch used a 2.5 mH woofer inductor.  La Scala's bass horn can comfortably go well above 400 Hz. 

 

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My spice simulation models the woofer as a 6.2 Ohms in series with a 1mH voice coil inductance. Adding my 1.25mH (Essentially two 2.5mH in parallel taken from the AL type crossover) brings the total to 2.25mH for my simulation. The resulting crossover is simulated at 417 Hz. Now, when I look at the actual electrical response of the crossover, I measure 430 Hz which matches quite well the simulation. Increasing the inductance lowers the crossover point in fact. Which crossover frequency is optimum from your point of vue?

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