DIY biamp 6-24 crossover

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Hi Ian. It is a real issue with many speakers to varying degrees. Its displayed in the acoustic in room measurements and confirmed by audibility, also by simulation. A crossover, active or passive will need control over Baffle diffraction loss.
6-24 crossover without BSC will not be enough with all speaker systems, bass level will be attenuated relative to mids/highs with many loudspeakers placed a distance from the wall??
 

6L6

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Of course baffle step is real, what Ian is getting at is if you actually need it in every application, to which the answer is of course, no.

That said, remember that there is a kind of baffle step correction that can be applied merely by the volume pots on the crossover, you can make up some of the loss by having the crossover output higher in the bass section. Is this frequency dependent targeted to the specific BSC required in your application? No, but it will do more than you'd expect.
 
If you look at Douglas Self's Active Crossover Design book baffle step compensation schematic is illustrated.
A three or four way system with a 12 or 15 inch woofer at the bottom of the baffle does not require a baffle step compensation.

Typically a 2 way tall tower with a narrow baffle under 30cm with the 6.5 inch mid bass will require baffle step compensation. Some designers add a second or 3rd woofer to offset the effect with staggered 1st order low pass crossover points.
 
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Hi everyone. I have a few questions:

1) is there a procedure to generate the component values to achieve 3rd order Butterworth filters? (having the freedom to use non-textbook filters is really good, but I would like to replicate a digital filter that is using it and compare both)

2) What is the max input voltage from the preamp if one skips the pot at input?

3) if not using the input pot at all, could the buffer be skipped w/o penalty? I have a TVC at the output of my preamp, it's output impedance varies with attenuation, but should remain bellow 1Kohm.

4) is the output level voltage on the passband of each branch of the filters the same as the input voltage if the input pot is not used?


S.
 
I have some questions about this flexible crossover.
I would like to use this crossover for test purpose on 1 3-way speaker. (mono)

Am I right to say that 1 board is sufficient to build a mono 3-way filter?
For woofer I need a low pass and for tweeter a high pass filter. But how can I build the low-high pass for the mid driver?

How can I deal with baffle step, notch filters, attenuation of mid and tweeter, etc...?
 
A few moments later...

C=50
200Hz XO

I guess I am ready to build it.

But. When hornloading Linkwitz-Riley filters are not always preferred. I better go with Butterworth filters, but how do I change to that?
 

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