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Zilch crossover question

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The crossover seen in the right-hand side of your photo is electrically the same as the one on the left.

The difference is ( the one on the right ) is DC biased ( also called; charge-coupling ) .
FYI; DC biasing uses twice as many caps, each of which is twice the uF value ( when compared to the originals ).

You'll need to Google about the subject and then decide for yourself if the investment is worth it .

If Zilch were alive today, I'm confident he would dissuade people from using the referenced network .

By the time Zilch died in 2011, he knew so much more than what a lot of his older thread-efforts display ( ie; it was over the course of the year 2010, that he learned how to design custom networks ).

:)
 
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Hmmm. I already bought the tweeters so I'll have to figure something out.
Thanks for the info Earl. I doubt I'm going to design my own crossover, but I guess I'll look into it. I'm thinking it requires equipment I don't have.
Any good beginner links?
 
In case you are using the JBL le10a along with a new Morel CAT 378 here's one possible network for you .

JBL_L77_LE10a_CAT378_3x2_network-study.png


The network prediction was done in XSim.

- I used Zilch's le10a frequency responses ( FPtraced & turned into an .frd files ) along with my own .zma files created by "WooferTester2" from my own le10 woofers ( one can see that it needs a new surround ).

- The Morel CAT 378 ( .frd + .zma ) files were created from their product sheet ( using FPGraph Tracer . )

- As mentioned within the picture / the difference in distances between the "Acoustic Centers" ( of the 2 drivers ) was guesstimated at around 2.5" .

:)
 
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LE10 and Morel CAT 378 are what I have, but my woofers are refoamed despite my best efforts. Lansaloy sucks.

I appreciate the effort Earl. That does look smoother than Zilch's post, but yours doesn't go as low. Is that a program limitation of XSim, or just your freq limit?
How many watts are the resistors?
Looks like I've got some reading to do.
 
XSim can start the frequency display at 10hz ( but I chose not to since I was using Zilchs frequency files and he always maintained to not trust much of what he displayed below @ 500hz ).

I would use 10 watt resistors to be safe ( for home listening levels ).

:)
 
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BTW, the crossover prediction I posted yesterday is for the le10a ( not the le10 or the le10H or the le111a ) . If you use it, there's bound to be some errors in how things fit together in the crossover area ( as well as maybe too much midrange from 400-1000hz ) .

So you know, your le10 woofers are really ancient examples of JBL's 10" family.

Your woofs are missing the white or black aquaplas coating found covering either the front or back of the cone ( this treatment was ubiquitous on all the later examples ).

Your woofs might be more efficient due to lacking this coating and if it has the same voice-coil ( OTOH, if it's an extra heavy cone with a different VC, then all bets are off ) .

What's the dcr of the voice coil for either le10 ?
- ( le10a's are quite low > around 4.5 ohms , le10H's are a bit higher ) really making them a 6 ohm woofer .

If you decide to use my crossover design ( & to cover your bases if the woofer is really different ) you might want to use a variable Lpad on the tweeter circuit ( at first ) in place of the R1 & R2 .

:)

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teal'c said:
The woofers read 4.8 ohms.
Click to expand...

Good, that means the voice-coil on your version of the le10a is most likely the same as that found on the le10a .

That helps support the network prediction that I made ( OTOH, the difference in cone types still detracts from the prediction ).

:)
 
Does anyone know the name of the through-hole component clips that Zilch used in the red crossover board on the right in the first post? I’d like to continue building with these clips but I can’t seem to find a source or name to search for online. ¯\_(ツ)_/¯
 
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